Report of the ICES Advisory Committee, 2009

ICES ADVICE 2009 AVIS DU CIEM Books 1-11 Report of the ICES Advisory Committee, 2009 Book 6 North Sea International Council for the Exploration of the Sea Conseil International pour l Exploration de la Mer

H.C. Andersens Boulevard 44-46 DK-1553 Copenhagen V Denmark Telephone (+45) 33 38 67 00 Telefax (+45) 33 93 42 15 www.ices.dk info@ices.dk Report of the ICES Advisory Committee 2009. Books 1-11 December 2009 Recommended format for purposes of citation: ICES. 2009. Report of the ICES Advisory Committee 2009. ICES Advice, 2009. Book 6, 236 pp. For permission to reproduce material from this publication, please apply to the General Secretary. ISBN 978-87-7482-072-7

BOOK 6 Section Page 6 NORTH SEA... 1 6.1 Ecosystem Overview... 1 6.2 The human impacts on the ecosystem... 1 6.2.1 Fishery effects on benthos and fish communities... 1 6.3 Assessments and advice... 1 6.3.1 Assessments and advice regarding protection of biota and habitats... 1 6.3.2 Assessment and advice regarding fisheries... 1 6.3.3 Special requests... 8 6.3.3.1 EC and Norway request on in-year management advice for sandeel in the North Sea... 8 6.4 Stock summaries... 12 6.4.1 Cod in Division IIIa East (Kattegat)... 12 6.4.2 Cod in Subarea IV (North Sea), Divison VIId (Eastern Channel) and IIIa West (Skagerrak)... 20 6.4.3 Haddock in Subarea IV (North Sea) and Division IIIa West (Skagerrak)... 43 6.4.4 Whiting in Division IIIa (Skagerrak Kattegat)... 55 6.4.5 Whiting in Subarea IV (North Sea) and Division VIId (Eastern Channel)... 57 6.4.6 Plaice in Division IIIa (Skagerrak Kattegat)... 69 6.4.7 Plaice in Subarea IV (North Sea)... 72 6.4.8 Plaice in Division VIId (Eastern Channel)... 85 6.4.9 Sole in Division IIIa (Skagerrak Kattegat)... 90 6.4.10 Sole in Subarea IV (North Sea)... 99 6.4.11 Sole in Division VIId (Eastern Channel)... 110 6.4.12 Saithe in Subarea IV (North Sea) Division IIIa (Skagerrak) and Subarea VI (West of Scotland and Rockall)... 119 6.4.13 Nephrops in Division IIIa (Skagerrak Kattegat)... 130 6.4.14 Nephrops in Division IV (North Sea)... 131 6.4.14.1 Nephrops in Moray Firth (FU 9)... 139 6.4.14.2 Nephrops in Noup (FU 10)... 140 6.4.14.3 Nephrops in Fladen Ground (FU 7)... 146 6.4.14.4 Nephrops in Norwegian Deeps (FU 32)... 152 6.4.14.5 Nephrops in Farn Deeps (FU 6)... 159 6.4.14.6 Nephrops in Firth of Forth (FU 8)... 165 6.4.14.7 Nephrops in Botney Gut Silver Pit (FU 5)... 166 6.4.14.8 Nephrops off Horn s Reef (FU 33)... 167 6.4.15 Herring in Division IIIa and Subdivisions 22-24 (Western Baltic spring spawners)... 168 6.4.16 Herring in Subarea IV and Divisions IIIa and VIId (North Sea autumn spawners)... 178 6.4.17 Sprat in Division IIIa (Skagerrak Kattegat)... 194 6.4.18 Sprat in the Subarea IV (North Sea)... 195 6.4.19 Horse mackerel (Trachurus trachurus) in Divisions IIIa, IVb,c and VIId (North Sea stock)... 200 6.4.20 Norway pout in Subarea IV (North Sea) and Division IIIa (Skagerrak Kattegat)... 204 6.4.21 Sandeel in Division IIIa (Skagerrak Kattegat)... 212 6.4.22 Sandeel in Subarea IV excluding the Shetland area... 214 6.4.23 Sandeel in Division IVa North of 59 N and West of 0 E (Shetland area)... 226 6.4.24 Northern shrimp (Pandalus borealis) in Division IVa (Fladen Ground)... 227 6.4.25 Northern shrimp (Pandalus borealis) in Divisions IIIa West and IVa East (Skagerrak and Norwegian Deeps)... 229 6.4.26 Demersal elasmobranchs in the North Sea, Skagerrak, and Eastern Channel... 236 ICES Advice 2009, Book 6 i

6 NORTH SEA 6.1 Ecosystem overview This Section has not been updated in 2009. The most recent ecosystem overview is available in ICES Advisory Report 2008, Section 6.1. This overview can also be found on the ICES website: http://www.ices.dk/committe/acom/comwork/report/2008/2008/6.1-6.2%20north%20sea%20ecosystem%20overview.pdf. 6.2 Human impacts on the ecosystem 6.2.1 Fishery effects on benthos and fish communities This Section has not been updated in 2009. The most recent description on Fishery effects on benthos and fish communities is available in ICES Advisory Report 2008, Section 6.2. This description can also be found on the ICES website: http://www.ices.dk/committe/acom/comwork/report/2008/2008/6.1-6.2%20north%20sea%20ecosystem%20overview.pdf. 6.3 Assessments and Advice 6.3.1 Assessment and advice regarding protection of biota and habitats In 2009, ICES has not provided advice regarding protection of biota and habitats for this area. 6.3.2 Assessments and Advice regarding fisheries In 2007 the timing of the advisory process for the North Sea was changed at the request of ICES clients. This means that the fisheries advice is delivered in the first half of the year instead of in October. To evaluate whether new information that becomes available after the advice is released would form a basis to update the advice ICES has developed a generic approach (AGCREFA, 2008a). The approach is based on a statistical evaluation of the importance of that information (e.g. new survey information available in August/September). The state and the limits to exploitation of the individual stocks are presented in the stock sections. The state of the North Sea stocks and single-stock exploitation boundaries are summarized in table 6.3.2.1 below. For the stocks of elasmobranchs (rays, skates, sharks), Nephrops in Division IIIa, and deep-water species, ICES provides advice every second year. The 2008 advice for these stocks can be found in table 6.3.2.2 and 6.3.2.3 and is valid for both 2009 and 2010. 6.3.2.1 Mixed fisheries and fisheries interactions This Section has not been updated in 2009. The most recent description on Mixed fisheries and fisheries interactions is available in ICES Advisory Report 2008, Section 6.3. This description can also be found on the ICES website:. http://www.ices.dk/committe/acom/comwork/report/2008/2008/6.3%20north%20sea%20fisheries%20advice.pdf Sources of information ICES. 2008a. Report of the Ad hoc Group on Criteria for Reopening Fisheries Advice (AGCREFA), 20 22 August 2008, Copenhagen, Denmark. ICES CM 2008/ACOM:60. ICES. 2008b.ICES Advisory Report 2008, Book 6. ICES Advice 2009, Book 6 1

2 ICES Advice 2009, Book 6 Single-stock exploitation boundaries and critical stocks Table 6.3.2.1 Single stock advice for North Sea stocks, summary of state of stocks and single-stock exploitation boundaries. The state and the limits to exploitation of the individual stocks are presented in the stock sections. Stocks State of the stock ICES considerations in relation to single-stock exploitation boundaries Upper limit Cod in Kattegat Cod in the North Sea, Eastern Channel and Skagerrak Haddock in the North Sea and Division IIIaN Whiting in Division IIIa Whiting in the North Sea and Eastern Channel Plaice in Division IIIa Plaice in the North Sea Spawning biomass in relation to precautionary limits Reduced reproductive capacity Reduced reproductive capacity. Full reproductive capacity. Fishing mortality in relation to precautionnary limits Fishing mortality in relation to high longterm yield Fishing mortality in relation to agreed management target In relation to agreed management plan Unknown Unknown Unknown F reduction of 25% cannot be reliably estimated, thus a 25% TAC reduction: 379 t Increased risk Harvested sustainably Overfished Appropriate Above target. Below target Assuming efficient enforcement (F reduction and effort control), the management plan implies landings of less than 40 300 t Landings of 38 000 t (15% TAC reduction, including industrial bycatch). in relation to precautionary limits No catches of this stock No catches of this stock, stock cannot rebuild to B pa even with zero catches Human consumption landings < 76 000 t bring the stock down to B pa. in relation to high longterm yield corresponding to single-stock exploitation boundary. Tonnes or effort in 2010 Zero catches. F is above F HCR = 0.4. < 40 300 t, assuming efficient enforcement F is below F HCR = 0.3. 38 000 t, including industrial bycatch. No change in the perception of the stock Same advice as last year < 1050 t, recent average landings. Undefined Undefined Overfished Significant reduction Significant of TAC to remedy reduction of SSB decline in SSB (-64% to stabilize SSB < 6 800 HC catch) No change in the perception of the stock Same advice as last year < 9400 t Full reproductive capacity. Harvested sustainably Overfished Below target A maximum reduction of 15% in the TAC corresponds to landings of 63 825 t. Catches < 138 100 t corresponding to F pa. F is above F max. 2 ICES Advice 2009, Book 6 63 800 t

ICES Advice 2009, Book 6 3 Stocks State of the stock ICES considerations in relation to single-stock exploitation boundaries Upper limit Plaice in the Eastern Channel Sole in Division IIIa Sole in the North Sea Sole Eastern Channel Saithe in the North Sea, Division IIIa and Subarea VI Herring in IIIa and Subdivisions 22-24 (spring spawners) Herring in the North Sea, VIId and IIIa (autumn spawners) Sprat in Division IIIa Spawning biomass in relation to precautionary limits Fishing mortality in relation to precautionnary limits Fishing mortality in relation to high longterm yield Fishing mortality in relation to agreed management target In relation to agreed management plan ICES Advice 2009, Book 6 3 in relation to precautionary limits Unknown Unknown Unknown Unknown Recent average landings < 3 500 t Full reproductive capacity. Full reproductive capacity. Full reproductive capacity. Full reproductive capacity. Harvested sustainably Harvested sustainably Increased risk Harvested sustainably Appropriate Appropriate Overfished Above target No agreed target. A 10% reduction in fishing mortality would lead to landings of 14 100 t. Appropriate Appropriate A maximum reduction of 15% in the TAC corresponds to landings of 118 000 t Catches < 620 t corresponding to F pa. Catches < 17 800 t corresponding to F pa. Catches < 3 190 t corresponding to F pa. Landings < 132 000 t to retain the stock above B pa in relation to high longterm yield F is above the range of candidate reference points. F is above the range of candidate reference points. F is close to the candidate reference point. Undefined Undefined Overfished Catches < 39 800 t corresponding to candidate reference point F = 0.25 Increased risk. Harvested sustainably Overfished Above target. Following the management plan catches for fleet A < 164 300 t fleet B < 10 400 t F is above candidate reference points corresponding to single-stock exploitation boundary. Tonnes or effort in 2010 < 3 500 t < 620 t < 14 100 t < 3 190 t 118 000 t < 39 800 t fleet A < 164 300 t fleet B < 10 400 t, see scenario s No change in the perception of the stock Same advice as last year Limit by restriction on juvenile herring catch.

4 ICES Advice 2009, Book 6 Stocks State of the stock ICES considerations in relation to single-stock exploitation boundaries Upper limit Sprat in the North Sea Norway pout North Sea Nephrops in Subarea IV, FU6 Nephrops in Subarea IV, FU7 Nephrops in Subarea IV, FU8 Nephrops in Subarea IV, FU9 Nephrops in Subarea IV, 'Other areas' Sandeel in Division IIIa Sandeel North Sea Sandeel in Shetland area Pandalus in the Fladen Ground Spawning biomass in relation to precautionary limits Fishing mortality in relation to precautionnary limits Fishing mortality in relation to high longterm yield Fishing mortality in relation to agreed management target In relation to agreed management plan in relation to precautionary limits Unknown Unknown Unknown No basis for numerical advice, recent catch has created no problems Full reproductive capacity. in relation to high longterm yield corresponding to single-stock exploitation boundary. Tonnes or effort in 2010 No advice Undefined Undefined Maintain SSB > Bpa. < 307 000 t. Unknown Unknown Unknown Landings < 1 210 t, Harvest rate should not exceed F 2008 Unknown Unknown Unknown Landings < 16 419 t, Harvest rate should not exceed F 0.1 Unknown Unknown Unknown Landings < 1 567 t, Harvest rate should not exceed F max Unknown Unknown Unknown Landings < 1 372 t, Harvest rate should not exceed F 2008 Unknown Unknown Unknown Recent average landings < 1 500 t, (2006-2008) Increased risk Insufficient information to evaluate stock trends. Undefined Undefined Fishery should only be allowed if monitoring shows the stock can rebuild to B pa by 2011 Insufficient information to evaluate stock trends. Insufficient information to evaluate stock trends < 1 120 t and manage on stock basis < 16 420 t and manage on stock basis < 1 570 t and manage on stock basis < 1 370 t and manage on stock basis < 1 500 t No advice. In year monitoring No advice. No advice. 4 ICES Advice 2009, Book 6

ICES Advice 2009, Book 6 5 Stocks State of the stock ICES considerations in relation to single-stock exploitation boundaries Upper limit Pandalus in the Skagerrak and Norwegian Deep Mackerel in the North Sea Horse mackerel in the North Sea Spawning biomass in relation to precautionary limits Fishing mortality in relation to precautionnary limits Fishing mortality in relation to high longterm yield Fishing mortality in relation to agreed management target In relation to agreed management plan ICES Advice 2009, Book 6 5 in relation to precautionary limits Unknown Unknown Undefined No increase in landings above 2008 level ICES advises that the existing measures to protect the North Sea spawning component remain in place. in relation to high longterm yield corresponding to single-stock exploitation boundary. Tonnes or effort in 2010 < 13 000 t Lowest practical level No change in the perception of the stock Same advice as last year. TAC < 18 000 t.

6 ICES Advice 2009 Book 6 Table 6.3.2.2 North Sea stocks with biennial advice. The advice from 2008 is valid for 2009 and 2010. The state and the limits to exploitation of individual stocks are presented in the stock sections available on ICES 2008b. Stocks State of the stock ICES considerations in relation to single-stock exploitation boundaries Upper limit Nephrops in Division IIIa (FUs 3 and 4) Nephrops in Subarea IV, FU5 Nephrops in Subarea IV, FU10 Spawning biomass in relation to precautionar y limits Fishing mortality in relation to precaution ary limits Fishing mortality in relation to high long-term yield Fishing mortality in relation to agreed manageme nt target In relation to agreed management plan in relation to precautionary limits Unknown Unknown Unknown There are no signs of decline in the stocks and therefore current levels of exploitation and effort appear to be sustainable in relation to high long-term yield corresponding to single-stock exploitation boundary. Tonnes or effort in 2010 Current effort appears to be sustainable Unknown Unknown Unknown No increase in effort. No increase in effort. Unknown Unknown Unknown No increase in effort < 240 t and no and average landings increase in effort. (2003 2005). Nephrops in Subarea IV, FU32 Unknown Unknown Unknown No increase in effort. No increase in effort. Nephrops in Subarea IV, FU33 Unknown Unknown Unknown No increase in effort. No increase in effort. Demersal elasmobranchs in the North Sea Combined * Unknown Unknown Unknown Combined catches for demersal skates and rays should be set on the basis of the recent average landings (2002 2006). Subject to the individual recording of landed species, no targeted fisheries and minimal bycatch of common skate and undulate ray and no landings of angel shark. < 3100 t Spurdog ** The stock is depleted and may be in danger of collapse. The advice for 2009 and 2010 is the same as the advice given in 2006: Targeted fisheries should not be permitted to continue, and bycatch in mixed fisheries should be reduced to the lowest possible level. The TAC should cover all areas where spurdog are caught in the northeast Atlantic and should be set at zero (...).. Zero catches, low bycatch. * See table 6.3.2.3 Demersal elasmobranchs in the North Sea by species ** Spurdog advice is presented in ICES 2008b Section 9.4.6 6 ICES Advice 2009, Book 6

ICES Advice 2009, Book 6 7 Table 6.3.2.3 Individual advice for demersal elasmobranchs in the North Sea. The advice from 2008 is valid for 2009 and 2010. Species Area State of stock Advice Common skate IVa (likely merging with VIa&IIa) Depleted No target fisheries Thornback ray IVc, VIId Stable/increasing Status quo catch IVa,b Uncertain No advice Spotted ray IVb,c Stable/increasing Status quo catch Starry ray IVa,b, IIa Stable Status quo catch Cuckoo ray IVa,b Stable Status quo catch Blonde ray IVc, VIId Uncertain No advice Undulate ray VIId, merges with VIIe Uncertain, reasons for No target fisheries concern Lesser-spotted dogfish IVa,b,c, VIId Increasing Status quo catch Smooth hound & IVa,b,c, VIId Increasing Status quo catch Starry smooth hound Angel shark IVa,b,c, VIId Extirpated No fisheries ICES Advice 2009, Book 6 7

6.3.3 Special Requests 6.3.3.1 EC and Norway request on in-year management advice for sandeel in the North Sea The European Community (EC) and Norway requested ICES to provide further advice to allow EC to apply the procedure described in COUNCIL REGULATION (EC) No 43/2009, ANNEX IID. ICES understands the method referred to in the request as the method for setting the TAC for sandeel in the North Sea as suggested by ICES in its advice on harvest control rules and long-term management strategies for sandeels (ICES Advice, 2007, 2008a) and that the TAC calculated by this method shall apply to all catches of sandeel (EC and Norway). Annex IID prescribes a Real-Time Monitoring (RTM) fishery of sandeel during weeks 14 to 18 in 2009 to estimate the abundance and mean weight of the 2008 year class. These estimates are used in the formula TAC 2009 = -287 + 3.98 * N1 * (W obs / W m ) where N1 is the real-time estimate of age group 1 sandeel in billions derived from the exploratory fishery in 2009; the TAC is expressed in 1000 tonnes; W obs is the observed mean weight of age group 1 during the exploratory fishery; and W m (3.8 g) is the long-term mean weight of an age 1 sandeel. The estimation of the year class (N1) is as previously outlined in ICES (2007) and ICES (2008a). ICES response Based on real-time monitoring data from weeks 14 to 18 in 2009, the estimated stock size estimate of age 1 sandeels in 2009 is approximately 130 billion individuals and the estimated mean weight of an age 1 sandeel in 2009 is 6.11 g. Adjusting for over-sampling along the Danish coast, these estimates become approximately 118 billion individuals and 5.86 g, respectively. Using these corrected estimates, the calculated 2009 TAC value based on the formula above is 435 000 t, higher than the agreed maximum TAC of 400 000 t. Therefore, the total 2009 TAC (for EC and Norway combined) for sandeel in the North Sea should be 400 000 tonnes as specified in the agreement. However, there are concerns about the applicability of this approach to TAC-setting which is based on the invalid assumption that there is a single stock of sandeel in the North Sea. Technical background to the ICES response This response is based on 2009 data from the Danish fishery (extracted from the Danish Fishery Directorate s database on 5 May 2009) and the Norwegian fishery (received from IMR 5 May 2009). This year the data pertain only to the main historical fishing grounds in the EU EEZ, as the sandeel fishery has been closed in the Norwegian EEZ. Total landings of 67 500 t, including 5700 t Norwegian landings, have been reported so far this year. Logbook information from 108 trips and data from 83 biological samples of sandeel landings obtained between 1 April and 4 May 2009 were used to estimate the abundance of the 2008 cohort of sandeels at age 1. International landings during April-May 2009 were concentrated in a band stretching from the Dogger Bank area to the coast of the northern Jutland. This spatial distribution of landings is similar to that observed last year and is more concentrated than in 2004, 2006 and 2007. The maps in Figure 6.3.3.1.1 indicate the spatial distribution of the sandeel harvests and samples during weeks 14 18 in 2009. Based on real-time monitoring data from weeks 14 to 18 in 2009, the estimated stock size estimate of age 1 sandeels in 2009 is approximately 130 billion individuals and the estimated mean weight of an age 1 sandeel in 2009 is 6.11 g. Landings from the area along the Danish coast (e.g. rectangle 42F7 and 43F7) were over-sampled relative to landings from other areas as the Danish coast area is fished by relatively small vessels on day-trips, resulting in a high number of trips per tonne of landings. Adjusting for this over-sampling, both the 1-group estimate of stock size and mean weight are reduced (approximately 118 billion individuals and 5.86 g, respectively); leading to a calculated value according to the agreed procedure described in COUNCIL REGULATION (EC) No 43/2009, ANNEX IID of 435 000 t, slightly greater than the agreed maximum TAC of 400 000 t. The standardized catch per unit of effort (cpue) in 2009 was relatively stable over the monitoring period varying from 47 t day 1 in week 14 to 52 t day 1 in week 18. Statistics for age 1 sandeel in 2009 are presented below. Values by weeks are based on cumulative data, including the given week. 8 ICES Advice 2009, Book 6

Week number Dates (day/month day/month) Cumulative Mean weight (g) Cumulative cpue (number caught per standardized day absent) Cumulative Estimated age 1 sandeel numbers in the sea (billions) 14-15 01/04 15/04 5.50 3 754 898 166 16 01/04-22/04 5.86 3 571 885 150 17 01/04-29/04 5.86 3 375 399 129 18 01/04-04/05 6.11 3 352 815 130 The sandeel fishery in 2009 was concentrated in three rectangles which accounted for about 70% of all landings. ICES reiterates its past observation that fisheries can cause local depletion of sandeel. Sandeel management in the North Sea is based on the invalid assumption that there is a single stock. There is strong evidence of a number of spatially distinct (sub-) stocks, although the full stock structure of sandeel in the North Sea remains unclear. It is known that sandeel (sub-) stocks on the Viking/Bergen Banks and in the western North Sea off Scotland are distinct, as is the (separatelymanaged) Shetland stock. Current knowledge for defining (sub-) stocks off south-west Norway and in the southern North Sea is too limited to recommend specific management measures for 2009 which can take into account the full stock structure of sandeel in the region. The model in Annex IID of COUNCIL REGULATION (EC) No 43/2009 was developed based on a more widely distributed fishery yearly landings for the period 1995 2008 distributed by ICES rectangle are shown in Figure 6.3.3.1.2. In 2009, the restricted spatial distribution of the fishery raises concerns about the validity of the current modelling approach and its reliance on a single index. These concerns further strengthen the argument for future spatial management in the sandeel fishery. Source of information ICES. 2007. ICES Advice, 2007. Copenhagen, Denmark. ICES. 2008a. ICES Advice, 2008. Copenhagen, Denmark. ICES. 2008b. Report of the Working Group on the Assessment of Demersal Stocks in the North Sea and Skagerrak Combined Spring and Autumn (WGNSSK). ICES CM 2008/ACFM:09 ICES. 2009. Report of the Ad hoc Group on Sandeel (AGSAN). Copenhagen, Denmark. ICES Advice 2009, Book 6 9

Figure 6.3.3.1.1. Landings weight from all available trips (left hand panel) and number of biological samples (right hand panel) by ICES rectangle for the Danish and Norwegian North Sea sandeel fishery. The area of the bubbles illustrates landings weight. The total landings weight (total:) and the maximum landing weight (max:) per rectangle are given as text (unit 1000 tonnes). The total and maximum number of samples by ICES rectangle are presented in the right hand panel (From ICES AGSAN 2009). 10 ICES Advice 2009, Book 6

Figure 6.3.3.1.2. Sandeel in Subarea IV. Landings of sandeel by year and ICES rectangles for the period 1995 2008. Landings include Danish and Norwegian landings for the whole period. Scottish landings are included from 1997 onwards; Swedish landings are included from 1998. Landings from other countries are negligible. The area of the circles corresponds to landings by rectangle. All rectangle landings are scaled to the largest rectangle landings shown in the 1995 map. The area that was closed to the sandeel fishery in 2000 and the boundary between the EU EEZ and the Norwegian EEZ are shown on the map (From ICES WGNSSK 2008b). ICES Advice 2009, Book 6 11

6.4 Stock Summaries 6.4.1 Cod in Division IIIa East (Kattegat) State of the stock Spawning biomass in relation to precautionary limits Reduced reproductive capacity Fishing mortality in relation to precautionary limits Fishing mortality in relation to high long-term yield Fishing mortality in relation to agreed target Unknown Unknown Unknown Comment Based on the most recent estimates of SSB (in 2009) ICES classifies the stock as suffering reduced reproductive capacity. The SSB trend indicates a fivefold decrease since 1970 and SSB has been at a historically low level since the early 2000s. Current level of fishing mortality is unknown. Recruitment in recent years has been the lowest in the time series. Management objectives In 2004, the European Commission enacted a Council Regulation (EC) No. 423/2004 which established measures for the recovery of cod stocks, including cod in the Kattegat. Council Regulation (EC) No 1342/2008 of 18 December 2008 (see Annex 6.4.1) established a long-term plan for cod stocks and the fisheries exploiting those stocks, repealing Regulation (EC) No 423/2004. The long term management plan requires implementation through Article 9 due to the current inability to estimate F. An exploratory evaluation (see section below) that assumed no bias in the TAC implementation shows that SSB will recover before 2015 to within precautionary limits; however, this evaluation is not expected to be realistic in a situation where unaccounted removals may be up to five times the TAC. In these circumstances ICES considers that a TAC constraint alone (under Article 9) is not precautionary. Reference points Type Value Technical basis B lim 6 400 t lowest observed SSB before the late 1990s. Precautionary B pa 10 500 t B lim *exp(1.645*0.3). approach F lim Not defined F pa Not defined Targets F mgt 0.4 EU management plan EC 1342/08 (unchanged since 2009) Single-stock exploitation boundaries Considering the options below, ICES advises on the basis of Exploitation boundaries in relation to precautionary considerations that there should be no catches of this stock in 2010. Exploitation boundaries in relation to existing management plans According to the long-term management plan, the fishing mortality in 2010 shall be reduced by 25 % compared with the fishing mortality rate in 2009, unless the target 0.4 is reached. The current level of fishing mortality on cod in the Kattegat cannot be reliably estimated. Where it is advised that the catches of cod should be reduced to the lowest possible level, the TACs shall be set according to a 25 % reduction compared to the TAC in the previous year, that corresponds to a TAC at 379 tonnes in 2010. Exploitation boundaries in relation to precautionary considerations Taking into account the current perception of the stock abundance and recruitment, fishing at any level will involve a risk of the stock remaining depleted. 12 ICES Advice 2009, Book 6

Short-term implications Due to uncertainty in the recent estimates, especially concerning fishing mortality, reliable predictions cannot be made. Management considerations Even though a management plan has been in place since 2005, the stock biomass has continued to decline. Total removals in the last 3 years have been estimated up to 5 times higher than the reported catches. No information is available on the nature of the unallocated removals but this information is essential to managers in order to take the appropriate management measures. Potential sources of unallocated removals are discarding of young ages and possibly also high-grading of marketable cod. Furthermore, migration of cod to other areas and not counted catches in recreational fisheries may explain the discrepancy between the reported catches and the estimates of total removals. Management plan evaluations ICES has conducted exploratory evaluation of the long-term management plan for cod in the Kattegat as specified by Council Regulation (EC) No 1342/2008 of 18 December 2008. The results showed that the present low TAC and the 20% TAC constraint in the long-term plan will allow a steep increase of SSB to above B pa even though scenario recruitment is assumed to be at a low level. This conclusion is based on no bias in the TAC implementation, which is not expected to be realistic. Due to uncertainties related to the historical and future bias in catch reporting and the extend of inflow of recruits from the North Sea stock and their homing at age 2-3 it is not possible to quantify the effect on the SSB of the local Kattegat stock spawning in the area. Factors affecting the fisheries and the stock Regulations and their effects Cod in Kattegat are mainly taken by trawls, Danish seines and gill-nets, Since 2004, the use of trawl with codend mesh sizes below 90 mm in the Nephrops fisheries has only been permitted if the trawl was equipped with a separator grid. This has resulted in a substantial decline of effort for this gear category. In 2007, Danish fishermen were allocated extra fishing days if using an exit-window with square-meshes at a minimum 120 mm; since 1 st February 2008, the usage of the exit-window in trawls has been made mandatory. The Danish minimum landing size was reduced to 30 cm in February 2008. In 2008, due to effort restrictions imposed between 1 February and 30 April the usage of trawls equipped with species sorting grid (which allows most cod to escape from the trawl) increased considerably, as this type of trawl is not effort regulated. These changes can be expected to have reduced discard of undersized cod, the effect can however not be evaluated due to uncertain discard estimates. Changes in fishing pattern in 2008 are believed to have reduced Swedish discards in 2008. Spatial and temporal fishing area closures were implemented in the Kattegat in January 2009 in order to reduce fishing mortality on cod. The effects of the spatial restrictions on cod recovery will be evaluated in three years time after the implementation. Impacts of the environment on the fish stock An analysis of the possible effect of environment and climate change on this stock has shown that fishing mortality has been the major driver of the long-term dynamics of the stock (Cardinale and Svedäng, 2004). Scientific basis Data and methods Reported landings and data from four scientific surveys were available for the assessment of this stock. Discard data are not used the assessment. The assessment is based on the recently developed stochastic state-space model (SAM) that provides statistically sound estimates of uncertainty in the model results. The model allows estimating potential additional removals from the stock, not represented by reported landings. The stock estimates for these years consequently rely more on survey information. The model estimates significant unallocated removals from the stock between 2003 and 2008. At present, the relative proportion of unallocated removals due to fishing and biology driven factors (migration patterns) cannot be specified. Therefore, both runs with and without estimating unallocated removals are presented (Figure 6.4.1.2 ). Estimates of F in either runs are not considered reliable. ICES Advice 2009, Book 6 13

Information from the fishing industry In December 2008, an extensive joint Swedish-Danish cod survey in Kattegat was conducted as collaboration between the fishing industry and fisheries research institutes of Denmark and Sweden. The data from this survey were used to provide an independent estimate of biomass of adult cod in the Kattegat (WKROUND 2009). The results were in line with the estimates from assessment, indicating low SSB (below 2000 tonnes). Uncertainties in assessment and forecast In recent years, reported landings appeared not to represent total removals from the stock. Significant bias in removals was estimated for 2003-2008. At present, the relative proportion of unallocated removals due to fishing and biology driven factors cannot be specified. Recent tagging studies suggest that the Kattegat may function as a nursery area for North Sea cod, and that return migration to the North Sea are common (Svedäng et al., 2006). There are some indications that the proportion of recruits of North Sea origin has increased in recent years. The migration of this stock component out of the area at an older age could contribute to the estimate of unallocated removals in the latest years. Because of these uncertainties, the current level of fishing mortality cannot be reliably estimated. Concerning SSB, the estimates are considered imprecise, however both the assessment with and without estimating unallocated removals indicate historically lowest SSB in recent years (in the range of 1413 and 3406 tonnes in 2008). The level of SSB estimated from assessment is in line with the independent estimates of cod biomass based on data from the joint Swedish-Danish fishermen-scientist survey conducted in 2008. In benchmark assessment 2009, the estimates of SSB showed also to be robust for uncertainties concerning natural mortality and discards of young fish. The assessment cannot be used as a basis for forecast. Comparison with previous assessment and advice The overall perception of the state of the stock is unchanged compared to last year. Therefore, the advice is similar to last year, i.e. there should be no catch on this stock in 2010. Sources of information Report of the Baltic Fisheries Assessment Working Group. Copenhagen, 22-28 April 2009 (ICES CM 2009/ACOM:07). Cardinale, M., and Svedäng, H. 2004. Modelling recruitment and abundance of Atlantic cod, Gadus morhua, in the eastern Skagerrak Kattegat (North Sea): evidence of severe depletion due to a prolonged period of high fishing pressure. Fisheries Research, 69: 263 282. Svedäng, H., Righton, D., and Jonsson, P. 2006. Return migrations of Atlantic cod (Gadus morhua L.) to the North Sea evidenced by archival tagging of cod off the eastern Skagerrak coast. ICES CM 2006/Q:06. WKROUND 2009. Report of the Benchmark and Data Compilation Workshop for Roundfish January 16 23 2009 Copenhagen, Denmark (ICES CM 2009/ACOM:32) 14 ICES Advice 2009, Book 6

Table 6.4.1.1 Cod in the Kattegat. Single stock exploitation boundaries (advice), management and landings. Year ICES Advice / 2005 onwards: Single-stock exploitation boundaries Predicted catch corresp. to advice Agreed TAC ICES landings 1987 Reduction in F < 13.0 15.5 11.5 1988 Reduction in F < 15.0 15 5.5 1989 TAC 10 12.5 8.6 1990 TAC 7 8.5 5.9 1991 TAC 6.3 6.65 6.8 1992 30% reduction in fishing effort - 6.65 6.3 1993 Limit fishing effort to 70% of 1991 effort - 6.8 7.2 1994 Reduction in catch from 1991 1992 < 6.3 6.8 6.7 7.8 1995 Precautionary TAC based on recent catches 6 7 6.7 8.2 1996 30% Reduction in fishing effort from 1994 level - 7.7 6.1 1997 Fishing effort should not exceed 70% of the 1994 level - 8.5 9.5 1998 Fishing effort should not exceed 70% of the 1994 level - 7.5 6.8 1999 F = 0.6 4.5 6.3 6.6 2000 At least 40% reduction in F 6.4 7 4.9 2001 F = Fpa = 0.6 4.7 6.2 3.9 2002 No fishery 0 2.8 2.3 2003 No fishery 0 2.3 2 2004 No fishery 0 1.363 1.4 2005 No fishery 0 1 1.1 2006 No fishery 0 0.85 0.9 2007 No fishery 0 0.731 0.6 2008 No catch 0 0.673 0.45 2009 No catch 0 0.505 2010 No catch 0 Weights in 000 t. 25,000 Landings (tonnes) 20,000 15,000 10,000 5,000 0 1971 1974 1977 1980 1983 1986 1989 1992 1995 1998 2001 2004 2007 Figure 6.4.1.1 Cod in the Kattegat: Reported landings in tonnes in 1971 2008. ICES Advice 2009, Book 6 15

SSB Fbar Recruitment, Age 1 Figure 6.4.1.2 Cod in the Kattegat. Mean SSB (t), Fbar and recruitment (Age 1, millions) from the runs with (black line) and without (red line) estimating unallocated removals. The latest estimate for SSB shown in the figure refers to the beginning of 2009. For Fbar and recruitment, the latest estimate is for 2008. Shaded area and broken lines represent 95% confidence intervals for the runs with and without estimating unallocated removals, respectively. Estimates of F in either runs are not considered reliable. Table 6.4.1.2 Cod in the Kattegat. Estimated scaling factors for removals from the stock (average and 95% confidence intervals, indicated as Low and High) Year Catch multiplier Low High 2003 1.61 1.14 2.27 2004 1.77 1.23 2.56 2005 3.67 2.53 5.33 2006 5.27 3.58 7.74 2007 4.66 3.13 6.92 2008 4.51 3.02 6.70 16 ICES Advice 2009, Book 6

Table 6.4.1.2 Cod in the Kattegat. Reported landings (in tonnes) in 1971 2008. Year Kattegat Denmark Sweden Germany 1 Total 1971 11,748 3,962 22 15,732 1972 13,451 3,957 34 17,442 1973 14,913 3,850 74 18,837 1974 17,043 4,717 120 21,880 1975 11,749 3,642 94 15,485 1976 12,986 3,242 47 16,275 1977 16,668 3,400 51 20,119 1978 10,293 2,893 204 13,390 1979 11,045 3,763 22 14,830 1980 9,265 4,206 38 13,509 1981 10,693 4,380 284 15,337 1982 9,320 3,087 58 12,465 1983 9,149 3,625 54 12,828 1984 7,590 4,091 205 11,886 1985 9,052 3,640 14 12,706 1986 6,930 2,054 112 9,096 1987 9,396 2,006 89 11,491 1988 4,054 1,359 114 5,527 1989 7,056 1,483 51 8,590 1990 4,715 1,186 35 5,936 1991 4,664 2,006 104 6,834 1992 3,406 2,771 94 6,271 1993 4,464 2,549 157 7,170 1994 3,968 2,836 98 7,802 2 1995 3,789 2,704 71 8,164 3 1996 4,028 2,334 64 6,126 4 1997 6,099 3,303 58 9,460 5 1998 4,207 2,509 38 6,835 1999 4,029 2,540 39 6,608 2000 3,285 1,568 45 4,897 2001 2,752 1,191 16 3,960 2002 1,726 744 3 2,470 2003 1,441 603 7 1 2,045 2004 827 575 1 1,403 2005 608 336 10 1,070 6 2006 540 315 21 876 2007 390 247 7 645 2008 296 152 1 449 1 Landings statistics incompletely split on the Kattegat and Skagerrak. 2 Including 900 t reported in Skagerrak. 3 Including 1.600 t misreported by area. 4 Excluding 300 t taken in Sub-divisions 22 24. 5 Including 1.700t reported in Sub-division 23. 6 Including 116 t reported as pollack 7 the catch reported to the EU exceeds the catch reported to the WG (shown in the table) by 40% ICES Advice 2009, Book 6 17

Annex 6.4.1 In December 2008 the European Council agreed on a new cod management plan implementing the new system of effort management and a target fishing mortality of 0.4 (EC 1342/2008). The HCR for setting TAC for the Kattegat cod stock are as follows: Article 6 The minimum spawning biomass level and the precautionary spawning biomass level for each of the cod stocks shall be as follows: Cod in the Kattegat Minimum spawning biomass Levels in tonnes 6 400 Precautionary spawning biomass Levels in tonnes 10 500 Article 7 Procedure for setting TACs for cod stocks in the Kattegat the west of Scotland and the Irish Sea 1. Each year, the Council shall decide on the TAC for the following year for each of the cod stocks in the Kattegat, the west of Scotland and the Irish Sea. The TAC shall be calculated by deducting the following quantities from the total removals of cod that are forecast by STECF as corresponding to the fishing mortality rates referred to in paragraphs 2 and 3: (a) a quantity of fish equivalent to the expected discards of cod from the stock concerned; (b) as appropriate a quantity corresponding to other sources of cod mortality caused by fishing to be fixed on the basis of a proposal from the Commission. 2. The TAC shall, based on the advice of STECF, satisfy all of the following conditions: (a) if the size of the stock on 1 January of the year of application of the TAC is predicted by STECF to be below the minimum spawning biomass level established in Article 6, the fishing mortality rate shall be reduced by 25 % in the year of application of the TAC as compared with the fishing mortality rate in the previous year; (b) if the size of the stock on 1 January of the year of application of the TAC is predicted by STECF to be below the precautionary spawning biomass level set out in Article 6 and above or equal to the minimum spawning biomass level established in Article 6, the fishing mortality rate shall be reduced by 15 % in the year of application of the TAC as compared with the fishing mortality rate in the previous year; and (c) if the size of the stock on 1 January of the year of application of the TAC is predicted by STECF to be above or equal to the precautionary spawning biomass level set out in Article 6, the fishing mortality rate shall be reduced by 10 % in the year of application of the TAC as compared with the fishing mortality rate in the previous year. 3. If the application of paragraph 2(b) and (c) would, based on the advice of STECF, result in a fishing mortality rate lower than the fishing mortality rate specified in Article 5(2), the Council shall set the TAC at a level resulting in a fishing mortality rate as specified in that Article. 4. When giving its advice in accordance with paragraphs 2 and 3, STECF shall assume that in the year prior to the year of application of the TAC the stock is fished with an adjustment in fishing mortality equal to the reduction in maximum allowable fishing effort that applies in that year. 5. Notwithstanding paragraph 2(a), (b) and (c) and paragraph 3, the Council shall not set the TAC at a level that is more than 20 % below or above the TAC established in the previous year. Article 9: Procedure for setting TACs in poor data conditions Where, due to lack of sufficiently accurate and representative information, STECF is not able to give advice allowing the Council to set the TACs in accordance with Articles 7 or 8, the Council shall decide as follows: (a) where STECF advises that the catches of cod should be reduced to the lowest possible level, the TACs shall be set according to a 25 % reduction compared to the TAC in the previous year; (b) in all other cases the TACs shall be set according to a 15 % reduction compared to the TAC in the previous year, unless STECF advises that this is not appropriate. 18 ICES Advice 2009, Book 6

Article 10: Adaptation of measures 1. When the target fishing mortality rate in Article 5(2) has been reached or in the event that STECF advises that this target, or the minimum and precautionary spawning biomass levels in Article 6 or the levels of fishing mortality rates given in Article 7(2) are no longer appropriate in order to maintain a low risk of stock depletion and a maximum sustainable yield, the Council shall decide on new values for these levels. 2. In the event that STECF advises that any of the cod stocks is failing to recover properly, the Council shall take a decision which: (a) sets the TAC for the relevant stock at a level lower than that provided for in Articles 7, 8 and 9; (b) sets the maximum allowable fishing effort at a level lower than that provided for in Article 12; (c) establishes associated conditions as appropriate. ICES Advice 2009, Book 6 19

6.4.2 Cod in Subarea IV (North Sea), Division VIId (Eastern Channel), and IIIa West (Skagerrak) State of the stock Spawning biomass in relation to precautionary limits Reduced reproductive capacity Fishing mortality in relation to precautionary limits Fishing mortality in relation to high longterm yield Fishing mortality in relation to agreed target Increased risk Overfished Above target Comment Based on the most recent estimate of SSB (in 2009) and fishing mortality (in 2008), ICES classifies the stock as suffering reduced reproductive capacity and as being at risk of being harvested unsustainably. SSB has increased since its historical low in 2006, but remains below B lim. Fishing mortality declined after 2000, but in 2008 increased, predominantly as a consequence of increased discarding and is currently estimated to be between F lim and F pa. The 2005 year class is estimated to be one of the most abundant amongst the recent below-average year classes. The 2008 year class is estimated to be one of the lowest in the series. Management objectives The EU Norway agreement management plan as updated in December 2008 aims to be consistent with the precautionary approach and is intended to provide for sustainable fisheries and high yield leading to a target fishing mortality to 0.4. (for details see Annex 6.4.2). The EU has adopted a long-term plan for this stock with the same aims (Council Regulation (EC) 1342/2008). ICES has evaluated the management plan in 2009 and considers it to be in accordance with the precautionary approach if it is implemented and enforced adequately. Discarding in excess of the assumptions under the management plan will affect the effectiveness of the plan. The evaluation is most sensitive to assumptions about implementation error (i.e. TAC and effort overshoot and the consequent increase in discards). Reference points Type Value Technical basis Precautionary approach B lim 70 000 t Bloss (~1995) B pa 150 000 t Bpa = Previous MBAL and signs of impaired recruitment below 150 000 t. F lim 0.86 Flim = Floss (~1995) F pa 0.65 Fpa = Approx. 5th percentile of Floss, implying an equilibrium biomass > Bpa. Targets F mgt 0.4 EU/Norway agreement and EU management plan 1342/08 (Unchanged since 1998, management plan target added in 2008) Yield and spawning biomass per Recruit F-reference points (2009): Fishing Mortality Yield/R SSB/R Ages 2-4 Average last 3 years 0.79 F max 0.25 0.69 2.1 F 0.1 0.16 0.69 3.2 F med 0.81 0.51 0.3 Estimated by ICES in 2009, assuming constant maturity, with M and stock weights averaged over the period 2000-2007. Selectivity is averaged over 2005-2007. 20 ICES Advice 2009, Book 6

In 2005, ICES advised that, on the basis of evaluations of harvest control rules for North Sea cod, target fishing mortalities (covering all catches) below 0.4 (ages 2 4) would result in a low risk of SSB falling below the conservation limit B lim and would achieve high long-term yields Single-stock exploitation boundaries Considering the options below, ICES advises on the basis of the management plan on an F in 2010 that is 65% of the F in 2008 (F2010=0.51), catches should be less 66 400 t. Assuming discards rates as observed in 2008, this implies landings of less than 40 300 t in 2010. This presumes that the objectives of the management plan are realised which assumes reduction in F and control of catches in 2009 and 2010. Exploitation boundaries in relation to existing management plans The plan stipulates that, based on the assumption that the 25% reduction in F in 2009 has been effective in reducing F 2009 to 25% below F 2008, the following criteria be met, in order of increasing priority: (a) TAC 2009 should not exceed a level that results in F 2010 being above 65% of F 2008 ; (b) There should be no more than a 20% change from TAC 2009 to TAC 2010 ; These criteria imply catches should be less 66 400 t. Assuming discards rates as observed in 2008, this implies landings of less than 40 300 t in 2010.This is less than the 20% increase constraint (1.2 TAC 2009 = 41 500t) for Area IV and Subdivisions VIId and IIIa (Skagerrak). Exploitation boundaries in relation to high long-term yield, low risk of depletion of production potential and considering ecosystem effects F 2008 is above the levels that would lead to high long-term yield and low risk of depletion of production potential, taking ecosystem effects into account. Exploitation boundaries in relation to precautionary limits Given the low stock size and recent poor recruitment, the stock cannot be rebuilt to B pa at the start of 2011 even with a zero catch. Simulations indicate that with the recent poor recruitment, a zero catch in 2010 and 2011 is likely to achieve the rebuilding of the stock to B pa by 2012. ICES Advice 2009, Book 6 21

22 ICES Advice 2009, Book 6 Short-term implications Outlook for 2010 Management plan assumptions Basis; F 09 = [management plan] = 0.75F 08 = 0.59 (land=0.29, disc=0.30); R 08-10 = (re-sampled from 1997-2007 YC, median of 1998-2008 YC) ~110 million; SSB(2010) = 66.0; Landings (2009) = 41.9; Discards (2009) = 24.8. Rationale Catches (2010) Landings (2010) Basis F total (2010) F land (2010) F disc (2010) Discards (2010) SSB (2011) %SSB change 1) %TAC change 2) Management F 10 = 66.4 40.3 0.51 0.25 0.26 26.1 79.6 21% 17% Plan 0.65*F 08 This option is considered precautionary in the context of the long term management plan. ICES assumptions Basis: F sq = F 06-08 scaled to F 08 = 0.79; R 08-10 = (re-sampled from 1997-2007 YC, median of 1998-2008 YC) ~110 million; SSB(2010) = 54.2; Landings (2009) = 51.5; Discards (2009) = 30.8. Rationale Catches (2010) Landings (2010) Basis F total (2010) F land (2010) F disc (2010) Discards (2010) SSB (2011) %SSB change 1) %TAC change 2) Zero Catch 0 0.0 F=0 0.00 0.00 0.00 0.0 113.5 110% -100% 46.8 27.9 0.50*Fsq 0.40 0.19 0.20 18.9 75.9 40% -19% 50.5 30.1 0.55*Fsq 0.44 0.21 0.22 20.4 72.9 35% -13% 54.3 32.3 0.60*Fsq 0.48 0.23 0.24 22.0 70.1 29% -7% 57.8 34.3 0.65*Fsq 0.51 0.25 0.26 23.4 67.2 24% -1% Status quo 61.1 36.2 0.70*Fsq 0.55 0.27 0.28 24.8 64.6 19% 5% options 64.2 38.1 0.75*Fsq 0.59 0.29 0.30 26.1 62.0 14% 10% 67.3 39.9 0.80*Fsq 0.63 0.31 0.32 27.4 59.6 10% 15% 70.5 41.8 0.85*Fsq 0.67 0.33 0.34 28.7 57.3 6% 21% 73.5 43.5 0.90*Fsq 0.71 0.35 0.36 30.0 55.1 2% 26% 79.1 46.7 Fsq 0.79 0.39 0.40 32.4 50.8-6% 35% Weights in 000 t. Shaded areas are not considered consistent with the precautionary approach in the short term. 1) SSB 2011 relative to SSB 2010. 2) Landings 2010 relative to TAC 2009 (Total = 34 590 t for the Skagerrak; VIId and IV; EC waters of IIa; that part of IIIa not covered by the Skagerrak and Kattegat) 22 ICES Advice 2009, Book 6

Management considerations The 2008 advice from ICES for this stock was a zero catch in 2009 because it did not consider the former recovery plan precautionary. The ICES advice for 2010 indicates that catches of cod can be allowed under the new management agreement. This change in advice is because the new management agreement is considered to be consistent with the precautionary approach. It should be emphasised that the new agreement is only consistent with the precautionary approach if it is implemented and enforced adequately. ICES has observed that there have been considerable problems with the effectiveness of the former recovery plan. Despite the objective of the plan to reduce fishing mortality and to increase the SSB by combined TAC control and effort management, estimated catches have been much higher than intended in the management plan. Although fishing mortality has been reduced after 2000, it has remained well above the targets implied by the plan and has increased again in 2008. Also discarding increased in 2007 and 2008 and contributed about half of the total fishing mortality in these years. Under the present implementation and enforcement approach, reduction in F and the recovery of the stock is unlikely under either management plan. It is therefore urgent to make significant improvements in implementation and enforcement to achieve reduction in F by effective control of cod catches. In recent years surveys indicate that the year classes are depleting faster than one would expect from the catches and point to unaccounted removals. There is no documented information on the source of these unaccounted removals; while it is assumed that these removals originate mostly from fishing activities, changes in natural mortality may also have an influence. Plausible fishery-based contributions to these unaccounted removals are discards that do not count against quota, and the mis- and under-reporting of catches (although the latter are considered to have reduced in recent years following changes to national reporting procedures). The recorded landings from 2005-2008 have fluctuated between 30% and 55% of the total removals. This indicates that the management system has not been effective in controlling the catches. Although the absolute levels of current SSB and fishing mortality are considered uncertain (Figure 6.4.2.1), fishing mortality rates have been reduced after 2000 and, due to the 2005 year class, the stock has increased since 2006. However, all recent year classes have been poor. The low average age of the spawning stock reduces its reproductive capacity, as first-time spawners reproduce less successfully than older fish which is considered to be a factor that has contributed to the continued low recruitment. In 2008, 94% of 1 year old, 73% of 2 year old, 64% of 3 year old (the abundant 2005 year class) and 12% of 4 year old cod (in numbers) were discarded. This resulted in discard mortality which exceeded landings mortality (Figure 6.4.2.2 and Figure 6.4.2.3). The recruitment of the relatively more numerous 2005 year-class to the fishery will have no beneficial effect on the current spawning biomass if it continues to be caught and heavily discarded. ICES notes that there have been considerable efforts to reduce discards by some countries, but it is too premature to evaluate the impact these have had in reducing discard mortality. It is important that the effectiveness of the existing measures is monitored and if discarding is still considered to be too high, then additional technical, temporal or spatial measures should be promptly introduced that are effective in reducing discards. The 2006 year class is locally abundant in the southern North Sea and Eastern Channel. This is causing high rates of discards and high-grading in 2008 and 2009 in the Eastern Channel. The 2006 year class is estimated as high as the 1996 year class in the Eastern Channel by the French ground fish survey but was found to be poor in the North Sea, based on the IBTS Q1 and Q3 surveys. Several nations, who make substantial landings of cod, have not supplied ICES with estimates of discards that can be used within the assessment process, despite the requirement to do so according to EU data collection regulations. In order to improve the quality of the assessment, and hence management advice, these nations should be encouraged to do so. Cod are taken by towed gears in mixed demersal fisheries, which include haddock, whiting, Nephrops, plaice, and sole. They are also taken in directed fisheries using fixed gears. For management to be effective, both species-specific assessments and the latest developments in mixed fisheries approaches need to be considered. A reduction in direct effort on one stock may lead to a reduction or an increase in effort on another and, hence, the implications of any changes need to be identified and carefully evaluated. Cod catch in Division VIId was managed by a TAC for Divisions VIIb-k,VIII, IX, X, and CECAF 34.1.1, (i.e. the TAC covers a small proportion of the North Sea cod stock together with cod in Divisions VIIe-k). Division VIId was allocated a separate TAC for 2009 which was adjusted in line with the revision to the North Sea TAC. ICES has developed a generic approach to evaluate whether new survey information that becomes available in September forms a basis to update the advice. If this is the case, ICES will publish new advice in November 2009. ICES Advice 2009, Book 6 23

Management plan evaluations In December 2008 the European Commission and Norway agreed on a new cod management plan implementing a new system of linked effort management with a target fishing mortality of 0.4 (EC 1342/2008 and Annex 6.4.2). ICES has evaluated the EC management plan in March 2009 and concluded that this management plan is in accordance with the precautionary approach only if implemented and enforced adequately. During the evaluation, ICES assumed that the annual effort reduction is fully achieved and the target F is achieved. Recovery is sensitive to assumptions about implementation error (i.e. scenarios of TAC and effort overshoot and increase in discards) and a continuation of the current low recruitment. Under these scenarios recovery to a precautionary status is delayed until after the required target date of 2015. The application of the 20% TAC constraint results in reductions in fishing mortality to values that are so low (e.g. F = 0.1 by ~ 2012) that it is impractical for effort to be reduced to the levels required, possibly even for by-catch fisheries. At such low levels of fishing, the behaviour of the mixed fishery is considered highly uncertain and the management plan evaluation assumptions will break down, especially with respect to discard practices. Removing the TAC constraint might reduce the level of discards and lead to more appropriate management and fishing practices but would also delay the recovery. Impacts of fisheries on the ecosystems Cod is targeted by a gillnet fishery, primarily conducted by Denmark and the UK, with a substantial bycatch of harbour porpoise. In 2001 the total bycatch in the cod fishery was around 2000 porpoises. Since 2001, effort reductions in this fishery have likely led to decreased bycatches of porpoises. The effect on the benthic invertebrate community in the northern North Sea from all otter trawling is estimated to represent an annual mortality of approximately 25% of the standing-crop biomass. The MAFCONS and STECF data set suggest that otter trawl effort directed at fish has declined since 1999 (Greenstreet et al., 2007). Factors affecting the fisheries and the stock Regulations and their effects Spatial management has been attempted for cod, both in the form of a closure of a large area of the North Sea in 2001 (Council Regulation (EC) 259/2001) and through implementation of a cod protection area in 2004 (EC 2287/2003). None of these measures appeared to have had the desired effect and both were abandoned shortly after implementation. In 2001, cod in the whole of NEAFC region 2 was a legitimate target species for towed gears with a minimum codend mesh size of 100 mm. As part of the cod recovery measures, the EU and Norway introduced additional technical measures from 1 January 2002 (EC 2056/2001). The basic minimum mesh size for towed gears for cod, apart from some transitional arrangements, has been 120 mm from 2002. This resulted in a shift in effort towards smaller meshed fisheries. Effort restrictions in the EC were introduced in 2003 (annual annexes to the TAC regulations) for the protection of the North Sea (?) cod stock. In 2009, the management program switched from a days at sea to a kw/day system (2009 Council Regulation (EC) N 43/2009), in which different amounts of kw/days are allocated within each area by Member State to different groups of vessels depending on gear and mesh size. In 2008, STECF indicated that overall effort (kw/days) by demersal trawls, seines and beam trawls had been substantially reduced since 2002. Fishing mortality declined between 2003 and 2007 concomitant with this effort reduction, but F increased again in 2008 despite a further nominal reduction in effort. Marked changes have also occurred in the use of the different mesh size categories by demersal trawlers. A sharp reduction has occurred in the use of mesh sizes between 100mm and 119mm, while a pronounced increase is apparent in the use of mesh sizes of 120mm and greater. As well, a general increase in effort has been observed in vessels using mesh sizes of 70-89mm and 90-99mm. Scotland implemented in February 2008 a national scheme known as the Conservation Credits Scheme. The principle of this two-part scheme involves additional time at sea in return for the adoption of measures which aims to reduce mortality on cod and lead to a reduction in discard numbers. ICES has not yet been able to evaluate the consequences of these measures. Despite their introduction, ICES notes that during the initial year of operation (2008) cod discarding rates increased substantially. A new rights-based regulation (FKA Vessel Quota Share) was put in force in Denmark from the 1st January 2007. With the new system, individual vessels are allocated a yearly share of the Danish quota, which can be taken at any time 24 ICES Advice 2009, Book 6

of the year. There is also a possibility to trade it, exchange it, or pool it with other fishers. The old regulation had a system with 14-day quotas, which continuously adjusted to the amount of national quota left. The new system gives the industry a possibility to plan better and is expected to lead to a more efficient fishery with less discards. ICES has not yet been able to evaluate the consequences of these measures. Changes in fishing technology and fishing patterns WGFTFB (ICES, 2009) note that the decline in fuel costs from 2008 to 2009 have influenced the operational dynamics of some fleets that traditionally target mixed demersal species in the North Sea by lowering the costs associated with fishing in more distant areas. This has been further enhanced by the introduction of a more restrictive effort regime in IV, VIId and VIa and the absence of effort restrictions in other areas. These factors are thought to have contributed to a shift in effort away from IV towards fisheries in Rockall, the Celtic Sea and the Porcupine. The extent of the effort transfer cannot currently be quantified, but is likely to be significant and fishing patterns in 2009 may be very different to those observed in 2008.. The expected benefits from the increase in mesh size to 120 mm are not apparent from the available data. The effect of this increase is confounded by the transfer of effort from the fleets fishing with mesh sizes >120 mm to fleets fishing with mesh sizes between 70 and 99 mm, i.e. fishing for Nephrops. The regulation differentiated between the number of fishing days allowed when fishing for Nephrops or when fishing for other demersal species (>120 mm). Fishing for Nephrops with the smaller mesh allowed more days at sea than fishing with larger meshes. The introduction of the one-net rule as part of the Scottish Conservation Credit Scheme is likely to improve the accuracy of reporting of metier-based landings. Scottish legislation implemented in January 2008, banning the use of multi-rigs (>2 rigs per trawl), could limit the potential of uncontrolled increase in effort. There has also been a move in Scottish vessels from using 100 110 mm for whitefish on west coast ground (Subarea VI) to the North Sea using 80 mm prawn codends, which could imply increased discarding. A move from the Farn Deeps Nephrops fishery into other fisheries for whitefish because of poor Nephrops catch rates, implies increased effort in whitefish fisheries. Impacts of the environment on the fish stock The North Sea has seen a northerly shift in the mean latitudinal distribution of the stock. However, the evidence for this in the form of a migratory response is slight or non-existent. More likely, cod in the North Sea are composed of a complex of more or less isolated sub-stocks and the southern units have been subjected to disproportionately high rates of fishing mortality. The contracted range of the North Sea cod stock can be linked to reduced abundance as well as climate factors. The consumption of cod in the North Sea in 2002 by grey seals has recently been estimated (Hammond and Grellier, 2006). For the North Sea it was estimated that in 1985 grey seals consumed 4150 tonnes of cod (95% confidence intervals; 2484 5760 tonnes), and in 2002 the population tripled in size (21 000 68 000 individuals) and consumed 8344 tonnes (95% confidence intervals; 5028 14 941 tonnes). Inclusion of the new grey seal diet data and seal population abundance are expected to reduce slightly the historic estimates of cod consumption in the North Sea by seals, generated from a multispecies model previously used. This suggests that the new estimates of seal predation will not alter the current perception of North Sea cod stock dynamics. Scientific basis Data and methods The age-based assessment model (B-ADAPT) used landings and discards, calibrated with two survey indices (from IBTS quarter 1 and quarter 3 surveys). For ICES Subarea IV and Division VIId, discards were estimated from the Scottish discards sampling programme up until 2005 and raised to the total international fleet. For 2006 Denmark provided its own discard estimates. For 2007 and 2008 Scottish, Danish, German, and England and Wales discard estimates were combined and used to raise landings-at-age for remaining nations in Subarea IV. Discards in Division IIIa were based on observer estimates. For 2006-2008, Danish and Swedish discard estimates were combined to raise landings-at-age from the remaining nations in Division IIIa. The assessment and forecast made use of the 2009 Quarter 1 IBTS survey. Because of unreliable information on landings and effort, commercial indices were not used in the assessment. Instead, the assessment uses only survey data for calibration. The natural mortality values used in the assessment have been revised based on new estimates from the multi-species model. Quantities of additional unallocated removals were estimated by the model on the basis of the total mortality indicated by the survey. In addition to the B-ADAPT model a new model (state space SAM model) was used ICES Advice 2009, Book 6 25

to validate the estimates of unallocated removals. Both models gave similar estimates of SSB and total F although there were differences in unallocated removals. The unallocated removals estimates could potentially include components associated to increased natural mortality and discarding as well as unreported landings. It is, however, assumed that all of these removals originate from fishing activities. A series of medium-term projections were used to evaluate management scenarios. The catch options in the forecast table represent median values from the projections. All scenarios assume a 25% reduction in fishing mortality in 2009 to account for a 25% reduction in effort for the main cod gears, as stipulated in EC 1342/2008. Landings and discards in the forecast are estimated by applying the landing- and discard-at-age ratios for 2008 to total fishing mortality-at-age for the projection period. Figures 6.2.2.3a and b illustrate two scenarios, one with constant fishing at the 2009 level (Figures 6.4.2.3a) and the other a closure from 2010 onwards (Figures 6.4.2.3b). The closure option is expected to bring SSB above B lim in 2012 with 95% probability. Information from the fishing industry Comparison between the fishers North Sea Stock Survey and the IBTS survey data has been shown in previous years the time series are broadly in agreement in recording a stable overall stock abundance until 2003-2005 followed by an increase more recently, especially in the north-western North Sea. The IBTS surveys have more variability, due to the inherent spatial variation, but exhibit similar trends in the same areas as the fishers survey, with significant increases in the north and west. In May 2008, French fishers targeting cuttlefish in the eastern Channel reported discards of several tonnes per haul of undersized cod in ICES rectangle 28F0, forcing them to leave their usual cuttlefish fishing area. They reported that this also occurred in 2007. Data collected in the Channel by French fishers and submitted to the ICES WGNSSK in 2009 indicate high rates of discards for lengths between 37 and 48cm (ages 2 and 3), confirming the information from previous years and indicate recent improved recruitment and survivorship in the southern North Sea and VIId. Uncertainties in assessment and forecast A large part (approximately 50% in 2007 and 2008) of the total catch used in the assessment is discards estimated from relatively low sample numbers compared to landings, and through estimation of unallocated mortality rates. Raised discard information was not available for a major component of the catch in the southern part of the North Sea and in the eastern Channel from French fleets. These are sources of added uncertainty in the assessment. Comparison with previous assessment and advice: The fishing mortality for 2007 has been revised downwards by 3% compared to the last assessment (May 2008) while SSB in 2008 was revised upwards by 15%. The F 2008 estimate, at 0.79 is a 36% increase on the F 2008 (0.58) used for the previous years' forecast, which was based on the 10% reduction in fishing effort in 2008 imposed in that year. The natural mortality values used in the assessment have been revised based on new estimates from the multi-species model.. The basis for the advice has changed from precautionary limits to the management plan since this was evaluated in 2009 and found to be consistent with the precautionary approach when implemented and enforced adequately. Sources of information Report of the Working Group on the Assessment of Demersal Stocks in the North Sea and Skagerrak, 6-12 May 2009 (ICES CM 2009/ACOM:10). Greenstreet, S., Robinson, L., Piet, G., Craeymeersch, J., Callaway, R., Reiss, H., Ehrich, S., Kröncke, I., Fraser, H., Lancaster, J., Jørgensen, L., and Goffin, A. 2007. The ecological disturbance caused by fishing in the North Sea. Fisheries Research Services, Aberdeen, U.K. Collaborative Report No. 04/07, 169 pp. Grellier, K., and Hammond, P. S. 2006. Robust digestion and passage rate estimates for hard parts of grey seal (Halichoerus grypus) prey. Canadian Journal of Fisheries and Aquatic Sciences, 63: 1982 1998. ICES 2009, ICES FAO Working Group on Fishing Technology and Fish Behaviour [WGFTFB], (ICES CM 2009/ FTC:06). STECF PLEN-08-03 EUR 23624 EN, ISBN 978-79-10940-9, ISSN 1018-5593, DOI 10.2788/3484, 2008 26 ICES Advice 2009, Book 6

ICES Advice 2009, Book 6 27 Table 6.4.2.1 North Sea (Subarea IV) Year ICES Advice Cod in Subarea IV (North Sea), Division VIId (Eastern Channel), and Division IIIa (Skagerrak). Single-stock exploitation boundaries (advice), management, and catch/landings. Landings for each of the three parts of this combined-area assessment, and for all areas combined are given in Table 6.4.2.2. Single-stock exploitation boundaries Predicted catch corresponding to advice Predicted catch corresp. to singlestock exploitation boundaries ICES Advice 2009, Book 6 27 Agreed TAC Official landings 1987 SSB recovery; TAC 100 125 175 167 182 1988 70% of F(86); TAC 148 160 142 157 1989 Halt SSB decline; protect juveniles; TAC 124 124 110 116 1990 80% of F (88); TAC 113 105 99 105 1991 70% of effort (89) 100 87 89 1992 70% of effort (89) 100 98 97 1993 70% of effort (89) 101 94 105 1994 Significant effort reduction 102 87 95 1995 Significant effort reduction 120 112 120 1996 80% of F(94) = 0.7 141 130 104 107 1997 80% of F(95) = 0.65 135 115 100 102 1998 F(98) should not exceed F(96) 153 140 114 122 1999 F = 0.60 to rebuild SSB 125 132 80 78 2000 F less than 0.55 < 79 81 62 59 2001 lowest possible catch 0 48.6 42.3 41 2002 lowest possible catch 0 49.3 44.2 44.3 2003 Closure 0 27.3 27.4 NA 2004 Zero catch Zero catch 0 0 27.3 23.4 NA 2005 Zero catch Zero catch 0 0 27.3 23.9 NA 2006 Zero catch Zero catch 0 0 23.2 22.2 NA 2007 Zero catch Zero catch 0 0 20.0 19.7 NA 2008 Exploitation boundaries in relation to precautionary limits Total removals < 22 000 t 2009 Zero catch Zero catch 0 0 28.8 2010 Management plan F (65% of F2008) < 40.3 1) Weights in 000 t. 1) For Subarea IV (North Sea), Division VIId (Eastern Channel), and Division IIIa (Skagerrak) < 22 < 22 22.2 22.2 NA ICES landings

28 ICES Advice 2009, Book 6 Skagerrak (Division IIIa) Year ICES Advice 28 Single-stock exploitation boundaries Predicted catch corresponding to advice Predicted catch corresp. to singlestock exploitation boundaries Agreed TAC 1 Official landings 1987 F = F max <21 22.5 19.9 20.9 1988 Reduce F 21.5 17.0 16.9 1989 F at F med <23 20.5 18.7 19.6 1990 F at F med ; TAC 21.0 21.0 17.8 18.6 1991 TAC 15.0 15.0 12.1 12.4 1992 70% of F(90) 15.0 14.0 14.8 1993 Precautionary TAC 15.0 14.7 15.3 1994 No long-term gain in increased F + precautionary TAC 15.5 13.3 13.9 1995 If required precautionary TAC; link to North Sea 20.0 12.1 12.1 1996 If required precautionary TAC; link to North Sea 23.0 16.2 16.4 1997 If required precautionary TAC; link to North Sea 16.1 14.9 14.9 1998 If required precautionary TAC; link to North Sea 21.9 20.0 15.3 15.3 1999 F = 0.60 to rebuild SSB 17.9 19.0 11.0 11.0 2000 F less than 0.55 <11.3 11.6 9.3 9.3 2001 lowest possible catch 0 7.0 7.1 7.1 2002 lowest possible catch 0 7.1 7.5 7.5 2003 Closure 0 3.9 3.8 NA 2004 Zero catch Zero catch 0 0 3.9 3.8 NA 2005 Zero catch Zero catch 0 0 3.9 3.8 NA 2006 Zero catch Zero catch 0 0 3.3 3.4 NA 2007 Zero catch Zero catch 0 0 2.9 2.9 NA 2008 Exploitation boundaries in relation to precautionary limits Total removals less than < 22 < 22 3.2 3.3 NA 22 000 t 2009 Zero catch Zero catch 0 0 4.1 2010 Management plan F (65% of F2008) < 40.3 2) Weights in 000 t. 1) Norwegian fjords not included. 2) For Subarea IV (North Sea), Division VIId (Eastern Channel), and Division IIIa (Skagerrak) ICES landings 1 ICES Advice 2009, Book 6

ICES Advice 2009, Book 6 29 Eastern Channel (Division VIId) Year ICES Advice Single-stock exploitation boundaries Predicted catch corresponding to advice Predicted catch corresp. to singlestock exploitation boundaries ICES Advice 2009, Book 6 29 Agreed TAC 1) Official landings 1987 Not assessed - - 9.4 14.2 1988 Precautionary TAC - - 10.1 10.7 1989 No increase in F; TAC 10.0 2) - n/a 5.5 1990 No increase in F; TAC 9.0 2) - n/a 2.8 1991 Precautionary TAC 3.0 2) - n/a 1.9 1992 If required, precautionary TAC 5.5 2) - 2.7 2.7 1993 If TAC required, consider SSB decline - - 2.5 2.4 1994 Reduce F+ precautionary TAC - 2.9 2.9 1995 Significant effort reduction; link to North Sea - 4.0 4.0 1996 Reference made to North Sea advice - 3.5 3.5 1997 No advice - 7.2 7.0 1998 Link to North Sea 4.9-8.7 8.6 1999 F = 0.60 to rebuild SSB 4.0 - n/a 6.9 2000 F less than 0.55 < 2.5-3.6 2.3 2001 lowest possible catch 0-2.0 1.6 2002 lowest possible catch 0-1.6 3.1 2003 Closure 0-1.3 NA 2004 Zero catch Zero catch 0 0-0.2 NA 2005 Zero catch Zero catch 0 0-0.7 NA 2006 Zero catch Zero catch 0 0-1.1 NA 2007 Zero catch Zero catch 0 0-1.7 NA 2008 Exploitation boundaries in relation to precautionary limits Total removals less than 22 000 t < 22 < 22-1.4 NA 2009 Zero catch Zero catch 0 0 1.7 2010 Management plan F (65% of F2008) < 40.3 3) Weights in 000 t. 1) Until 2008 this area was included in TAC for Subarea VII (except Division VIIa), from 2009 a separate TAC is set. 2) Including Division VIIe. 3) For Subarea IV (North Sea), Division VIId (Eastern Channel), and Division IIIa (Skagerrak) ICES landings

300000 SSB 1.4 F(2-4) 250000 1.2 200000 1 0.8 150000 0.6 100000 0.4 50000 0.2 0 1960 1965 1970 1975 1980 1985 1990 1995 2000 2005 2010 0 1960 1965 1970 1975 1980 1985 1990 1995 2000 2005 2010 1400000 TSB 700000 Catch 1200000 600000 1000000 500000 800000 400000 600000 300000 400000 200000 200000 100000 0 1960 1965 1970 1975 1980 1985 1990 1995 2000 2005 2010 0 1960 1965 1970 1975 1980 1985 1990 1995 2000 2005 2010 3000000 3 R (age 1) Catch multiplier 2500000 2.5 2000000 2 1500000 1.5 1000000 1 500000 0.5 0 1960 1965 1970 1975 1980 1985 1990 1995 2000 2005 2010 0 1993 1995 1997 1999 2001 2003 2005 2007 Figure 6.4.2.1 Cod in Subarea IV (North Sea), Division VIId (Eastern Channel), and Division IIIa (Skagerrak). Clockwise from top left: percentiles (5,25,50,75,95) of the estimated spawning-stock biomass (SSB), total stock biomass (TSB), recruitment (R(age 1)), and the catch multiplier, catch, and mean fishing mortality for ages 2 4 (F(2 4)) from the B-ADAPT base run. The heavy lines represent the bootstrap median, the light broken lines the 25th and 75th percentiles, and the heavy broken lines the 5th and 95th percentiles. The solid diamonds represent point estimates, and the open diamonds given in the catch plot the recorded total catch. The horizontal broken lines in the SSB plot indicate B lim = 70 000 t and B pa = 150 000 t, and those in the F(2 4) plot F pa = 0.65 and F lim = 0.86. The horizontal solid line in the catch multiplier plot indicates a multiplier of 1. Catch, SSB, and TSB are in tonnes, R is in thousands. 30 ICES Advice 2009, Book 6

1.6 F(2-4) 1.2 landings 0.8 0.4 0 discards 1960 1965 1970 1975 1980 1985 1990 1995 2000 2005 2010 1.6 Discards Landings F (2-4) 1.2 0.8 0.4 0 1963 1968 1973 1978 1983 1988 1993 1998 2003 2008 Figure 6.4.2.2 Cod in Subarea IV, Divisions IIIa (Skagerrak) and VIId. The mean fishing mortality for ages 2-4 separated into landings and discards components by using ratios calculated from the landings and discards numbers at age from the reported catch data. The top panel shows bootstrap medians (heavy lines) with 25th and 75th percentiles (light broken lines), and 5th and 95th percentiles (heavy broken lines), while the bottom panel shows a stacked-area plot of the bootstrap medians. ICES Advice 2009, Book 6 31

1 Proportion discarded at age (by number) age 1 0.8 0.6 age 2 0.4 0.2 age 3 age 4 0 1960 1965 1970 1975 1980 1985 1990 1995 2000 2005 2010 Figure 6.4.2.3 Cod in Subarea IV and Divisions IIIa (Skagerrak) and VIId: Proportion of total numbers caught at age that are discarded. In 2008, 94% of 1 year old, 73% of 2 year old, 64% of 3 year old (the abundant 2005 year class) and 12% of 4 year old cod, were discarded. 32 ICES Advice 2009, Book 6

Constant F Fbar(2-4) Catch/Removals (Tonnes) 1.600 1.400 1.200 1.000 0.800 0.600 0.400 0.200 0.000 1960 1970 1980 1990 2000 2010 2020 700000 600000 500000 400000 300000 200000 100000 0 1960 1970 1980 1990 2000 2010 2020 SSB Recruitment 300000 250000 200000 150000 100000 50000 0 1960 1970 1980 1990 2000 2010 2020 1960 1970 1980 1990 2000 2010 2020 Closure Fbar(2-4) Catch/Removals (Tonnes) 1.600 1.400 1.200 1.000 0.800 0.600 0.400 0.200 0.000 1960 1970 1980 1990 2000 2010 2020 700000 600000 500000 400000 300000 200000 100000 0 1960 1970 1980 1990 2000 2010 2020 SSB Recruitment 300000 250000 200000 150000 100000 50000 0 1960 1970 1980 1990 2000 2010 2020 1960 1970 1980 1990 2000 2010 2020 Figure 6.4.2.4a Cod in Subarea IV (North Sea), Division VIId (Eastern Channel), and Division IIIa (Skagerrak). B-ADAPT forecast for a reduction in fishing mortality by 25% from 2009, followed by Top 4 graphs; constant fishing mortality at the 2009 level for 2010 onwards. Bottom 4 graphs; a closure of the fishery for 2009 onwards. Broken lines represent bootstrap percentiles (5,25,75,95), and the solid trajectory the median. ICES Advice 2009, Book 6 33

Stock - Recruitment Recruitment (age 1) in billions 3 2.5 2 1.5 1 0.5 0 0 50 100 150 200 250 300 SSB in 1000 t SSB-Rec. Blim Bpa 300 250 Precautionary Approach Plot Period 1963-2008 SSB in 1000 t 200 150 100 50 0 0.0 0.2 0.4 0.6 0.8 1.0 1.2 1.4 Fishing Mortality (ages 2-4) F-SSB 2008 Flim Fpa Blim Bpa Figure 6.4.2.5 Cod in Subarea IV (North Sea), Division VIId (Eastern Channel), and Division IIIa (Skagerrak). Spawning stock recruitment and precautionary approach plot. 34 ICES Advice 2009, Book 6

Figure 6.4.2.6 Cod in Subarea IV (North Sea), Division VIId (Eastern Channel), and Division IIIa (Skagerrak). Results of the North Sea Commission fishers survey 2008. 200 180 160 SSB ('000 tonnes) 1.40 1.20 Fishing mortality: 2-4 1200 1000 Millions Recruitment. Age: 1 140 120 1.00 0.80 800 100 80 0.60 600 60 0.40 400 40 20 0.20 200 0 1990 1995 2000 2005 0.00 1990 1995 2000 2005 0 1990 1995 2000 2005 Figure 6.4.2.7 Cod in Subarea IV (North Sea), Division VIId (Eastern Channel), and Division IIIa (Skagerrak). Historical performance of the assessment. ICES Advice 2009, Book 6 35

Table 6.4.2.2 Cod in Subarea IV (North Sea), Division VIId (Eastern Channel), and Division IIIa (Skagerrak). Nominal landings (in tonnes) of COD, 1989 2008, as officially reported to ICES, and as used by the Working Group. Sub-area IV Country 1989 1990 1991 1992 1993 1994 1995 1996 1997 1998 Belgium 3,398 2,934 2,331 3,356 3,374 2,648 4,827 3,458 4,642 5,799 Denmark 25,782 21,601 18,997 18,479 19,547 19,243 24,067 23,573 21,870 23,002 Faroe Islands 35 96 23 109 46 80 219 44 40 102 France 2,578 1,641 975 2,146 1,868 1,868 3,040 1,934 3,451 2,934 Germany 11,430 11,725 7,278 8,446 6,800 5,974 9,457 8,344 5,179 8,045 Greenland - - - - - - - - - - Netherlands 12,028 8,441 6,831 11,133 10,220 6,512 11,199 9,271 11,807 14,676 Norway 4,813 5,168 6,022 10,476 8,742 7,707 7,111 5,869 5,814 5,823 Poland 24 53 15 - - - - 18 31 25 Sweden 501 620 784 823 646 630 709 617 832 540 UK (E/W/NI) 18,035 15,593 14,249 14,462 14,940 13,941 14,991 15,930 13,413 17,745 UK (Scotland) 31,828 31,187 29,060 28,677 28,197 28,854 35,848 35,349 32,344 35,633 Total Nominal Catch 110,452 99,059 86,565 98,107 94,380 87,457 111,468 104,407 99,423 114,324 Unallocated landings 5,248 5,692 1,968-758 10,200 7,066 8,555 2,161 2,746 7,779 WG estimate of total landings 115,700 104,751 88,533 97,349 104,580 94,523 120,023 106,568 102,169 122,103 Agreed TAC 124,000 105,000 100,000 100,000 101,000 102,000 120,000 130,000 115,000 140,000 Division VIId Country 1989 1990 1991 1992 1993 1994 1995 1996 1997 1998 Belgium 173 237 182 187 157 228 377 321 310 239 Denmark <0.5 - - 1-9 - - - - France... 2,079 1,771 2,338 3,261 2,808 6,387 7,788 Netherlands 1 - - 2 - - - - - 19 UK (E/W/NI) 563 422 341 443 530 312 336 414 478 618 UK (Scotland) - 7 2 22 2 <0.5 <0.5 4 3 1 Total Nominal Catch 737 666 525 2,734 2,460 2,887 3,974 3,547 7,178 8,665 Unallocated landings 4,801 2,097 1,361-65 -28-37 -10-44 -135-85 WG estimate of total landings 5,538 2,763 1,886 2,669 2,432 2,850 3,964 3,503 7,043 8,580 Division IIIa (Skagerrak)** Country 1989 1990 1991 1992 1993 1994 1995 1996 1997 1998 Denmark 16,634 15,819 10,294 11,187 11,994 11,921 15,888 14,573 12,159 12,339 Germany - 58 3-530 399 285 259 81 54 Norway 1,003 1,061 924 1,208 1,043 850 1,039 1,046 1,323 1,293 Sweden 1,805 1,136 3,846 2,523 2,575 1,834 2,483 1,986 2,173 1,900 Others 34 76 38 102 88 71 134 - - - Norwegian coast * 888 846 854 923 909 760 846 748 911 976 Danish industrial by-catch * 428 687 953 1,360 511 666 749 676 205 97 Total Nominal Catch 19,476 18,150 15,105 15,020 16,230 15,075 19,829 17,864 15,736 15,586 Unallocated landings -779-350 -3,046-1,018-1,493-1,814-7,720-1,615-790 -255 WG estimate of total landings 18,697 17,800 12,059 14,002 14,737 13,261 12,109 16,249 14,946 15,331 Agreed TAC 20,500 21,000 15,000 15,000 15,000 15,500 20,000 23,000 16,100 20,000 Sub-area IV, Divisions VIId and IIIa (Skagerrak) combined 1989 1990 1991 1992 1993 1994 1995 1996 1997 1998 Total Nominal Catch 130,665 117,875 102,195 115,861 113,070 105,419 135,271 125,818 122,337 138,575 Unallocated landings 9,271 7,439 283-1,841 8,679 5,215 825 502 1,821 7,439 WG estimate of total landings 139,936 125,314 102,478 114,020 121,749 110,634 136,096 126,320 124,158 146,014 ** Skaggerak/Kattegat split derived from national statistics * The Danish industrial by-catch and the Norwegian coast catches are not included in the (WG estimate of) total landings of Division IIIa. Magnitude not available - Magnitude known to be nil <0.5 Magnitude less than half the unit used in the table n/a Not applicable Division IIIa (Skagerrak) landings not included in the assessment Country 1989 1990 1991 1992 1993 1994 1995 1996 1997 1998 Norwegian coast * 888 846 854 923 909 760 846 748 911 976 Danish industrial by-catch * 428 687 953 1,360 511 666 749 676 205 97 Total 1,316 1,533 1,807 2,283 1,420 1,426 1,595 1,424 1,116 1,073 36 ICES Advice 2009, Book 6

Table 6.4.2.2.cont Cod in Subarea IV (North Sea), Division VIId (Eastern Channel), and Division IIIa (Skagerrak). Nominal landings (in tonnes) of COD, 1989 2008, as officially reported to ICES, and as used by the Working Group. Sub-area IV Country 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 Belgium 3,882 3,304 2,470 2,616 1,482 1,627 1,722 1,309 1,009 890 Denmark 19,697 14,000 8,358 9,022 4,676 5,889 6,291 5,105 3,430 3,828 Faroe Islands 96. 9 34 36 37 34 3 - - France. 1,222 717 1,777 620 294 664 354 659 631 Germany 3,386 1,740 1,810 2,018 2,048 2,213 2,648 2,537 1,899 1,736 Greenland - - - - - - 35 23.. Netherlands 9,068 5,995 3,574 4,707 2,305 1,726 1,660 1,585 1,523 1,896 Norway 7,432 6,410 4,369 5,217 4,417 3,223 2,900 2,749 3,057 4,128 Poland 19 18 18 39 35 - - - 1 2 Sweden 625 640 661 463 252 240 319 309 387 435 UK (E/W/NI) 10,344 6,543 4,087 3,112 2,213 1,890 1,270 1,491 1,587 n/a UK (Scotland) 23,017 21,009 15,640 15,416 7,852 6,650 4,936 6,857 6,511 n/a UK (combined) n/a n/a n/a n/a n/a n/a n/a n/a n/a 8,727 Others - - - - - - - 786.. Norwegian indust by-catch *....... 48 101 22 Danish industrial by-catch *....... 34 18 46 Total Nominal Catch 77,566 60,881 41,713 44,421 25,936 23,789 22,479 23,108 20,063 22,272 Unallocated landings 826-1,114-740 -121-89 -240 1,391-915 -380-78 WG estimate of total landings 78,392 59,767 40,973 44,300 25,847 23,549 23,870 22,193 19,683 22,195 Agreed TAC 132,400 81,000 48,600 49,300 27,300 27,300 27,300 23,205 19,957 22,152 Division VIId Country 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 Belgium 172 110 93 51 54 47 51 80 84 155 Denmark - - - - - - - - - - France. 3,084 1,677 1,361 1,730 810 986 1,124 1,735 760 Netherlands 3 4 17 6 36 14 9 9 59 30 UK (E/W/NI) 454 385 249 145 121 103 184 270 175 n/a UK (Scotland) - - - - - - - 2 12 n/a UK (conbined) n/a n/a n/a n/a n/a n/a n/a n/a n/a 151 Total Nominal Catch 629 3,583 2,036 1,563 1,941 974 1,230 1,485 2,065 1,096 Unallocated landings 6,229-1,258-463 1,534-707 -167-197 -358-325 258 WG estimate of total landings 6,858 2,325 1,573 3,097 1,234 807 1,033 1,127 1,740 1,354 Division IIIa (Skagerrak)** Country 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 Denmark 8,682 7,656 5,870 5,511 3,054 3,009 2,984 2,478 2,228 2,534 Germany 54 54 32 83 49 99 86 84 67 52 Norway 1,146 926 762 645 825 856 759 628 681 779 Sweden 1,909 1,293 1,035 897 510 495 488 372 370 365 Others - - - - 27 24 21 373 385 13 Norwegian coast * 788 624 846.. 720 759 524 494 499 Danish industrial by-catch * 62 99 687.. 10 18 9.. Total Nominal Catch 11,791 9,929 7,699 7,136 4,465 4,483 4,338 3,935 3,731 3,743 Unallocated landings -817-652 -613 332-674 -696-533 -569-785 -445 WG estimate of total landings 10,974 9,277 7,086 7,468 3,791 3,787 3,805 3,366 2,946 3,298 Agreed TAC 19,000 11,600 7,000 7,100 3,900 3,900 3,900 3,315 2,851 3,165 Sub-area IV, Divisions VIId and IIIa (Skagerrak) combined 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 Total Nominal Catch 89,986 74,393 51,448 53,120 32,342 29,246 28,047 28,528 25,859 27,112 Unallocated landings 6,239-3,024-1,816 1,745-1,470-1,103 661-1,842-1,490-264 WG estimate of total landings 96,225 71,369 49,632 54,865 30,872 28,143 28,708 26,686 24,369 26,847 ** Skaggerak/Kattegat split derived from national statistics * The Danish and Norwegian industrial by-catch and the Norwegian coast catches are not included in the (WG estimate of) total landings. Magnitude not available - Magnitude known to be nil <0.5 Magnitude less than half the unit used in the table n/a Not applicable Division IV and IIIa (Skagerrak) landings not included in the assessment Country 1999 2000 2001 2002 2002 2004 2003 2006 2007 2008 Norwegian coast * 788 624 846.. 720 759 524 494 499 Norwegian indust by-catch *....... 48 101 22 Danish industrial by-catch * 62 99 687.. 10 18 43 18 46 Total 850 723 1,533.. 730 777 615 613 567 ICES Advice 2009, Book 6 37

Table 6.4.2.3 Cod in Subarea IV (North Sea), Division VIId (Eastern Channel), and Division IIIa (Skagerrak). Landings, discards, and estimated total removals in tonnes. Landings Discards Catch (L+D) Total estimated removals 1985 214.6 31.5 246.1 247.0 1986 204.1 139.1 343.1 341.0 1987 216.2 27.8 244.1 244.8 1988 184.2 10.7 195.0 194.8 1989 139.9 62.1 202.1 202.6 1990 125.3 27.0 152.3 153.0 1991 102.5 18.6 121.0 121.2 1992 114.0 36.9 150.9 151.8 1993 121.7 21.9 143.6 174.0 1994 110.6 99.6 210.2 203.2 1995 136.1 32.2 168.3 223.2 1996 126.3 14.3 140.6 199.4 1997 124.2 33.6 157.8 173.4 1998 146.0 40.5 186.5 179.3 1999 96.2 14.2 110.4 138.5 2000 71.4 13.7 85.1 96.2 2001 49.7 13.9 63.6 75.9 2002 54.9 5.7 60.6 81.6 2003 30.9 6.4 37.2 76.7 2004 28.2 5.8 34.0 53.9 2005 28.7 6.3 35.0 51.9 2006 26.6 8.1 34.6 53.3 2007 24.4 23.6 48.1 70.1 2008 26.8 21.8 48.7 90.7 38 ICES Advice 2009, Book 6

Table 6.4.2.4 Cod in Subarea IV (North Sea), Division VIId (Eastern Channel), and Division IIIa (Skagerrak). Summary from stock assessment. Run title: North Sea/Skagerrak/Eastern Channel Cod Tuning data. INCLUDES DISCARDS 30/04/2009 10:26 B-ADAPT median values RECRUITS TSB SSB CATCH YIELD/SSB FBAR 2-4 Age 1 ('000) (tons) (tons) (tons) 1963 249718 443856 164821 128686 0.781 0.499 1964 462750 530389 166809 130740 0.784 0.477 1965 687286 695016 193421 210237 1.087 0.570 1966 835166 846628 225100 259416 1.152 0.581 1967 748976 900304 249059 276387 1.110 0.589 1968 329855 797607 254722 305911 1.201 0.704 1969 295479 654250 252744 205510 0.813 0.543 1970 1143743 993899 260553 243867 0.936 0.620 1971 1687701 1201678 264800 412264 1.557 0.781 1972 329293 863226 243532 387737 1.592 0.823 1973 561402 683266 205762 269139 1.308 0.797 1974 550554 650496 233150 253989 1.089 0.705 1975 1030925 728266 211890 242349 1.144 0.749 1976 769399 644409 180579 307102 1.701 0.948 1977 1898803 946599 163815 349038 2.131 0.837 1978 638410 817810 150864 328585 2.178 0.953 1979 1502822 964889 158450 430688 2.718 0.758 1980 2807522 1255362 179034 590678 3.299 0.873 1981 609627 844173 190515 393451 2.065 0.916 1982 983478 834918 184954 359372 1.943 1.009 1983 470856 638926 148887 281696 1.892 1.031 1984 1485856 825394 131990 379974 2.879 0.917 1985 272216 505132 124377 247031 1.986 0.918 1986 1668788 761628 115131 341047 2.962 0.957 1987 363026 563625 107496 244809 2.277 0.947 1988 238092 432243 98890 194798 1.970 0.992 1989 630938 469625 92913 202639 2.181 0.961 1990 199511 323769 81361 153021 1.881 0.973 1991 260092 301415 78090 121204 1.552 0.818 1992 546894 428548 77338 151755 1.962 0.776 1993 254721 372630 78810 173978 2.208 0.992 1994 939238 520934 75503 203158 2.691 0.718 1995 413639 531888 95546 223243 2.336 0.927 1996 233277 443080 103589 199412 1.925 0.986 1997 734266 537068 91120 173408 1.903 0.867 1998 96659 349928 76426 179324 2.346 0.995 1999 177838 256969 74317 138457 1.863 1.167 2000 299673 241222 49052 96179 1.961 1.074 2001 86372 182425 38830 75895 1.955 0.801 2002 155474 217959 47150 81559 1.730 0.790 2003 73605 152148 43644 76695 1.757 0.930 2004 106661 128590 40050 53925 1.346 0.903 2005 88393 132469 36564 51858 1.418 0.725 2006 218422 145291 34475 53268 1.545 0.694 2007 98279 189117 42313 70102 1.657 0.619 2008 120160 212026 57282 90687 1.583 0.788 2009 60139 ICES Advice 2009, Book 6 39

Annex 6.4.2 EU Norway management plan In 2008 the EU and Norway renewed their initial agreement from 2004 and agreed to implement a long-term management plan for the cod stock, which is consistent with the precautionary approach and is intended to provide for sustainable fisheries and high yield. Transitional arrangement: F will be reduced as follows: 75 % of F in 2008 for the TACs in 2009, 65 % of F in 2008 for the TACs in 2010, and applying successive decrements of 10 % for the following years. The transitional phase ends as from the first year in which the long-term management arrangement (paragraphs 3 5) leads to a higher TAC than the transitional arrangement. Long-term management 1. If the size of the stock on 1 January of the year prior to the year of application of the TACs is: a. Above the precautionary spawning biomass level, the TACs shall correspond to a fishing mortality rate of 0.4 on appropriate age groups; b. Between the minimum spawning biomass level and the precautionary spawning biomass level, the TACs shall not exceed a level corresponding to a fishing mortality rate on appropriate age groups equal to the following formula: 0.4 - (0.2 * (Precautionary spawning biomass level - spawning biomass) / (Precautionary spawning biomass level - minimum spawning biomass level)) c. At or below the limit spawning biomass level, the TAC shall not exceed a level corresponding to a fishing mortality rate of 0.2 on appropriate age groups. 2. Notwithstanding paragraphs 2 and 3, the TAC for 2010 and subsequent years shall not be set at a level that is more than 20 % below or above the TACs established in the previous year. 3. Where the stock has been exploited at a fishing mortality rate close to 0.4 during three successive years, the parameters of this plan shall be reviewed on the basis of advice from ICES in order to ensure exploitation at maximum sustainable yield. 4. The TAC shall be calculated by deducting the following quantities from the total removals of cod that are advised by ICES as corresponding to the fishing mortality rates consistent with the management plan: a. A quantity of fish equivalent to the expected discards of cod from the stock concerned; b. A quantity corresponding to other relevant sources of cod mortality. 5. The Parties agree to adopt values for the minimum spawning biomass level (70,000 tonnes), the precautionary biomass level (150,000 tonnes) and to review these quantities as appropriate in the light of ICES advice. Procedure for setting TACs in data-poor circumstances 6. If, due to a lack of sufficiently precise and representative information, it is not possible to implement the provisions in paragraphs 3 to 6, the TAC will be set according to the following procedure. a. If the scientific advice recommends that the catches of cod should be reduced to the lowest possible level the TAC shall be reduced by 25 % with respect to the TAC for the preceding year. b. In all other cases the TAC shall be reduced by 15 % with respect to the TAC for the previous year, unless the scientific advice recommends otherwise. This plan shall be subject to triennial review, the first of which will take place before 31 December 2011. It enters into force on 1 January 2009. The main changes between this and the plan of 2004 is the phasing (transitional and long-term phase) and the inclusion of an F reduction fraction, 40 ICES Advice 2009, Book 6

EU management plan In December 2008 the European Council agreed on a new cod management plan implementing the new system of effort management and a target fishing mortality of 0.4 (EC 1342/2008). The HCR for setting TAC for the North Sea cod stock are as follows: Article 7 1.(a) and 1.(b) are required for interpretation of Article 8. Article 7: Procedure for setting TACs for cod stocks in the Kattegat the west of Scotland and the Irish Sea 1. Each year, the Council shall decide on the TAC for the following year for each of the cod stocks in the Kattegat, the west of Scotland and the Irish Sea. The TAC shall be calculated by deducting the following quantities from the total removals of cod that are forecast by STECF as corresponding to the fishing mortality rates referred to in paragraphs 2 and 3: (a) a quantity of fish equivalent to the expected discards of cod from the stock concerned; (b) as appropriate a quantity corresponding to other sources of cod mortality caused by fishing to be fixed on the basis of a proposal from the Commission. [ ] Article 8: Procedure for setting TACs for the cod stock in the North Sea, the Skagerrak and the eastern Channel 1. Each year, the Council shall decide on the TACs for the cod stock in the North Sea, the Skagerrak and the eastern Channel. The TACs shall be calculated by applying the reduction rules set out in Article 7 paragraph 1(a) and (b). 2. The TACs shall initially be calculated in accordance with paragraphs 3 and 5. From the year where the TACs resulting from the application of paragraphs 3 and 5 would be lower than the TACs resulting from the application of paragraphs 4 and 5, the TACs shall be calculated according to the paragraphs 4 and 5. 3. Initially, the TACs shall not exceed a level corresponding to a fishing mortality which is a fraction of the estimate of fishing mortality on appropriate age groups in 2008 as follows: 75 % for the TACs in 2009, 65 % for the TACs in 2010, and applying successive decrements of 10 % for the following years. 4. Subsequently, if the size of the stock on 1 January of the year prior to the year of application of the TACs is: (a) above the precautionary spawning biomass level, the TACs shall correspond to a fishing mortality rate of 0,4 on appropriate age groups; (b) between the minimum spawning biomass level and the precautionary spawning biomass level, the TACs shall not exceed a level corresponding to a fishing mortality rate on appropriate age groups equal to the following formula: 0,4 (0,2 * (Precautionary spawning biomass level spawning biomass) / (Precautionary spawning biomass level minimum spawning biomass level)) (c) at or below the limit spawning biomass level, the TACs shall not exceed a level corresponding to a fishing mortality rate of 0,2 on appropriate age groups. 5. Notwithstanding paragraphs 3 and 4, the Council shall not set the TACs for 2010 and subsequent years at a level that is more than 20 % below or above the TACs established in the previous year. 6. Where the cod stock referred to in paragraph 1 has been exploited at a fishing mortality rate close to 0,4 during three successive years, the Commission shall evaluate the application of this Article and, where appropriate, propose relevant measures to amend it in order to ensure exploitation at maximum sustainable yield. Article 9: Procedure for setting TACs in poor data conditions Where, due to lack of sufficiently accurate and representative information, STECF is not able to give advice allowing the Council to set the TACs in accordance with Articles 7 or 8, the Council shall decide as follows: (a) where STECF advises that the catches of cod should be reduced to the lowest possible level, the TACs shall be set according to a 25 % reduction compared to the TAC in the previous year; (b) in all other cases the TACs shall be set according to a 15 % reduction compared to the TAC in the previous year, unless STECF advises that this is not appropriate. Article 10: Adaptation of measures 1. When the target fishing mortality rate in Article 5(2) has been reached or in the event that STECF advises that this target, or the minimum and precautionary spawning biomass levels in Article 6 or the levels of fishing mortality rates given in Article 7(2) are no longer appropriate in order to maintain a low risk of stock depletion and a maximum sustainable yield, the Council shall decide on new values for these levels. ICES Advice 2009, Book 6 41

2. In the event that STECF advises that any of the cod stocks is failing to recover properly, the Council shall take a decision which: (a) sets the TAC for the relevant stock at a level lower than that provided for in Articles 7, 8 and 9; (b) sets the maximum allowable fishing effort at a level lower than that provided for in Article 12; (c) establishes associated conditions as appropriate. 42 ICES Advice 2009, Book 6

6.4.3 Haddock in Subarea IV (North Sea) and Division IIIa West (Skagerrak) Corrected November 2009 State of the stock Spawning biomass in relation to precautionary limits Full reproductive capacity Fishing mortality in relation to precautionary limits Fishing mortality in relation to high long-term yield Fishing mortality in relation to management target Harvested sustainably Appropriate Below target Comment Based on the most recent estimate of SSB (in 2009) and fishing mortality (in 2008), ICES classifies the stock as having full reproductive capacity and being harvested sustainably. SSB in 2009 is estimated to be above B pa, although SSB has been declining since 2002. Fishing mortality in 2008 is estimated to be below F pa, and below the target F HCR (0.3) specified in the EU Norway management plan. Recruitment is characterized by occasional large yield classes, the last of which was the strong 1999 year class. Apart from the 2005 year class which is about average, recent recruitment has been poor. Management objectives In 1999 the EU and Norway agreed to implement a long-term management plan for the haddock stock, which is consistent with the precautionary approach and which is intended to constrain harvesting within safe biological limits (SSB > B lim ) and is designed to provide for sustainable fisheries and high potential yield (F HCR = 0.3). A revised management plan was implemented in January 2009 (Annex 6.4.3). The main elements of the plan are a target F of 0.3 with a limit of 15% change in TAC provided SSB is maintained above 140 000 t. If SSB is between 140 000 t and 100 000 t, F is reduced in line with SSB to reach F = 0.1 at SSB=100 000 t. If SSB is at 100 000 t or below, F is 0.1. Interannual quota flexibility is permitted, with a maximum of ±10% transfer of quota between years. ICES has evaluated this EU Norway management plan and concluded that the target F HCR = 0.3 with TAC constraint ±15% leads on average to a <5% risk of B < B lim within the next 20 years. Increasing the target F HCR increases the risk. Although the management plan has not been fully tested (e.g. at lower fishing mortalities), ICES concludes that the management plan can provisionally be accepted as precautionary and be used as the basis for advice. Interannual quota flexibility has also been evaluated and it is concluded that this has no significant impact on sustainability. Reference points Precautionary approach Type Value Technical basis B lim 100 000 t Smoothed B loss. B pa 140 000 t B pa = 1.4 * B lim. F lim 1.0 F lim = 1.4 * F pa. F pa 0.7 10% probability that SSB MT < B pa. Targets F HCR 0.3 Based on HCR simulations and agreed in the management plan (unchanged since 2007) Yield and spawning biomass per Recruit F-reference points Yield-per-recruit and SSB-per-recruit analyses are unstable between recent years due to variation in the selection pattern; therefore, no values are presented here. An HCR evaluation has shown that candidates for reference points consistent with high long-term yields and a low risk of depleting the productive potential of the stock can be found at F = 0.3. ICES Advice 2009, Book 6 43

Single-stock exploitation boundaries * Considering the options below, ICES advises on the basis of the management plan that implies landings in 2010 of 38 000 t, including industrial bycatch. Exploitation boundaries in relation to existing management plans Following the agreed management plan implies landings in 2010 of 38 000 t, which is expected to lead to an SSB of 185 000 t in 2011. The constraint on interannual TAC variability (±15%) is invoked in this case: the suggested 2010 landings represent a 15% decrease from the 2009 quota. The management plan can be provisionally accepted as precautionary. Exploitation boundaries in relation to high long-term yield, low risk of depletion of production potential, and considering ecosystem effects The current fishing mortality is estimated at 0.23, which is below the target rate expected to lead to high long-term yields (F = 0.3). Exploitation boundaries in relation to precautionary reference points Catches of 93 000 t implying landings of less than 76 000 t in 2010 would reduce SSB in 2011 to B pa corresponding to a threefold increase of fishing mortality. * Corrections made in November are presented in bold. 44 ICES Advice 2009, Book 6

ICES Advice 2009, Book 6 45 Short-term implications Outlook for 2010 Basis: F(2009) = TAC constraint = 0.23; SSB (2010) = 204; HC landings (2009) = 45; Discards (2009) = 8; Industrial bycatch (2009) = 0.2 Rationale Human consumption Basis F (2010) F HC (2010) F disc (2010) F ind. Bycatch Discards Ind. Bycatch Catch (2010) SSB (2011) %SSB change 1) %TAC change 2) (2010) (2010) (2010) (2010) Zero catch 0 F = 0 0.00 0.00 0.00 0.001 0 0 0 230 13% -100% Status quo 30 Fsq 0.25 0.16 0.09 0.001 6 0 37 194-5% -33% Target reference point 35 F(target) (Fsq*1.19) 0.30 0.19 0.11 0.001 8 0 43 188-8% -21% Agreed management plan 38 Management plan (15% quota cut) 0.33 0.20 0.12 0.001 8 0 46 185-9% -15% (Fsq *1.3) High long-term yield 49 F0.1 (Fsq*1.79) 0.44 0.27 0.16 0.001 11 0 60 171-16% 10% 9 Fsq * 0.28 0.07 0.04 0.03 0.001 2 0 11 219 8% -80% 22 Fsq * 0.70 0.18 0.11 0.07 0.001 5 0 26 204 0% -52% 40 Fsq * 1.39 0.35 0.22 0.13 0.001 9 0 49 182-11% -10% 55 Fsq * 2 0.50 0.31 0.19 0.001 12 0 67 165-19% 23% Status quo 57 Fsq * 2.09 0.52 0.33 0.20 0.001 12 0 70 162-21% 28% 66 Fsq * 2.51 0.63 0.39 0.24 0.001 14 0 81 151-26% 48% 72 Fpa (Fsq * 2.8) 0.70 0.44 0.26 0.001 16 0 88 145-29% 61% 76 Bpa (Fsq * 3.0) 0.75 0.47 0.28 0.001 17 0 93 140-31% 70% 77 Fsq * 3.06 0.77 0.48 0.29 0.001 17 0 94 139-32% 72% 85 Fsq * 3.48 0.87 0.54 0.33 0.001 19 0 104 130-36% 89% Units: 000 tonnes. Shaded scenarios are not considered consistent with the precautionary approach. Under the assumption that effort is linearly related to fishing mortality 1) SSB 2011 relative to SSB 2010. 2) Human Consumption 2010 relative to TAC 2009 The landings in Division IIIa are calculated as 6% of the combined area total. The figure 6% has been used as the basis of the TAC split for the past 3 years Corrections made in November are presented in bold. ICES Advice 2009, Book 6 45

Management considerations Adherence to the EU Norway management plan has contributed to lower fishing mortality levels, increased yield and greatly improved stability of yield. As the 2005 year class entered the fishery, discards were fairly substantial in 2006 and 2007, although they were considerably lower in 2008. Further improvements to gear selectivity measures, allowing for the release of small fish, would be highly beneficial not only for the haddock stock, but also for the survival of juveniles of other species that occur in mixed fisheries along with haddock. Haddock is a specific target for some fleets, but is also caught as part of a mixed fishery catching cod, whiting and Nephrops. For management to be effective, both species-specific assessments and the latest developments in mixed fisheries approaches need to be considered. A reduction in direct effort on one stock may lead to a reduction or an increase in effort on another and, hence, the implications of any changes need to be identified and carefully evaluated. Estimates of haddock bycatch in the industrial fishery are provided in the catch option table. These are low values based on the assumption of a similar bycatch rate to that observed in previous years, when the industrial fisheries were at a low level. A larger catch allocation for bycatch may be required if industrial effort increases (see Norway pout advice section 6.4.20). The advice for this stock is given for Subarea IV (North Sea) and Division IIIaN (Skagerrak), while the TACs for this stock are set for Division IIa and Subarea IV, and the whole of Subarea III, respectively. ICES has developed a generic approach to evaluate whether new survey information that becomes available in September forms a basis to update the advice. If this is the case, ICES will publish new advice in November 2009. Management plan evaluations The evaluations of the management plan that were carried out during 2007 used a recruitment model which is thought to capture the sporadic nature of haddock recruitment. On this basis, a target F = 0.3 with TAC constraint ±15% leads to a low risk of <12% in any year, and a mean risk of 5% over all years of B < B lim over the next 20 years. Lower Fs lead to lower risks. Interannual quota flexibility has also been evaluated and it is concluded that this has no significant impact on sustainability. Although the management plan has not been fully tested (e.g. the effect of the new rule for low biomass is not well known), ICES concludes that the management plan can be provisionally accepted as precautionary and can be used as the basis for advice. Factors affecting the fisheries and the stock Regulation and their effects EU technical regulations in force are contained in Council Regulation (EC) 850/98 and its amendments. The regulation prescribes the minimum target species composition for different mesh size ranges. In 2001, haddock in the whole of NEAFC region 2 were a legitimate target species for towed gears with a minimum codend mesh size of 100 mm. As part of the cod recovery measures, the EU and Norway introduced additional technical measures from 1 January 2002 (EC 2056/2001). The basic minimum mesh size for towed gears for cod from 2002 was 120 mm, although in a transitional arrangement running until 31 December 2002 vessels were allowed to exploit cod with 110 mm codends, provided that the trawl was fitted with a 90 mm square-mesh panel and the catch composition of cod retained on-board was not greater than 30% by weight of the total catch. From 1 January 2003, the basic minimum mesh size for towed gears for cod was 120 mm. The minimum mesh size for vessels targeting haddock in Norwegian waters is also 120 mm. The effect of the measures has been to reduce fishing mortality on haddock to sustainable levels and to maintain the spawning biomass above B pa despite a prolonged series of poor recruitments. Effort restrictions in the EC were introduced in 2003 (annual annexes to the TAC regulations) for the protection of the North Sea (?) cod stock. In 2009, the management program switched from a days at sea to a kw/day system (2009 Council Regulation (EC) N 43/2009), in which different amounts of kw/days are allocated within each area by Member State to different groups of vessels depending on gear and mesh size. In 2008, STECF indicated that overall effort (kw/days) by demersal trawls, seines and beam trawls had been substantially reduced since 2002. Fishing mortality declined between 2003 and 2007 concomitant with this effort reduction, but F increased again in 2008 despite a further nominal reduction in effort. Marked changes have also occurred in the use of the different mesh size categories by demersal trawlers. A sharp reduction has occurred in the use of mesh sizes between 100mm and 119mm, while a 46 ICES Advice 2009, Book 6

pronounced increase is apparent in the use of mesh sizes of 120mm and greater. As well, a general increase in effort has been observed in vessels using mesh sizes of 70-89mm and 90-99mm. Scotland implemented in February 2008 a national scheme known as the Conservation Credits Scheme. The principle of this two-part scheme involves additional time at sea in return for the adoption of measures which aims to reduce mortality on cod and lead to a reduction in discard numbers. ICES has not yet been able to evaluate the consequences of these measures. Despite their introduction, ICES notes that during the initial year of operation (2008) cod discarding rates increased substantially. Changes in fishing technology and fishing patterns The change in mesh size (to 120 mm) might be expected to shift exploitation patterns to older ages and increase the weight-at-age for retained fish from younger age classes. While reduced exploitation on more abundant cohorts can be seen, overall improvements in the exploitation pattern have not been observed. It was not possible to determine if this is due to confounding effects from other fleet segments. The effort in the UK large-mesh demersal trawl fleet category (>100 mm, 4A) has been reduced by decommissioning and days-at-sea regulations to 40% of the levels recorded in the EU reference year of 2001. There was a movement of effort into the 70 90 mm sector to increase days-at-sea in 2002 and 2003, but the level of effort in this sector stabilized in 2004. Scientific basis Data and methods The age-based assessment model (XSA) is calibrated with three survey indices. Discards and industrial bycatch data were included in the assessment. Discards were estimated from the discards sampling programme from several countries, with most observations coming from Scotland. The samples were then raised to the total international fleet. Information from the fishing industry The report of the North Sea Fishers Survey (Laurenson 2008) shows that the industry perception of haddock abundance in the main haddock fishing areas (1 and 2) is of stabilization, which concurs with the indications from the assessment of a temporary slowing of the rate of decline in SSB with the growth of the 2005 year class. The previous decline in haddock abundance estimated by the assessment is not apparent in the Survey. This suggests that demersal vessels may be able to maintain good catch rates of haddock in spite of declining abundance. Uncertainties in assessment and forecast The trends indicated by the assessment are in agreement with the surveys. The assessment and forecast are largely influenced by the moderate 2005 year class. Comparison with previous assessment and advice The basis of the assessment and advice is the same as last year. The assessment is sensitive to the estimation of a few large cohorts, so the variability in estimates among assessment years is to be expected. There are no indications of assessment bias. Source of information Report of the Working Group on the Assessment of Demersal Stocks in the North Sea and Skagerrak, 6-12 May 2009 (ICES CM 2009/ACOM:10). STECF PLEN-08-03 EUR 23624 EN, ISBN 978-79-10940-9, ISSN 1018-5593, DOI 10.2788/3484, 2008 ICES Advice 2009, Book 6 47

Table 6.4.3.1 Haddock in Subarea IV (North Sea) Single stock exploitation boundaries (advice), management and catch. ICES catches Year ICES Single-stock Predicted Predicted landings Agreed Off. Hum. Disc Indust. Total Advice exploitation boundaries landings corresp. to advice 1 corresp. to singlestock exploitation boundaries 2 TAC lndgs. Cons. Slip. bycatch 1987 80% of F(85) 105 140 109 108 59 4 172 1988 77% of F(86); 185 185 105 105 62 4 171 TAC 1989 Reduce decline in 68 68 64 76 26 2 104 SSB; TAC; protect juveniles 1990 80% of F(88); 50 50 43 51 33 3 87 TAC 1991 70% of effort (89) 50 45 45 40 5 90 1992 70% of effort (89) 60 51 70 48 11 129 1993 70% of effort (89) 133 80 80 80 11 170 1994 Significant 160 87 81 65 4 150 reduction in effort; mixed fishery 1995 Significant 120 75 75 57 8 140 reduction in effort; mixed fishery 1996 Mixed fishery to 120 75 76 73 5 154 be taken into account 1997 Mixed fishery to 114 73 79 52 7 138 be taken into account 1998 No increase in F 100.3 115 72 77 45 5 128 1999 Reduction of 10% 72 88.6 64 64 43 4 111 F(95 97) 2000 F less than F pa <51.7 73.0 47 45 47 8 100 2001 F less than F pa <58.0 61 40 39 118 8 165 2002 F less than F pa <94.0 104.0 54 53 45 4 101 2003 No cod catches - 52 42 42 23 1 76 2004 Mixed fisheries F should be * No forecast 85 47 47 17 1 65 consideration below F pa 2005 Mixed fisheries F should be * 92 66 47 48 10 0 57 consideration below F pa 2006 Mixed fisheries F should be * 39 52 36 36 17 0 55 consideration below 0.3 2007 Mixed fisheries F should be * 55.4 55 30 31 30 0 61 consideration below 0.3 2008 Mixed fisheries 15% TAC * 49.3 3 46 30 29 13 0 42 consideration reduction TA 2009 Mixed fisheries consideration Apply management * 44.7 3 42 2010 Mixed fisheries consideration plan Apply management plan * 38 3 Weights in 000 t. 1 Only pertaining to the North Sea. 2 For the whole stock (Division IIIaN and Subarea IV). 3 Including industrial bycatch. * Single-stock boundary and the exploitation of this stock should be conducted in the context of mixed fisheries protecting stocks outside safe biological limits. 48 ICES Advice 2009, Book 6

Table 6.4.3.1 Haddock in Division IIIaW (Skagerrak) Single stock exploitation boundaries (advice), management and landings. Year ICES Advice Single-stock exploitation boundaries Predicted landings corresp. to advice Predicted landings corresp to singlestock exploitation boundaries Agreed TAC ICES landings Hum. Indust. Total Cons. bycatch 1987 Precautionary TAC - 11.5 3.8 1.4 5.3 1988 Precautionary TAC - 10.0 2.9 1.5 4.3 1989 Precautionary TAC - 10.0 4.1 0.4 4.5 1990 Precautionary TAC - 10.0 4.1 2.0 6.1 1991 Precautionary TAC 4.6 4.6 4.1 2.6 6.7 1992 TAC 4.6 4.6 4.4 4.6 9.0 1993 Precautionary TAC - 4.6 2.0 2.4 4.4 1994 Precautionary TAC - 10.0 1.8 2.2 4.0 1995 If required, precautionary TAC; link to North Sea 1996 If required, precautionary TAC; link to North Sea 1997 Combined advice with North Sea 1998 Combined advice with North Sea 1999 Combined advice with North Sea 2000 Combined advice with North Sea 2001 Combined advice with North Sea 2002 Combined advice with North Sea 2003 Combined advice with North Sea 2004 Combined advice with North Sea 2005 Combined advice with North Sea 2006 Combined advice with North Sea 2007 Combined advice with North Sea 2008 Combined advice with North Sea 2009 Combined advice with North Sea 2010 Combined advice with North Sea Weights in 000 t. n/a = not available. F should be below F pa F should be below F pa F should be below 0.3 F should be below 0.3 15% TAC reduction Apply management plan Apply management plan - 10.0 2.2 2.2 4.4-10.0 3.1 2.9 6.1-7.0 3.4 0.6 4.0 4.7 7.0 3.8 0.3 4.0 3.4 5.4 1.4 0.3 1.7 <1.8 4.5 1.5 0.6 2.1 <2.0 4.0 1.9 0.2 2.1 <3.0 6.3 4.1 0.06 4.1-3.2 1.8 n/a 1.8 No forecast 4.9 1.4 n/a 1.4-4.0 0.8 0 0.8-3.2 1.5 0 1.5-3.4 1.6 0 2.5 2.9 2.9 1.4 0 2.0-2.6 - ICES Advice 2009, Book 6 49

Figure 6.4.3.1. Haddock in Subarea IV (North Sea) and Division IIIaW (Skagerrak). Summary plots. The dotted horizontal lines indicate F pa (top right plot) and B pa (bottom left plot), while the solid ones indicate F lim (top right plot) and B lim (bottom left plot). Stock - Recruitment Recruitment (age 0) in billions 450 400 350 300 250 200 150 100 50 0 0 200 400 600 800 1000 SSB-Rec. Blim Bpa SSB in 1000 t Figure 6.4.3.2. Haddock in Subarea IV (North Sea) and Division IIIaW (Skagerrak). Stock recruitment plot. 50 ICES Advice 2009, Book 6

Figure 6.3.3.3. Haddock in Subarea IV (North Sea) and Division IIIaW (Skagerrak). Results of 2008 North Sea Stock Survey. Each plot presents a summary of the responses by North Sea roundfish reporting area. Haddock in Subarea IV (North Sea) and Division IIIa West (Skagerrak) 600 SSB ('000 tonnes) 1.40 Fishing mortality: 2-4 160 Billions Recruitment. Age: 0 500 1.20 140 400 1.00 0.80 120 100 300 80 0.60 200 0.40 60 40 100 0.20 20 0 1990 1995 2000 2005 0.00 1990 1995 2000 2005 0 1990 1995 2000 2005 Figure 6.4.3.3 Haddock in Subarea IV (North Sea) and Division IIIaW (Skagerrak). Comparison of current assessment with previous assessments. ICES Advice 2009, Book 6 51

Table 6.4.3.3 Haddock in Subarea IV (North Sea) and Division IIIaW (Skagerrak). Catches/landings by country and area. Sum of Landings Year ICES area Country 2001 2002 2003 2004 2005 2006 2007 2008 2009 Division IIIa Belgium 0 0 0 0 0 0 0 Denmark 1590 3791 1741 1116 615 1001 1054 1053 Faeroe Islands 0 0 0 0 0 0 0 Germany 128 239 113 69 69 186 206 87 Netherlands 0 0 6 1 0 0 0 Norway 149 149 211 154 93 113 152 170 Portugal 0 0 0 0 0 30 37 Sweden 283 393 165 158 180 246 278 274 UK - Eng+Wales+N.Irl. 0 0 0 0 0 0 0 UK - Scotland 7 0 0 0 0 0 0 Division IIIa Total 2157 4572 2236 1498 957 1576 1727 1584 WG Division IIIa WG estimates of discards 0 0 195 112 217 970 816 646 WG estimates of IBC 0 0 0 0 0 0 0 0 WG estimates of landings 1903 4137 1808 1443 764 1537 1515 1374 WG estimates of total catch 1903 4137 2003 1555 981 2507 2332 2020 WG Division IIIa Total 3806 8273 4007 3110 1963 5014 4663 4041 Subarea IV Belgium 606 559 374 373 190 105 179 112 Denmark 2407 5123 3035 2075 1274 759 645 501 Faeroe Islands 1 25 12 22 22 4 0 3 France 485 914 1108 552 439 444 498 302 Germany 681 852 1562 1241 733 725 727 393 Greenland 0 0 149 686 18 5 0 Ireland 0 0 1 0 0 0 0 Netherlands 274 359 187 104 64 33 55 29 Norway 1902 2404 2196 2258 2089 1798 1706 1478 Poland 12 17 16 0 0 8 8 16 Portugal 0 0 0 0 0 76 0 Sweden 804 572 477 188 135 100 130 85 UK - Eng+Wales+N.Irl. 3334 3647 1561 1159 651 477 1799 UK - Scotland 29263 39624 31527 39339 25319 31905 24919 UK - all 27341 Subarea IV Total 39769 54096 42205 47997 30934 36439 30666 30260 WG Subarea IV WG estimates of discards 118320 45892 23499 15439 8416 16943 27805 12532 WG estimates of IBC 7879 3717 1150 554 168 535 48 199 WG estimates of landings 38958 54171 40140 47253 47616 36074 29418 28893 WG estimates of total catch 167060 107917 66792 64800 57181 56058 59603 43644 WG Subarea IV Total 332217 211697 131580 128046 113380 109610 116874 85268 TAC TAC IIIa 4000 6300 3150 4940 4018 3189 3360 2856 2590 TAC IV 61000 104000 51735 77000 66000 51850 54640 46444 42110 TAC Total 65000 110300 54885 81940 70018 55039 58000 49300 44700 52 ICES Advice 2009, Book 6

Table 6.4.3.4 Haddock in Subarea IV (North Sea) and Division IIIaW (Skagerrak). Summary of stock assessment. RECRUITMENT TSB SSB CATCH LANDINGS DISCARDS IBC YIELD/SSB MEAN F(2-4) 1963 2315029 3412701 137055 271851 68821 189329 13700 0.502 0.745 1964 9155436 1281826 417718 379915 131006 160309 88600 0.314 0.794 1965 26286793 1081002 521742 299344 162418 62326 74600 0.311 0.639 1966 68923260 1480501 427843 346349 226184 73465 46700 0.529 0.662 1967 388351571 5527477 224795 246664 147742 78222 20700 0.657 0.626 1968 17114876 6852043 259402 301821 105811 161810 34200 0.408 0.597 1969 12133821 2477692 810551 930043 331625 260065 338353 0.409 1.121 1970 87606750 2541782 900223 805776 524773 101274 179729 0.583 1.152 1971 78211007 2546502 420405 446824 237502 177776 31546 0.565 0.773 1972 21426954 2182328 302982 353084 195545 127954 29585 0.645 1.119 1973 72953038 4088546 297169 307595 181592 114736 11267 0.611 0.866 1974 132869060 4711585 260797 366992 153057 166429 47505 0.587 0.962 1975 11407700 2385624 238364 453205 151349 260369 41487 0.635 1.101 1976 16402039 1097845 309660 375305 172680 154462 48163 0.558 0.972 1977 26219907 1069750 242563 224516 145118 44376 35022 0.598 1.031 1978 39832982 1138494 138416 179376 91683 76789 10903 0.662 1.06 1979 72661935 1353240 117454 145020 87069 41710 16240 0.741 0.985 1980 15806947 1472212 169873 222126 105041 94614 22472 0.618 0.896 1981 32617680 997530 257894 213240 136132 60067 17041 0.528 0.656 1982 20491370 1092906 321698 233283 173335 40564 19383 0.539 0.657 1983 66956253 2254533 277335 244212 165337 65977 12898 0.596 0.882 1984 17181331 1692122 224959 218946 133568 75298 10080 0.594 0.871 1985 23920805 1189276 262039 255366 164119 85249 5998 0.626 0.871 1986 49030758 1942695 237914 223081 168236 52202 2643 0.707 1.201 1987 4156240 1098211 167460 173852 110299 59143 4410 0.659 1.022 1988 8339335 630796 160326 173123 106973 62148 4002 0.667 1.106 1989 8606296 623884 128027 106529 78439 25680 2410 0.613 0.949 1990 28351635 1582939 81017 88934 53780 32565 2589 0.664 1.111 1991 27479298 1553319 63345 93286 47715 40185 5386 0.753 0.886 1992 41947282 1364802 103501 131650 72790 47934 10927 0.703 0.978 1993 13157783 1019411 139012 172550 82176 79608 10766 0.591 0.894 1994 56144741 1488820 161684 151020 82074 65370 3576 0.508 0.826 1995 14447705 1174840 163135 142524 77458 57372 7695 0.475 0.729 1996 21503804 1063289 202515 156609 79148 72461 5000 0.391 0.685 1997 12826240 980803 227379 141347 82574 52089 6684 0.363 0.531 1998 9970725 796184 205012 131316 81054 45160 5101 0.395 0.596 1999 135516779 3608494 159117 112021 65588 42598 3835 0.412 0.702 2000 26511570 3515647 137513 104457 47553 48770 8134 0.346 0.754 2001 2835366 1224874 314654 166960 40856 118225 7879 0.13 0.488 2002 3750722 885642 517532 107922 58348 45857 3717 0.113 0.23 2003 3891493 767729 505527 66806 41964 23692 1150 0.083 0.203 2004 3731671 765036 433795 64839 48734 15551 554 0.112 0.263 2005 38595613 2620075 374772 57162 48357 8637 168 0.129 0.309 2006 7205011 1266096 298800 56056 37613 17908 535 0.126 0.508 2007 4572803 688998 214574 59643 30939 28657 48 0.144 0.405 2008 3735922 532933 203254 43640 30248 13194 199 0.149 0.251 2009 4067014 229325 3 Units Thousands Tonnes Tonnes Tonnes Tonnes Tonnes Tonnes 3 Corrections made in November are presented in bold. The relating figures have not been updated from the June advice. ICES Advice 2009, Book 6 53

Annex 6.4.3a EU and Norway Management plan The plan shall consist of the following elements: 1. Every effort shall be made to maintain a minimum level of Spawning Stock Biomass greater than 100,000 tonnes (B lim ). 2. For 2009 and subsequent years the Parties agreed to restrict their fishing on the basis of a TAC consistent with a fishing mortality rate of no more than 0.3 for appropriate age-groups, when the SSB in the end of the year in which the TAC is applied is estimated above 140,000 tonnes (B pa ). 3. Where the rule in paragraph 2 would lead to a TAC, which deviates by more than 15 % from the TAC of the preceding year, the Parties shall establish a TAC that is no more than 15 % greater or 15 % less than the TAC of the preceding year. 4. Where the SSB referred to in paragraph 2 is estimated to be below B pa but above B lim the TAC shall not exceed a level which will result in a fishing mortality rate equal to 0.3-0.2*(B pa -SSB)/(Bpa-Blim). This consideration overrides paragraph 3. 5. Where the SSB referred to in paragraph 2 is estimated to be below Blim the TAC shall be set at a level corresponding to a total fishing mortality rate of no more than 0.1. This consideration overrides paragraph 3. 6. In the event that ICES advises that changes are required to the precautionary reference points B pa (140,000t) or B lim, (100,000t) the Parties shall meet to review paragraphs 1-5. 7. In order to reduce discarding and to increase the spawning stock biomass and the yield of haddock, the Parties agreed that the exploitation pattern shall, while recalling that other demersal species are harvested in these fisheries, be improved in the light of new scientific advice from inter alia ICES. 8. No later than 31 December 2010, the parties shall review the arrangements in paragraphs 1 to 7 in order to ensure that they are consistent with the objective of the plan. This review shall be conducted after obtaining inter alia advice from ICES concerning the performance of the plan in relation to its objective. 9. This arrangement enters into force on 1 January 2009. 54 ICES Advice 2009, Book 6

6.4.4 Whiting in Division IIIa (Skagerrak Kattegat) Single-stock exploitation boundaries The landing data available for this stock give insufficient reason to change the advice from 2008. The advice on this stock for the fishery in 2010 is therefore the same as the advice given in 2008 for the 2009 fishery: The landings should be less than the average (2003 2005) landings of 1050 t as a precautionary value to restrict the potential for significant reexpansion of the fishery and misreporting from other regions. This advice will be updated in 2010. Source of information Report of the Working Group on the Assessment of Demersal Stocks in the North Sea and Skagerrak, 6-12 May 2009 ICES CM 2009/ACOM:10. Year ICES Advice / Single-Stock Exploitation Boundaries 2) Predicted catch corresp. to advice Predicted catch corresp. to Single- Stock Exploitation Boundaries Agreed TAC ICES Catch 1) 1987 Precautionary TAC - 17.0 16.7 1988 Precautionary TAC - 17.0 11.8 1989 Precautionary TAC - 17.0 13.3 1990 Precautionary TAC - 17.0 19.5 1991 TAC - 17.0 16.0 1992 No advice - 17.0 12.3 1993 Precautionary TAC - 17.0 6.6 1994 If required, precautionary TAC - 17.0 6.0 1995 If required, precautionary TAC - 15.2 9.7 1996 If required, precautionary TAC - 15.2 2.9 1997 If required, TAC equal to recent catches - 15.2 1.1 1998 No advice 15.2 1.0 1999 TAC, average period 1993 1996 6.0 8.0 1.4 2000 TAC, average period 1996 1998 1.5 4.0 1.4 2001 TAC, average period 1996 1998 1.5 2.5 1.8 2002 TAC, average period 1996 1998 1.5 2.0 1.7 2003 TAC, average period 1996 1998 1.5 1.5 0.8 2004 TAC, average period 1996 1998 1.5 1.5 1.3 2005 average period 1996 1998 2) 1.5 1.5 1.0 2006 average period 1996 1998 2) 1.5 1.5 0.4 2007 average period 1996 1998 2) 1.5 1.5 0.4 2008 Recent average catches 2) 1.050 1.050 0.4 2009 Same advice as last year 2) 1.050 1.050 2010 Same advice as last year 2) 1.050 Weights in 000 t. 1) Includes bycatch in small-mesh industrial fishery. 2) Single-stock boundary, and the exploitation of this stock should be conducted in the context of mixed fisheries protecting stocks outside safe biological limits. ICES Advice 2009, Book 6 55

Table 6.4.4.1 Whiting in Division IIIa. Nominal landings (t) by country as supplied by the Working Group. Year Denmark (1) Norway Sweden Others Total 1975 19,018 57 611 4 19,690 1976 17,870 48 1,002 48 18,968 1977 18,116 46 975 41 19,178 1978 48,102 58 899 32 49,091 1979 16,971 63 1,033 16 18,083 1980 21,070 65 1,516 3 22,654 Total consumption Total industrial Total 1981 1,027 23,915 24,942 70 1,054 7 26,073 1982 1,183 39,758 40,941 40 670 13 41,664 1983 1,311 23,505 24,816 48 1,061 8 25,933 1984 1,036 12,102 13,138 51 1,168 60 14,417 1985 557 11,967 12,524 45 654 2 13,225 1986 484 11,979 12,463 64 477 1 13,005 1987 443 15,880 16,323 29 262 43 16,657 1988 391 10,872 11,263 42 435 24 11,764 1989 917 11,662 12,579 29 675-13,283 1990 1,016 17,829 18,845 49 456 73 19,423 1991 871 12,463 13,334 56 527 97 14,041 1992 555 3,340 3,895 66 959 1 4,921 1993 261 1,987 2,248 42 756 1 3,047 1994 174 1,900 2,074 21 440 1 2,536 1995 85 2,549 2,634 24 431 1 3,090 1996 55 1,235 1,290 21 182-1,493 1997 38 264 302 18 94-414 1998 35 354 389 16 81-486 1999 37 695 732 15 111-858 2000 59 777 836 17 138 1 992 2001 61 970 1 1,031 1 27 126 + 1,184 1 2002 101 975 1 1,076 1 23 127 1 1,227 1 2003 93 654 1 747 1 20 71 2 840 1 2004 93 1,120 1 1,213 1 17 74 1 1,305 1 2005 49 907 1 956 1 13 73 0 1,042 1 2006 59 1 290 1 349 1 n/a n/a n/a 349 1 2007 54 227 281 14 82 1 378 2008 52 286 338 14 52 n/a 404 1 Values from 1992 updated by WGNSSK (2007) 56 ICES Advice 2009, Book 6

6.4.5 Whiting in Subarea IV (North Sea) and Division VIId (Eastern Channel) Corrected November 2009 State of the stock Spawning biomass in relation to precautionary limits Fishing mortality in relation to precautionary limits Fishing mortality in relation to high longterm yield Undefined Undefined Undefined NA Fishing mortality in relation to agreed target Comments In the absence of defined reference points, the state of the stock cannot be evaluated. An analytical assessment estimates SSB in 2009 as being near the lowest level since the beginning of the time-series in 1990. Fishing mortality has declined from 2000-2004, but increased in recent years. Recruitment has been very low since 2002, with an indication of a modest improvment in the 2007 year class. Management objectives There are no explicit management objectives for this stock. Reference points No precautionary reference points are set for this stock. Yield and spawning biomass per Recruit F-reference points (2009): Fish Mort Yield/R SSB/R Ages 2-6 Average last 3 years 0.41 0.02 0.07 Fmax N/A F0.1 * 0.57 0.01 0.06 Fmed N/A F 0.1 was revised in this year s assessment; further work is being conducted on the interpretation of F 0.1 for this stock. Candidates reference points consistent with high long-term yields and a low risk of depleting the productive potential of the stock cannot be recommended since fishing near F 0.1 = 0.57 in the past was accompanied with marked declines in the stock. Single-stock exploitation boundaries * Because no reference points are available, ICES advises on the basis of precautionary considerations that a significant reduction of the TAC is required to remedy the decline in SSB. An immediate TAC reduction of 64 % (12 500 t Total catch, 6 800 t human consumption catch) is needed to stabilize the stock, but rebuilding would require a further reduction. * Corrections made in November are presented in bold. ICES Advice 2009, Book 6 57

Short-term implications Outlook for 2010 Basis: F (2009) = Mean F (2006 2008) scaled to F (2008) = 0.47; R(2009) = RCT3 = 1297; SSB (2009) = 94; SSB (2010) = 89; landings (2009) = 19; discards (2009) = 11. HC Total F F F F Disc. Ind. % TAC SSB %SSB Rationale Catch Catch Basis Total HC Disc. Ind. Catch Catch 2011 change 1) change 2) 2010 2010 2010 2010 2010 2010 2010 2010 Zero -100% 0.0 1.9 0 0.02 0.00 0.00 0.02 0.0 1.9 102.5 10% catch 2.1 5.2 0.1*Fsq 0.07 0.03 0.01 0.02 1.2 1.9 99.7 7% -89% Status -78% 4.2 8.4 0.2*Fsq 0.11 0.06 0.03 0.02 2.3 1.9 97.0 4% quo 6.1 11.4 0.3*Fsq 0.16 0.09 0.04 0.02 3.4 1.9 94.4 1% -68% 6.8 12.5 0.33*Fsq 0.17 0.10 0.05 0.02 3.8 1.9 93.6 0% -64% 9.9 17.3 0.5*Fsq 0.24 0.15 0.07 0.02 5.5 1.8 89.6-4% -48% 11.7 20.0 0.6*Fsq 0.29 0.19 0.08 0.02 6.5 1.8 87.3-7% -38% 13.4 22.7 0.7*Fsq 0.33 0.22 0.10 0.02 7.5 1.8 85.1-9% -29% 15.1 25.3 0.8*Fsq 0.38 0.25 0.11 0.02 8.5 1.7 82.9-11% -20% 16.1 26.9 0.86*Fsq 0.41 0.27 0.12 0.02 9.0 1.7 81.6-13% -15% 18.3 30.2 Fsq 0.47 0.31 0.14 0.02 10.3 1.7 78.9-16% -4% 19.8 32.6 1.1*Fsq 0.51 0.34 0.15 0.02 11.1 1.7 77.0-18% 4% 21.3 34.9 1.2*Fsq 0.56 0.37 0.16 0.02 12.0 1.6 75.2-20% 12% Weights in 000 tonnes. 1) SSB 2011 relative to SSB 2009. 2) Human consumption for IV (80% of HC Catch) 2010 relative to TAC for area IV and IIa in 2009. The human consumption landings in Divisions IV and VIId are calculated as 80% and 20% of the combined area total on the basis of estimates of landings for the past three years. Management considerations Catches of whiting have been declining since 1980 (from 224 000 t in 1980 to 27 000 t in 2008, including discards and industrial bycatch). Distribution maps of survey IBTS indices show a change in distribution of the stock which is now located mainly in the northwestern North Sea. Catch rates from localized fleets may not represent trends in the overall North Sea and English Channel population (Figure 6.4.5.3). The localized distribution of the population is known to be resulting in substantial differences in the quota uptake rate. This is likely to result in localized discarding problems that should be monitored carefully. Whiting are caught in mixed demersal roundfish fisheries, fisheries targeting flatfish, the Nephrops fisheries, and the Norway pout fishery. For management to be effective, both species-specific assessments and the latest developments in mixed fisheries approaches need to be considered. A reduction in direct effort on one stock may lead to a reduction or an increase in effort on another and, hence, the implications of any changes need to be identified and carefully evaluated. The current minimum mesh-size in the targeted demersal roundfish fishery in the northern North Sea has resulted in reduced discards from that sector compared with the historical discard rates. Mortality has increased on younger ages due to increased discarding in the recent year as a result of recent changes in fleet dynamics of Nephrops fleets and small mesh fisheries in the southern North Sea. The bycatch of whiting in the industrial Norway pout and sandeel fisheries is dependent on activity in that fishery, which has recently declined after strong reductions in the fisheries. These are low values based on the assumption of a similar bycatch rate to that observed in previous years, when the industrial fisheries were at a low level. A larger catch allocation for bycatch may be required if industrial effort increases (see Norway pout advice Section 6.4.20). Corrections made in November are presented in bold. 58 ICES Advice 2009, Book 6

Catches of whiting in the North Sea are also likely to be affected by the effort reduction seen in the targeted demersal roundfish and flatfish fisheries, although this will in part be offset by increases in the number of vessels switching to small mesh fisheries. Recent measures to improve survival of young cod, such as the Scottish Credit Conservation Scheme, and increased uptake of more selective gear in the North Sea and Skagerrak, should be encouraged for whiting. Following the EU Commission consultation paper on TACs for 2010 (COM(2009) 224, 12 May 2009) this stock would be categorised based on the average of SSB in the last 2 years compared to the average of the 3 preceding years. For this stock, this shows a reduction of 24%, resulting in a 15% reduction of the TAC. ICES has not evaluated this rule in relation to the precautionary approach. ICES has developed a generic approach to evaluate whether new survey information that becomes available in September forms a basis to update the advice. If this is the case, ICES will publish new advice in November 2009. Impact of fisheries on the ecosystems The effect on the benthic invertebrate community in the northern North Sea from all otter trawling is estimated to represent an annual mortality of approximately 25% of the standing-crop biomass. The MAFCONS STECF datasets suggest that otter trawl effort directed at fish has declined since 1999 (Greenstreet et al., 2007). Factors affecting the fisheries and the stock Regulations and their effects The human consumption TAC for whiting has not been taken for at least 20 years. The minimum mesh size increased to 120 mm in the northern area in 2002 and this may have contributed to the substantial decrease in reported landings. Landings compositions from the northern area, in 2006 and 2007, indicate improved survival of older ages. In addition, the total number of fish discarded appears to have been significantly reduced since 2003, from around 60% in 2003 to around 47% in 2008. Effort restrictions in the EC were introduced in 2003 (annual annexes to the TAC regulations) for the protection of the North Sea (?) cod stock. In 2009, the management program switched from a days at sea to a kw/day system (2009 Council Regulation (EC) N 43/2009), in which different amounts of kw/days are allocated within each area by Member State to different groups of vessels depending on gear and mesh size. In 2008, STECF indicated that overall effort (kw/days) by demersal trawls, seines and beam trawls had been substantially reduced since 2002. Fishing mortality declined between 2003 and 2007 concomitant with this effort reduction, but F increased again in 2008 despite a further nominal reduction in effort. Marked changes have also occurred in the use of the different mesh size categories by demersal trawlers. A sharp reduction has occurred in the use of mesh sizes between 100mm and 119mm, while a pronounced increase is apparent in the use of mesh sizes of 120mm and greater. As well, a general increase in effort has been observed in vessels using mesh sizes of 70-89mm and 90-99mm. Scotland implemented in February 2008 a national scheme known as the Conservation Credits Scheme. The principle of this two-part scheme involves additional time at sea in return for the adoption of measures which aims to reduce mortality on cod and lead to a reduction in discard numbers. ICES has not yet been able to evaluate the consequences of these measures. Despite their introduction, ICES notes that during the initial year of operation (2008) cod discarding rates increased substantially. Changes in fishing technology and fishing patterns The use of bigger meshes in the top panel of Belgium beam trawler gear is expected to reduce the bycatch of roundfish species, especially haddock and whiting. Scientific basis Data and methods The stock assessment is based on an XSA assessment, calibrated with two survey indices. Commercial catch-at-age data were disaggregated into human consumption, discards, and industrial bycatch components. Partial fishing mortalities from these catch components were calculated from their average contribution over 2006 2008. This could not be done on an area basis. Discards were estimated based on data from Scotland, England, Denmark and Germany and raised to the total international fleet in the North Sea. Discard information is now available for the years 2003 to 2008 for a major ICES Advice 2009, Book 6 59

component of the catch from French fleets fishing in Areas IV and VIId, these data will be incorporated in next years assessment. There are considerable discrepancies in stock trends prior to 1990 between the survey time-series and the assessment based on commercial catch data. Calibration data prior to 1990 were therefore omitted from the time-series. Information from the fishing industry The report of the North Sea Fishers Survey (Laurenson 2008) shows that the industry perception of whiting abundance since 2001 in general is at odds with the assessment, only no change or more was reported and in contrast the assessment indicates a continuously declining stock. However, the perception of an increasing stock around the eastern English coast (areas 4 and 5) is reflected in survey distribution plots. There is also a perception of increased discards in these areas. The UK industry has highlighted the continuing problem of the effect of the reduced TAC for whiting in specific areas of the North Sea where whiting abundance has been increasing in contrast to the decline in the wider North Sea. Whiting has been attracting high market value in the last three years and the cost of whiting quota has increased substantially resulting in higher discarding in some areas of high abundance due to the unavailability of affordable quota. This observation is consistent with the ICES advice that the localized distribution of the population is known to be resulting in substantial differences in the quota uptake rate. Uncertainties in assessment and forecast Discard estimates are based largely on the Scottish and English sampling programme, with the Scottish data getting three times the weight in the estimation but landing only approximately 50% of the total landings. Scottish sampling is mainly in the northern area. Because the fishery in the southern area is mostly carried out with different gears and smaller mesh sizes, this estmation will be a source of uncertainty in the assessment.. Comparison with previous assessment and advice The natural mortality values used in the assessment have been revised based on new estimates from the multi-species model. This has resulted in a substantial increase in the level of recruitment and reduction in the historic values of spawning biomass with a relatively minor reduction in the level of fishing mortality. The trends and the conclusions drawn from them remain unchanged. The basis of the advice has changed: the 2008 advice aimed for Fmax, this year the advice should result in a stable SSB. Sources of information Report of the Working Group on the Assessment of Demersal Stocks in the North Sea and Skagerrak, 6-12 May 2009. ICES CM 2009/ACOM:10. Greenstreet, S., Robinson, L., Piet, G., Craeymeersch, J., Callaway, R., Reiss, H., Ehrich, S., Kröncke, I., Fraser, H., Lancaster, J., Jørgensen, L., and Goffin, A. 2007. The ecological disturbance caused by fishing in the North Sea. Fisheries Research Services, Aberdeen, U.K. Collaborative Report No 04/07. 169 pp. STECF PLEN-08-03 EUR 23624 EN, ISBN 978-79-10940-9, ISSN 1018-5593, DOI 10.2788/3484, 2008 60 ICES Advice 2009, Book 6

ICES Advice 2009, Book 6 61 Table 6.4.5.1 Year ICES Advice Whiting in Subarea IV (North Sea). Single-stock exploitation boundaries (advice), management, and catch. Single-Stock Exploitation Boundaries Predicted landings corresp. to single-stock expl. boundaries advice** ICES Advice 2009, Book 6 61 Agreed TAC Off. Lndgs. ICES figures Hum. Indust. Disc. Total Cons. bycatch slip. catch 1989 Protect juveniles - 115 40 41 43 36 120 1990 80% of F(88); TAC 130 125 41 43 51 56 150 1991 70% of effort (89) - 141 47 47 38 34 119 1992 70% of effort (89) - 135 47 46 27 31 104 1993 70% of effort (89) - 120 47 48 20 43 111 1994 Significant reduction in effort; mixed fishery - 100 42 43 10 33 86 1995 Significant reduction in effort; mixed fishery - 81 41 41 27 30 98 1996 Mixed fishery; take into account cod advice - 67 35 36 5 28 69 1997 Mixed fishery; take into account cod advice - 74 32 31 6 17 54 1998 No increase from 1996 level 54 60 24 24 3 13 40 1999 at least 20% reduction of F(95 97) 40.4 44 25 26 5 24 55 2000 lowest possible catch 0 30 24 24 9 22 55 2001 60% reduction of F(97 99) 19.4 30 19 19 7 16 43 2002 F not larger than 0.37 33 32 16 16 7 17 40 2003 No cod catches - 16 11 11 3 24 38 2004 No cod catches *) Fishing mortality in 2004 should be < F pa No increase compared to recent years 16 9 9 1 14 25 2005 No cod catches *) Less than recent avg 52 28.5 10 11 1 11 22 2006 No cod catches *) Less than recent avg < 17.3 23.8 15 15 2 10 27 2007 No cod catches *) Less than recent avg <15.1 23.8 16 16 1 6 24 2008 No cod catches Less than recent avg <15.1 17.9 13 13 1 8 22 2009 No cod catches *) F < F max < 11 15.2 2010 No cod catches *) Stable SSB <7.4 Weights in 000 t. *) Single-stock boundary, and the exploitation of this stock should be conducted in the context of mixed fisheries protecting stocks outside safe biological limits. **) including Division VIId from 2005 onwards.

62 ICES Advice 2009, Book 6 Table 6.4.5.2 62 Year ICES Advice Whiting in Division VIId (Eastern Channel). Single-stock exploitation boundaries (advice), management, and catch/landings. Single-Stock Exploitation Boundaries Predicted landings corresp. to single-stock expl. boundaries advice** Agreed TAC 1 Official landings 1989 Precautionary TAC - - n/a 4.2 1990 No increase in F; TAC 8.0 2 - n/a 3.5 1991 F sq ; TAC 5.1 - n/a 5.7 1992 If required, precautionary TAC 6.0 2-5.9 5.7 1993 No basis for advice - - 5.4 5.2 1994 No long-term gains in increasing F - - 7.1 6.6 1995 Significant reduction in effort; link to North - - 5.6 5.4 1996 S Reference made to North Sea advice - - 5.1 5.0 1997 Reference made to North Sea advice - - 4.8 4.6 1998 Reference made to North Sea advice 5.8-4.8 4.6 1999 Reference made to North Sea advice 3.9 - n/a 4.4 2000 Lowest possible catch 0-6.1 4.3 2001 60% reduction of F sq 2.5-6.6 5.8 2002 F not larger than 0.37 <=4-5.4 5.8 2003 No cod catches - - 6.8 5.7 2004 No cod catches *) Fishing mortality Catch should not increase - 0.3 4.4 should be <F pa compared to recent years. 2005 No cod catches *) - - - 4.1 4.8 2006 No cod catches *) Less than recent < 17.3-3.3 3.4 average 2007 No cod catches *) Less than recent <15.1 2.9 3.3 average 2008 No cod catches *) Less than recent <15.1 3.8 4.5 average 2009 No cod catches *) F < F max < 11 2010 No cod catches *) Stable SSB <7.4 Weights in 000 t. 1 Included in TAC for Subarea VII (except Division VIIa). 2 Including VIIe. *) Single-stock boundary, and the exploitation of this stock should be conducted in the context of mixed fisheries protecting stocks outside safe biological limits. **) Includes both areas (IV and VIId). n/a = Not available. ICES Catch ICES Advice 2008, Book 6

Landings 60 50 Landings in 1000 t 40 30 20 10 0 1990 1995 2000 2005 F(ages 2-6) 0.9 0.8 0.7 0.6 0.5 0.4 0.3 0.2 0.1 0.0 Fishing Mortality 1990 1995 2000 2005 Recruitment in billions 3.5 3 2.5 2 1.5 1 0.5 0 Recruitment (age 1) 1990 1995 2000 2005 Figure 6.4.5.1 Whiting in Subarea IV and Division VIId. Summary of stock assessment: landings, fishing mortality, recruitment, and SSB. Predictions are shown shaded. ICES Advice 2009, Book 6 63

Stock - Recruitment Recruitment (age 1) in billions 3.5 3 2.5 2 1.5 1 0.5 0 0 50 100 150 200 250 300 350 400 SSB in 1000 t Yield and Spawning Stock Biomass per Recruit Yield (dashed line) 0.025 0.02 0.015 0.01 0.005 0 0 0.2 0.4 0.6 0.8 1 Fishing Mortality (ages 2-6) 0.16 0.14 0.12 0.1 0.08 0.06 0.04 0.02 0 SSB (line) Figure 6.4.5.2 Whiting in Subarea IV and Division VIId. Stock recruitment relationship and Yield and SSB per Recruit plot. 64 ICES Advice 2009, Book 6

Figure 6.4.5.3 Whiting in Subarea IV and Division VIId. Commercial landings (human consumption and industrial fisheries in tonnes) by ICES statistical rectangle over the years 1984 to 2007. The same scaling is used in each map. In the top left plot a + indicates where landings are reported / available in every year (1984 2007), indicates that for some years no landings were reported / available for that square. Danish industrial bycatch was available from 1988. French human consumption landings were available from 1999. ICES Advice 2009, Book 6 65

Figure 6.4.5.4 Whiting in Subarea IV and Division VIId. Results of the North Sea Commission fishers survey 2008. Whiting Sub-area IV (North Sea) & Division VIId (Eastern Channel) 450 400 350 SSB ('000 tonnes) 1.20 1.00 Fishing mortality: 2-6 5 4.5 4 Billions Recruitment. Age: 1 300 0.80 3.5 250 200 150 0.60 0.40 3 2.5 2 1.5 100 50 0.20 1 0.5 0 1990 1995 2000 2005 0.00 1990 1995 2000 2005 0 1990 1995 2000 2005 Figure 6.4.5.5 Whiting in Subarea IV and Division VIId. Comparison of current assessment with previous assessments. The change in Recruitment is caused by the use of increased values of natural mortality particularly at age 1 (increased from 0.95 to 1.4-1.7 based on WGSAM, 2008) this is also the cause of the increased SSB. 66 ICES Advice 2009, Book 6

Table 6.4.5.3 Whiting in Subarea IV and Division VIId. Catches (in tonnes) by country and by area. Subarea IV Country 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 Belgium 268 529 536 454 270 248 144 105 92 45 107 Denmark 46 58 105 105 96 89 62 57 251 78 42 Faroe Islands 1 1 0 0 17 5 0 0 0 0 0 France 1908 0 2527 3455 3314 2675 1721 1059 2445 2876 1788 Germany 103 176 424 402 354 334 296 149 252 75 76 Netherlands 1941 1795 1884 2478 2425 1442 977 802 702 618 656 Norway 65 68 33 44 47 38 23 16 18 11 92 Sweden 0 9 4 6 7 10 2 1 2 1 2 UK (E.&W) 2909 2268 1782 1301 1322 680 1209 2653 UK (Scotland) 16696 17206 17158 10589 7756 5734 5057 5361 UK (Total) 11481 12101 10386 Total 23938 22110 24453 18834 15608 11256 9491 10202 15242 15805 13149 Unallocated landings -78 3870 57 586 312-596 -261 308-95 381 250 WG estimate of H.Cons. 23860 25980 24510 19420 15920 10660 9230 10510 15147 16186 13399 landings WG estimate of 12710 23580 23210 16490 17510 24090 14260 10610 9540 6400 7990 discards WG estimate of Ind. Bycatch 3140 5180 8890 7360 7330 2740 1220 880 2190 1230 1020 WG estimate of total catch 39710 54740 56610 43270 40760 37490 24710 22000 26877 23816 22409 Division VIId Country 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 Belgium 53 48 65 75 58 66 45 45 71 75 68 France 4495-5875 6338 5172 6478-3819 3019 2648 3510 Netherlands 32 6 14 67 19 175 132 125 117 118 162 UK 185 135 118 134 112 109 80 86 71 59 (E.&W) UK + - - - - - - - - - (Scotland) UK (Total) 87 Total 4765 189 6072 6614 5361 6828 274 4074 3279 2899 3827 Unallocated -165 4241 - -814 439-4076 716 164 355 644 1772 1118 W.G. estimate 4600 4430 4300 5800 5800 5710 4350 4790 3443 3254 4471 ICES Advice 2009, Book 6 67

Table 6.4.5.4 Whiting in Subarea IV and Division VIId. Summary of stock assessment. Year Recruitment SSB Landings Catches Mean F Age 1 Ages 2-6 thousands tonnes tonnes Tonnes 1990 2942000 351202 46900 153460 0.85 1991 2798000 307582 53020 124970 0.69 1992 2694000 290762 52190 109700 0.68 1993 2991000 261806 53200 166170 0.68 1994 2778000 245073 49240 92600 0.79 1995 2449000 253569 46440 103260 0.74 1996 1680000 219413 41070 73950 0.68 1997 1284000 187871 35920 59100 0.52 1998 1832000 157403 28460 44310 0.50 1999 2883000 163066 30410 59170 0.56 2000 3239000 211039 28810 60910 0.67 2001 2617000 229483 25220 49070 0.46 2002 2295000 222115 21720 46560 0.30 2003 783000 179044 16370 43200 0.29 2004 901000 159813 13580 29060 0.23 2005 1124000 132850 15300 26790 0.26 2006 1063000 119812 18590 30320 0.37 2007 605000 98424 19440 27070 0.38 2008 1553000 87292 17870 26880 0.47 2009 1297000* 93582 3 Average 2027000 204085 32303 67187 0.53 * survey estimates 3 Corrections made in November are presented in bold. Because this is a marginal difference, the relating figures have not been updated from the June advice. 68 ICES Advice 2009, Book 6

6.4.6 Plaice in Division IIIa (Skagerrak Kattegat) Single-stock exploitation boundaries As in 2008, the new analysis available for this stock has not given a reason to change the advice from 2007. The advice on this stock for the fishery in 2010 is therefore the same as the advice given over the last 2 years: Landings should not exceed the level recorded in 2006 of 9400 t. In addition, ICES offers the following consideration: In 2007, ICES identified key issues that would need to be resolved before reaching further improvements in the assessment. The various surveys give a reasonably consistent result for the eastern part of the area. The status of the western part is more uncertain, due to potential mixing with North Sea plaice and limited survey coverage. The landings-at-age matrix does not show proper tracking of the cohorts, probably due to i) mixing of the IIIa stock with the North Sea plaice stock on the main fishing ground in southwestern Skagerrak, and ii) uncertainty in ageing due to low sampling levels. In 2009, ICES still considered these issues as outstanding, although uncertainty due to age reading is likely to have decreased in the recent years. This advice will be updated in 2011. Source of information Report of the Working Group on the Assessment of Demersal Stocks in the North Sea and Skagerrak, 6-12 May 2009 (ICES CM 2009/ACFM:10). Year ICES Advice Single-stock Exploitation Boundaries Predicted catch corresp. to advice Agreed TAC Kattegat Agreed TAC Skagerrak ICES Landings 1992 TAC 14.0 2.8 11.2 11.9 1993 Precautionary TAC - 2.8 11.2 11.3 1994 If required, precautionary TAC - 2.8 11.2 11.3 1995 If required, precautionary TAC - 2.8 11.2 10.8 1996 If required, precautionary TAC - 2.8 11.2 10.5 1997 No advice - 2.8 11.2 10.1 1998 No increase in F from the present 11.9 2.8 11.2 8.4 1999 No increase in F from the present 11.0 2.8 11.2 8.5 2000 F < F pa 11.8 2.8 11.2 8.8 2001 F < F pa 9.4 2.35 9.4 11.7 2002 F < F pa 8.5 1 1.6 2 6.4 2 8.7 2003 F < F pa 18.4 3.0 10.4 8.9 2004 3 F < F pa 3 1.8 9.5 9.1 2005 F < F pa < 9.5 1.9 7.6 6.9 2006 No increase in F < 9.6 1.92 7.68 9.4 2007 Maintain current <9.6 2.125 8.5 8.8 TAC 2008 No increase in catch <9.4 2.338 9.350 8.6 2009 Same advice as last year No increase in catch <9.4 2.338 9.350 2010 Same advice as last year No increase in catch <9.4 Weights in 000 t. 1) In March 2002 ACFM revised its advice to 11.6 for both areas combined. 2) The TAC for the two areas combined was adjusted to 11 200 tonnes in mid-2002. 3) Single-stock boundary and the exploitation of this stock should be conducted in the context of mixed fisheries. ICES Advice 2009, Book 6 69

Table 6.4.6.1 Plaice in Kattegat. Landings in tonnes. Working Group estimates, 1972 2008. Year Denmark Sweden Germany Belgium Norway Total 1972 15,504 348 77 15,929 1973 10,021 231 48 10,300 1974 11,401 255 52 11,708 1975 10,158 296 39 10,493 1976 9,487 177 32 9,696 1977 11,611 300 32 11,943 1978 12,685 312 100 13,097 1979 9,721 333 38 10,092 1980 5,582 313 40 5,935 1981 3,803 256 42 4,101 1982 2,717 238 19 2,974 1983 3,280 334 36 3,650 1984 3,252 388 31 3,671 1985 2,979 403 4 3,386 1986 2,470 202 2 2,674 1987 2,846 307 3 3,156 1988 1,820 210 0 2,030 1989 1,609 135 0 1,744 1990 1,830 202 2 2,034 1991 1,737 265 19 2,021 1992 2,068 208 101 2,377 1993 1,294 175 0 1,469 1994 1,547 227 0 1,774 1995 1,254 133 0 1,387 1996 2,337 205 0 2,542 1997 2,198 255 25 2,478 1998 1,786 185 10 1,981 1999 1,510 161 20 1,691 2000 1,644 184 10 1,838 2001 2,069 260 2,329 2002 1,806 198 26 2,030 2003 2,037 253 6 2,296 2004 1,395 137 77 1,609 2005 1,104 100 47 1,251 2006 1,355 175 20 1,550 2007 1,198 172 10 1,380 2008 866 137 6 1,008 * years 1972-1990 landings refers to IIIA 70 ICES Advice 2009, Book 6

Table 6.4.6.2 Plaice in Skagerrak. Landings in tonnes. Working Group estimates, 1972 2008. Year Denmark Sweden Germany Belgium Norway Netherlands Total 1972 5,095 70 3 5,168 1973 3,871 80 6 3,957 1974 3,429 70 5 3,504 1975 4,888 77 6 4,971 1976 9,251 51 717 6 10,025 1977 12,855 142 846 6 13,849 1978 13,383 94 371 9 13,857 1979 11,045 67 763 9 11,884 1980 9,514 71 914 11 10,510 1981 8,115 110 263 13 8,501 1982 7,789 146 127 11 8,073 1983 6,828 155 133 14 7,130 1984 7,560 311 27 22 7,920 1985 9,646 296 136 18 10,096 1986 10,645 202 505 26 11,378 1987 11,327 241 907 27 12,502 1988 9,782 281 716 41 10,820 1989 5,414 320 230 33 5,997 1990 8,729 779 471 69 10,048 1991 5,809 472 15 315 68 6,679 1992 8,514 381 16 537 106 9,554 1993 9,125 287 37 326 79 9,854 1994 8,783 315 37 325 91 9,551 1995 8,468 337 48 302 224 9,379 1996 7,304 260 11 428 8,003 1997 7,306 244 14 249 7,813 1998 6,132 208 11 98 6,449 1999 6,473 233 7 336 7,049 2000 6,680 230 5 67 6,982 2001 9,045 125 61 9,231 2002 6,470 140 3 58 6,671 2003 4,847 143 8 74 1,584 6,656 2004 5,717 179 106 1,511 7,513 2005 4,515 144 116 915 5,690 2006 6,334 175 14 142 1,190 7,855 2007 5,467 159 21 100 1,659 7,406 2008 6,901 219 5 79 403 7,607 ICES Advice 2009, Book 6 71

6.4.7 Plaice in Subarea IV (North Sea) State of the stock Spawning biomass in relation to precautionary limits Full reproductive capacity Fishing mortality in relation to precautionary limits Harvested sustainably Fishing mortality in relation to high long-term yield Overfished Fishing mortality in relation to agreed target Below target Comment Based on the most recent estimate of SSB (in 2009) and fishing mortality (in 2008), ICES classifies the stock as having full reproductive capacity and as being harvested sustainably. SSB is estimated to have increased above the B pa. Fishing mortality is estimated to have decreased to below F pa and F target. Recruitment has been of average strength from 2005 onwards. The recruitment in 2008 is just below the long-term average. Management objectives EC and Norway have no agreed management plan for North Sea plaice. However, the EC has adopted a management plan for flatfish in the North Sea in June 2007 (Council Regulation (EC) No. 676/2007, see 6.4.7 Appendix). This plan has two stages. The first stage aims at an annual 10% reduction of fishing mortality in relation to the fishing mortality estimated for the preceding year until an F of 0.3 is reached, with a maximum change in TAC of 15% until the precautionary reference points are reached for both plaice and sole for two successive years. ICES interprets the F for the preceding year as the estimate of F for the year in which the assessment is carried out. The basis for this F estimate in the preceding year will be a constant application of the procedure used by ICES in 2007. In the second stage, the management plan aims for exploitation at F = 0.3. ICES has evaluated the agreed long-term management plan (Council Regulation (EC) No. 676/2007) for plaice and sole. For plaice, the management plan evaluation is not yet conclusive with regards to consistency with the precautionary approach. Reference points Precautionary approach Type Value Technical basis B lim 160 000 t B loss = 160 000 t, the lowest observed biomass in 1997 as assessed in 2004. B pa 230 000 t Approximately 1.4 B lim. F lim 0.74 F loss for ages 2 6. F pa 0.60 5th percentile of F loss (0.6) and implies that B eq >B 1) pa and a 50% probability that SSB MT ~ B pa. Targets F mgt 0.3 EU management plan (unchanged since 2004, target added in 2008) Yield and spawning biomass per Recruit F-reference points (2009): Fish Mort Yield/R SSB/R Ages 2-6 Average last 3 years 0.31 0.09 0.55 Fmax 0.17 0.10 1.25 F0.1 0.12 0.10 1.74 Fmed 0.42 0.07 0.32 A candidate for the reference point consistent with taking high long-term yields and achieving a low risk of depleting the productive potential of the stock is F max. 72 ICES Advice 2009, Book 6

Single-stock exploitation boundaries Considering the options below, ICES advises on the basis of the existing EU management plan. Although the evaluation of the plan has not been conclusive, the fishing mortality in 2010 when applying the management plan is expected to give benefits in terms of long-term yield and low risk to the stock compared to fishing at precautionary levels. ICES therefore advises to limit landings to 63 825 t for the year 2010. Exploitation boundaries in relation to existing management plans According to the management plan adopted by the EU in 2007, the fishing mortality in 2010 should be at the target F (= 0.3) with the constraint that the change in TAC should not be more than 15%. In this case the 15% limit is the determining factor, resulting in a TAC of no more than 63 825t. Exploitation boundaries in relation to high long term yield, low risk of depletion of production potential and considering ecosystem effects The current total fishing mortality (including discards) is estimated to be 0.25, which is above the rate expected to lead to high long-term yields and low risk of stock depletion (Fmax). Exploitation boundaries in relation to precautionary limits The exploitation boundaries in relation to precautionary limits imply human consumption landings of less than 138 000 t in 2010, which is expected to maintain SSB above B pa in 2011, while maintaining F below F pa. Short-term implications Outlook for 2010 Basis: F(2009) = mean(f2006 2008) scaled to 2008 = 0.246; R(2009) = GM(1957 2006) = 912 907; Landings(2009) = 59.5 ; Discards(2009) = 43.8 ; SSB(2010) = 442. Rationale Landings 2010 Basis Disc (2010) Catch (2010) SSB (2011) %SSB change %TAC change F total (2 6) (2010) F HC (2 6) (2010) F disc (2 3) (2010) zero catch 0 F=0 0 0 0 0 0 596 +35% -100% High longterm yield 46.4 F(long-term yield) 0.17 0.17 0.17 31.2 77.5 517 +17% -16% Eu management 63.8 Fsq*0.978 0.24 0.24 0.25 42.5 106.3 488 +10% +15% plan Status quo 17.6 Fsq*0.25 0.06 0.06 0.06 12 29.6 566 +28% -68% 34.3 Fsq*0.50 0.12 0.12 0.13 23.2 57.5 538 +22% -38% 47 Fsq*0.70 0.17 0.17 0.18 31.6 78.6 516 +17% -15% 55.6 Fsq*0.84 0.21 0.21 0.21 37.2 92.8 502 +14% 0% 59.2 Fsq*0.90 0.22 0.22 0.23 39.5 98.7 496 +12% +7% 65.1 Fsq 0.25 0.25 0.25 43.3 108.4 486 +10% +17% 77.7 Fsq*1.22 0.3 0.3 0.31 51.3 129 465 +5% +40% 79.3 Fsq*1.25 0.31 0.31 0.32 52.3 131.7 462 +5% +43% 92.9 Fsq*1.50 0.37 0.37 0.38 60.7 153.6 439-1% +67% 105.8 Fsq*1.75 0.43 0.43 0.44 68.6 174.3 418-5% +91% 118 Fsq*2 0.49 0.49 0.51 75.9 193.9 398-10% +113% 138.1 Fsq*2.44 = Fpa 0.6 0.6 0.62 87.6 225.7 366-17% +149% 225.6 Fsq*4.98 1.23 1.23 1.26 133.9 359.5 230-48% +307% Weights in 000t. Shaded scenarios are not considered consistent with the precautionary approach. 1) SSB 2011 relative to SSB 2010 2) Landings 2010 relative to TAC 2009. ICES Advice 2009, Book 6 73

Management considerations Plaice is taken by beam trawlers in a mixed fishery with sole in the southern and central part of the North Sea with a minimum mesh size of 80 mm. In other areas plaice is also taken with larger mesh size, and by other gears. Technical measures applicable to the mixed flatfish fishery with beam trawls will affect both sole and plaice. The minimum mesh size of 80 mm selects sole at the minimum landing size. However, this mesh size generates high discards of plaice which are selected from 17 cm, while the minimum landing size is 27 cm. Recent discard estimates indicate fluctuations around 50% discards in weight. Mesh enlargement would reduce the catch of undersized plaice, but would also result in loss of marketable sole. For two succesive years, the stock has been classified within safe precautionary boundaries and thus fullfilled the 1st phase of the management plan. Although the estimates of the SSB and fishing mortality are uncertain, it is evident that the stock has increased considerably and the fishing mortality has been reduced. The increase in the stock has occurred under average recruitment conditions and is not caused by a higher productivity of the stock. The main reason for the increase of the SSB is the reduction of fishing mortality under the present management plan. Also a reduction of capacity in the fleets fishing for plaice, limitation of fishing effort and high fuel prices have contributed to the decrease in fishing mortality. Fishing effort has been substantially reduced since 1995, including the decommissioning of 25 vessels in 2008. The reduction in fishing effort is reflected in recent estimates of fishing mortality. There are indications that technical efficiency has increased in this fishery, which may have reduced the effect of the reduction in effort, but this may have been counteracted by decreases in fishing efficiency resulting from reduced fishing speed in an attempt to reduce fuel consumption The combination of days-at-sea regulations, high oil prices, and the decreasing TAC for plaice and the relatively stable TAC for sole, appear to have induced a more southern fishing pattern in the North Sea. This concentration of fishing effort results in increased discarding of juvenile plaice that are mainly distributed in those areas. This process could be aggravated by movement of juvenile plaice to deeper waters in recent years where they become more susceptible to the fishery. Also the lpue data show a slower recovery of stock size in the southern regions that may be caused by higher fishing effort in the more coastal regions. The assessment is considered to be highly uncertain, partly because discards form a substantial part of the total catch and cannot be well estimated from the low number of annual sampling trips, but most importantly due to the large differences in abundance observed in the different regions of the North Sea. The TAC constraint in the EU management plan is designed to allow for the uncertainty in the assessment. ICES has developed a generic approach to evaluate whether new survey information that becomes available in September forms a basis to update the advice. If this is the case, ICES will publish new advice in November 2009. Management plan evaluations In the 2008 evaluation of the management plan for plaice a number shortcomings were observed: - lack of robustness to the starting values of population abundance; - systematic over-estimation of historic landings; - under-estimation of bias and variance in the assessment model. Therefore ICES cannot presently conclude on the precautionary nature of the management plan for plaice. To be able to do so, the causes for the observed lack of robustness to the starting values need to be clarified. Additional evaluations should take into account various sources of assessment errors and include uncertainties associated with possible changes in discard practices. Uncertainties associated with the recent observed changes in the spatial distribution pattern of the stock and fishery, and the fact that some surveys and fishing fleets used in the assessment cover different parts of the stock distribution area need to be taken into account as well. Impacts of fisheries on the ecosystems Currently the mixed plaice and sole fishery is dominated by bottom trawls, with bycatch of both commercial and noncommercial species and a physical impact on the seabed. Bottom trawling reduces biomass, production, and species richness. For the North Sea, an ecosystem model showed that the bottom trawl fleet reduced benthic biomass and production by 56% and 21%, respectively, compared with an un-fished situation (Hiddink et al., 2006; Hinz et al., 2008). Chronic fishing has caused a shift from communities dominated by relatively sessile, emergent, high biomass species to communities dominated by infaunal, smaller-bodied fauna (Kaiser et al., 2000). 74 ICES Advice 2009, Book 6

Within species, the size selectivity may lead to a shift in the age and size at maturation. For example, plaice and sole become mature at younger ages and at smaller sizes in recent years than in the past. There is a risk that this shift is a genetic fisheries-induced change (Grift et al., 2004; Mollet et al., 2007). Factors affecting the fisheries and the stock Regulations and their effects The Dutch beam trawl fleet has reduced its number of vessels and technical management measures caused a shift towards two categories of vessels: 2000 HP (the maximum engine power allowed) and 300 HP. The 300 HP vessels are allowed to fish within the 12-nautical mile coastal zone and in the plaice box. A substantial number of the Dutch vessels have been replaced by vessels registered in other countries (England, Scotland, Germany, and Belgium). Approximately 85% of plaice landings from the UK (England and Scotland) is landed into the Netherlands by Dutch vessels fishing on the UK register. The technical efficiency has increased by about 1.6% per year in the plaice fishery since 1990, which could have counteracted part of the overall decrease in effort (Rijnsdorp et al., 2006). The overall capacity and effort of North Sea beam trawl vessels appears to have decreased since 1995. This decrease has continued in 2009 with the decommissioning of 25 Dutch trawl vessels. The minimum landing size of North Sea plaice is 27 cm. This minimum landing size results in high discarding levels in the mixed flatfish fishery with beam and bottom trawls using 80 mm mesh size. The Plaice Box is a closed area along the continental coast that has been introduced in 1989. The area has been closed all year round since 1995. The closed area applies to vessels using towed gears, but vessels smaller than 300 HP are exempted from the regulation. An STECF evaluation of the plaice box has indicated that: From trends observed it was inferred that the Plaice Box has likely had a positive effect on the recruitment of plaice but that its overall effect has decreased since it was established. There are two reasons to assume that the Plaice Box has a positive effect on the recruitment of plaice: 1) At present, the Plaice Box still protects the majority of undersized plaice. Approximately 70% of the undersized plaice are found in the Plaice Box and Wadden Sea. Despite the changed distribution, densities of juvenile plaice inside the Box are still higher than outside; 2) In the 80 mm fishery, discard percentages in the Box are higher than outside. Because more than 90% of the plaice caught in the 80 mm fishery in the Box are discarded, any reduction in this fishery would reduce discard mortality. (Grift et al., 2004). Changes in fishing technology and fishing patterns Due to a range of factors such as effort limitations, increases in fuel prices, and disproportionate changes in the TACs for the two main target species plaice and sole, the fishing effort of the major fleets has concentrated in the southern part of the North Sea. This is the area where many juvenile fish are found. In addition, juvenile plaice has shown a more offshore distribution in recent years. The combination of a change in fishing pattern and the spatial distribution of juvenile plaice has lead to an increase in discarding of plaice. Impacts of the environment on the fish stock Adult North Sea plaice have an annual migration cycle between spawning and feeding grounds. The spawning grounds are located in the central and southern North Sea, overlapping with the distribution area of sole. The feeding grounds are located more northerly than the sole distribution areas. Juvenile stages are concentrated in shallow inshore waters and move gradually offshore as they become larger. The nursery areas on the eastern side of the North Sea contribute most of the total recruitment. Sub-populations have strong homing behavior to specified spawning grounds and rather low mixing rate with other sub-populations during the feeding season. Juvenile plaice have been distributed more offshore in recent years. Surveys in the Wadden Sea have shown that 1- group plaice is almost absent from the area where it was very abundant in earlier years. This could be linked to environmental changes in the productivity or changes in the temperature of the southern North Sea, but these links have not been shown conclusively. The distribution shift of plaice may be the cause for the different abundance estimates in the different tuning series used in the assessment. ICES Advice 2009, Book 6 75

Scientific basis Data and methods The stock assessment is based on an age-based model (XSA) using landings and discards, calibrated with three survey indices: BTS-Tridens, BTS-Isis, and SNS. A Statistical Catch at Age model (Aarts & Poos 2009) has been run in parallel to the current XSA. The SCA model estimates similar stock trends compared to the XSA. Discards estimates are based on Dutch, UK, German, and Danish samples from observer programmes, on different fleet segments. For the years prior to 2000, discards were reconstructed based on a model-based analysis of growth, selectivity of the 80 mm beam trawl gear, and the availability of undersized plaice on the fishing grounds. Information from the fishing industry A self-sampling programme by the Dutch beam trawl fleet has been in place since 2004. This sampling effort indicates spatial and temporal trends in discarding; higher discards are observed in coastal regions and late summer. However, the self sampling gives overall lower estimates of discarding. This discrepancy is caused by differences in the implementations of different sampling methods (Aarts and van Helmond, 2009). The North Sea Fishers' Survey for 2008 resulted in a total of 303 responses. The large vessel group was dominated by respondents fishing with beam trawls (70%), stating that the plaice abundance is more and much more. This is consistent with the trends in the assessment. In terms of discarding, the modal response was that there was no change in discarding. Uncertainties in assessment and forecast The estimated increase in SSB is due to an increase in plaice observed in the survey in the north-western part of the North Sea. The surveys in the south-eastern part indicate that the stock has increased less. The different survey tuning series in different areas of the North Sea indicate different trends in the most recent development of the stock. This gives problems in the interpretation of the signals; this has resulted in a relatively strong retrospective pattern, with this years assessment estimating much higher SSBs and lower fishing mortalities for the most recent years. Discards form a substantial part of the total catch and cannot be well estimated from the limited number of sampling trips. The different trends in abundance in the two areas may indicate a change in distribution of older plaice, as has also been observed for juvenile plaice. However, the difference in distribution may also be explained by different exploitation rates in the two areas, with individual plaice in the more northern part susceptible to much lower fishing mortality. Comparison with previous assessment and advice In 2008 the SSB for 2008 was estimated at 265 kt, while this assessment estimates the SSB for that same year (2008) at 345 kt. Similarly, the F in 2007 was estimated at 0.39, while this year assessment estimates F in 2007 at 031. Last year ICES advised according to management plan aiming at a reduction in F of 10%. For this year, the basis of the advice in 2010 is to apply the EU management plan, corresponding to a 15% constraint on TAC increase. Sources of information Report of the Working Group on the Assessment of Demersal Stocks in the North Sea and Skagerrak, 6-12 May 2009 (ICES CM 2009/ACFM:10). Aarts, G. M., and van Helmond, A. T. M. 2007. Discard sampling of plaice (Pleuronectes platessa) and cod (Gadus morhua) in the North Sea by the Dutch demersal fleet from 2004 to 2006. IJmuiden, IMARES, Report C120/07, p. 42. Aarts, G.M.; Poos, J.J. (2009). Comprehensive discard reconstruction and abundance estimation using flexible selectivity functions. ICES Journal of Marine Science 66 (4). - p. 763-771. Grift, R. E., Tulp, I., Clarke, L., Damm, U., McLay, A., Reeves, S., Vigneau, J., and Weber, W. 2004. Assessment of the ecological effects of the Plaice Box. Report of the European Commission Expert Working Group to evaluate the Shetland and Plaice boxes. Brussels. 121 pp. Hiddink, J. G., Jennings, S., Kaiser, M. J., Queirós, A. M., Duplisea, D. E, and Piet, G. J. 2006. Cumulative impacts of seabed trawl disturbance on benthic biomass, production, and species richness in different habitats. Canadian Journal of Fisheries and Aquatic Sciences, 63: 721 736. Hinz, H., Hiddink, J. G., Forde, J., and Kaiser, M. J. 2008. Large-scale responses of nematode communities to chronic otter-trawl disturbance. Canadian Journal of Fisheries and Aquatic Sciences, 65: 723 732. 76 ICES Advice 2009, Book 6

Kaiser, M. J., Ramsay, K., Richardson, C. A., Spence, F. E., and Brand, A. R. 2000. Chronic fishing disturbance has changed shelf sea benthic community structure. Journal of Animal Ecology, 69: 494 503. Mollet, F. M., Kraak, S. B. M., and Rijnsdorp, A. D. 2007. Fisheries-induced evolutionary changes in maturation reaction norms in North Sea sole Solea solea. Marine Ecology Progress Series, 351: 189 199. Rijnsdorp, A. D., Daan, N., and Dekker, W. 2006. Partial fishing mortality per fishing trip: a useful indicator of effective fishing effort in mixed demersal fisheries. ICES Journal of Marine Science, 63: 556 566. Table 6.4.7.1 Plaice in Subarea IV (North Sea). Single stock exploitation boundaries (advice), management and landings. Single-stock exploitation boundaries Predicted Predicted catch catch corresponding corresponding to single-stock to advice boundaries Agreed Official ICES Year ICES Advice TAC landings landings 1987 F<F(84); TAC 120 150 131 154 1988 70% of F(85); TAC 150 175 138 154 1989 Reduce F; Buffer SSB <175 185 152 170 1990 status quo F; TAC 171 180 156 156 1991 No increase in F; TAC 169 175 144 148 1992 No long-term gains in increasing F - 1 175 123 125 1993 No long-term gains in increasing F 170 1 175 115 117 1994 No long-term gains in increasing F - 1 165 110 110 1995 Significant reduction in F 87 2 115 96 98 1996 Reduction in F of 40% 61 81 80 82 1997 Reduction in F of 20% 80 91 3 82 83 1998 Fish at F=0.3 82 87 70 72 1999 Fish at F=0.3 106 102 79 81 2000 Fish at F=0.3 95 97 84 81 2001 Fish at F=0.26 78 78 80 82 2002 F<F pa <77 77 70 70 2003 Fish at F=0.23 60 4 73 66 67 2004 Recovery plan - 61 61 61 2005 Rebuild the SSB above B pa in 2006 35 4 35 59 55 56 2006 Rebuild the SSB above B pa in 2007 48 4 57 56 58 2007 Rebuild the SSB above B pa in 2008 <32 4 50 49 50 2008 Rebuild the SSB above B pa in 2009 <35 4 49 48 49 2009 Limit total landings to 55 500 t < 55.5 4 55.5 2010 Limit total landings to 63 825 t <63.8 4 Weights in 000t. 1) Catch at status quo F. 2) Catch at 20% reduction in F. 3) After revision from 77 000 t. 4) Landings. ICES Advice 2009, Book 6 77

Figure 6.4.7.1 Plaice in Subarea IV (North Sea). Summary of stock assessment. Top left: Total catches (solid black line) landings (dotted line) and discards (dashed line); Top right: total fishing mortality (blue line), and fishing mortality of landings (red line); Bottom right: fishing mortality of discards. 78 ICES Advice 2009, Book 6

Figure 6.4.7.2 Plaice in Subarea IV (North Sea). SSB and recruitment, predicted values are shaded. ICES Advice 2009, Book 6 79

Stock - Recruitment 5 Recruitment (age 1) in billions 4.5 4 3.5 3 2.5 2 1.5 1 0.5 SSB-Rec. Blim Bpa 0 0 100 200 300 400 500 SSB in 1000 t Yield and Spawning Stock Biomass per Recruit 0.12 5 0.1 4.5 4 Yield (dashed line) 0.08 0.06 0.04 0.02 3.5 3 2.5 2 1.5 1 0.5 SSB (line) 0 0 0 0.1 0.2 0.3 0.4 0.5 0.6 Fishing Mortality (ages 2-6) SSB in 1000 t 500 450 400 350 300 250 200 150 100 50 0 Precautionary Approach Plot Period 1957-2008 0.0 0.2 0.4 0.6 0.8 1.0 Fishing Mortality (ages 2-6) F-SSB 2008 Flim Fpa Blim Bpa Figure 6.4.7.3 Plaice in Subarea IV (North Sea). Yield per recruit analysis and stock recruitment plot. 80 ICES Advice 2009, Book 6

Figure 6.4.7.4 Plaice in Subarea IV (North Sea). Results of the North Sea Commission fishers survey 2008. Plaice Subarea IV (North Sea) 500 450 SSB ('000 tonnes) 1.00 0.90 Fishing mortality: 2-6 2500 Millions Recruitment. Age: 1 400 0.80 2000 350 0.70 300 0.60 1500 250 0.50 200 0.40 1000 150 0.30 100 0.20 500 50 0.10 0 1990 1995 2000 2005 0.00 1990 1995 2000 2005 0 1990 1995 2000 2005 Figure 6.4.7.5 Plaice in Subarea IV (North Sea). Comparison of current assessment with previous assessments. Note the change in assessment methodology from 2004 onwards. ICES Advice 2009, Book 6 81

Table 6.4.7.2 Plaice in Subarea IV (North Sea). Nominal landings by country and area (tonnes). YEAR Belgium Denmark France Germany Netherlands Norway Sweden UK Others Total Unallocated WG estimate TAC 1980 7005 27057 711 4319 39782 15 7 23032 101928 38023 139951 1981 6346 22026 586 3449 40049 18 3 21519 93996 45701 139697 105000 1982 6755 24532 1046 3626 41208 17 6 20740 97930 56616 154546 140000 1983 9716 18749 1185 2397 51328 15 22 17400 100812 43218 144030 164000 1984 11393 22154 604 2485 61478 16 13 16853 114996 41153 156149 182000 1985 9965 28236 1010 2197 90950 23 18 15912 148311 11527 159838 200000 1986 7232 26332 751 1809 74447 21 16 17294 127902 37445 165347 180000 1987 8554 21597 1580 1794 76612 12 7 20638 130794 22876 153670 150000 1988 11527 20259 1773 2566 77724 21 2 24497 43 138412 16063 154475 175000 1989 10939 23481 2037 5341 84173 321 12 26104 152408 17410 169818 185000 1990 13940 26474 1339 8747 78204 1756 169 25632 156261-21 156240 180000 1991 14328 24356 508 7926 67945 560 103 27839 143565 4438 148003 175000 1992 12006 20891 537 6818 51064 836 53 31277 123482 1708 125190 175000 1993 10814 16452 603 6895 48552 827 7 31128 115278 1835 117113 175000 1994 7951 17056 407 5697 50289 524 6 27749 109679 713 110392 165000 1995 7093 13358 442 6329 44263 527 3 24395 96410 1946 98356 115000 1996 5765 11776 379 4780 35419 917 5 20992 80033 1640 81673 81000 1997 5223 13940 254 4159 34143 1620 10 22134 81483 1565 83048 91000 1998 5592 10087 489 2773 30541 965 2 19915 1 70365 1169 71534 87000 1999 6160 13468 624 3144 37513 643 4 17061 78617 2045 80662 102000 2000 7260 13408 547 4310 35030 883 3 20710 82151-1001 81150 97000 2001 6369 13797 429 4739 33290 1926 3 19147 79700 2147 81847 78000 2002 4859 12552 548 3927 29081 1996 2 16740 69705 512 70217 77000 2003 4570 13742 343 3800 27353 1967 2 13892 65669 820 66489 73250 2004 4314 12123 231* 3649 23662 1744 1 15284 61008 428 61436 61000 2005 3396 11385 112 3379 22271 1660 0 12705 54908 792 55700 59000 2006 3487 11907 132 3599 22764 1614 0 12429 55933 2010 57943 57441 2007 3866 8128 144 2643 21465 1224 4 11557 49031 713 49744 50261 2008 3396 8229 125 3138 20312 1051 20 11411 47682 1193 48875 49000 2009 55500 82 ICES Advice 2009, Book 6

Table 6.4.7.3 Plaice in Subarea IV (North Sea). Summary of stock assessment. Recruitment Age 1 (thousands) SSB Catch Landings Discards Mean F Landings ages 2-6 Mean F Discards ages 2-3 Mean F (tonnes) (tonnes) (tonnes) (tonnes) Total ages 2-6 1957 457973 274205 78423 70563 7860 0.27 0.22 0.12 1958 698110 288540 88240 73354 14886 0.32 0.24 0.19 1959 863386 296825 109238 79300 29938 0.37 0.24 0.24 1960 757298 308164 117138 87541 29597 0.37 0.27 0.23 1961 860575 321353 118331 85984 32347 0.35 0.24 0.27 1962 589153 372863 125272 87472 37800 0.39 0.25 0.29 1963 688365 370372 148170 107118 41052 0.42 0.27 0.36 1964 2231496 363076 147357 110540 36817 0.47 0.3 0.32 1965 694571 344012 139820 97143 42677 0.39 0.28 0.25 1966 586775 361547 166784 101834 64950 0.4 0.24 0.34 1967 401292 416560 163178 108819 54359 0.43 0.25 0.32 1968 434274 402516 139503 111534 27969 0.34 0.21 0.22 1969 648862 377425 142896 121651 21245 0.34 0.25 0.17 1970 650568 333925 160026 130342 29684 0.48 0.35 0.28 1971 410258 316330 136932 113944 22988 0.38 0.29 0.22 1972 366600 319043 142495 122843 19652 0.41 0.33 0.19 1973 1311938 268690 143883 130429 13454 0.47 0.41 0.13 1974 1132612 278608 157804 112540 45264 0.49 0.41 0.2 1975 864628 293068 195154 108536 86618 0.56 0.37 0.43 1976 692495 310834 167089 113670 53419 0.42 0.3 0.27 1977 988392 316735 176691 119188 57503 0.51 0.34 0.31 1978 911977 303134 159727 113984 45743 0.47 0.36 0.22 1979 890115 296622 213422 145347 68075 0.67 0.49 0.36 1980 1125334 271634 171235 139951 31284 0.56 0.49 0.16 1981 866020 260703 172671 139747 32924 0.54 0.47 0.16 1982 2030236 262013 204286 154547 49739 0.61 0.51 0.22 1983 1306336 311165 218424 144038 74386 0.6 0.49 0.26 1984 1258598 322582 226930 156147 70783 0.59 0.44 0.28 1985 1846346 344928 220928 159838 61090 0.54 0.44 0.23 1986 4750659 369768 296876 165347 131529 0.66 0.5 0.34 1987 1950224 442035 342985 153670 189315 0.7 0.49 0.51 1988 1769839 387569 311635 154475 157160 0.68 0.4 0.52 1989 1187325 408029 277738 169818 107920 0.62 0.38 0.46 1990 1036310 378736 228734 156240 72494 0.58 0.39 0.39 1991 913820 346093 229607 148004 81603 0.67 0.43 0.47 1992 776857 279778 183284 125190 58094 0.64 0.43 0.4 1993 531067 241954 152242 117113 35129 0.64 0.5 0.28 1994 442720 216682 134392 110392 24000 0.62 0.51 0.24 1995 1162817 207539 120316 98356 21960 0.65 0.56 0.21 1996 1290188 180465 133797 81673 52124 0.68 0.52 0.35 1997 2148532 197379 179957 83048 96909 0.79 0.51 0.69 1998 776201 226574 175002 71534 103468 0.74 0.39 0.6 1999 844549 202179 151708 80662 71046 0.67 0.38 0.38 2000 983135 231029 126142 81148 44994 0.48 0.32 0.26 2001 540793 271129 182578 81963 100615 0.78 0.32 0.72 2002 1712546 196790 125884 70217 55667 0.59 0.38 0.43 2003 546025 222231 145390 66502 78888 0.63 0.39 0.46 2004 1261256 203118 117702 61436 56266 0.5 0.3 0.43 2005 789082 236119 111060 55700 55360 0.42 0.21 0.38 2006 947769 247639 121205 57943 63262 0.38 0.2 0.39 2007 1031601 253712 90283 49744 40539 0.31 0.15 0.34 2008 890569 344871 96040 48874 47166 0.25 0.13 0.25 2009 912907* 388131 * Recruitment GM (1957 2006). ICES Advice 2009, Book 6 83

6.4.7 Appendix Extract from Council Regulation (EC) No 676/2007 of 11 June 2007 establishing a multiannual plan for fisheries exploiting stocks of plaice and sole in the North Sea: Article 7 Procedure for setting the TAC for plaice: 1) The Council shall adopt the TAC for plaice at that level of catches which, according to a scientific evaluation carried out by STECF is the higher of: a) that TAC the application of which will result in a 10 % reduction in the fishing mortality rate in its year of application compared to the fishing mortality rate estimated for the preceding year; b) that TAC the application of which will result in the level of fishing mortality rate of 0.3 on ages two to six years in its year of application. 2) Where application of paragraph 1 would result in a TAC which exceeds the TAC of the preceding year by more than 15 %, the Council shall adopt a TAC which is 15 % greater than the TAC of that year. 3) Where application of paragraph 1 would result in a TAC which is more than 15 % less than the TAC of the preceding year, the Council shall adopt a TAC which is 15 % less than the TAC of that year. 84 ICES Advice 2009, Book 6

6.4.8 Plaice in Division VIId (Eastern Channel) State of the stock Spawning biomass in relation to precautionary limits Fishing mortality in relation to precautionary limits Fishing mortality in relation to high long-term yield Fishing mortality in relation to agreed management targets Unknown Unknown Unknown Unknown Comment The assessment is indicative of trends only. The SSB trends suggest that the spawning-stock biomass has declined through the last 15 years to a stable historical low level. The current level of SSB is low. F varies without trend around the long-term average. Recruitment in 2006 and 2007 have been above average. Management objectives There are no explicit management objectives for this stock. Reference points Precautionary approach Type Value Technical basis B lim 5,600 t B loss (~1995) B pa 8,000 t 1.4 B lim F lim 0.54 F loss (~1995) F pa 0.45 5th percentile of F loss ; long-term SSB >B pa and P(SSB MT <B pa ) < 10%. Targets F y Not defined (unchanged since 1998) Single-stock exploitation boundaries In the absence of a short-term forecast, ICES advises on the basis of exploitation boundaries in relation to precautionary considerations that landings in 2010 should not increase above the average of landings from the last three years (2006 2008), corresponding to landings less than 3 500 t. Management considerations There is a limited directed fishery on plaice at the beginning of the year on the spawning grounds. This fishery catches plaice that originates from both the North Sea and VIId components. However, plaice is mainly taken as bycatch in the demersal fisheries, especially in the fisheries targeting sole. Due to the minimum mesh size (80 mm) in the mixed beam trawl fishery, a large number of undersized plaice are discarded. The 80-mm mesh size is not matched to the minimum landing size of plaice (27 cm). Measures taken specifically directed at sole fisheries will also impact the plaice fisheries. Following the EU Commission consultation paper on TACs for 2010 (COM(2009) 224, 12 May 2009) this stock would be categorised based on the average of SSB in the last 2 years compared to the average of the 3 preceding years. For this stock only relative measures of stock biomass are available but these show a reduction of 3%, resulting in an unchanged TAC. ICES has not evaluated this rule in relation to the precautionary approach. Factors affecting the fisheries and the stock The effects of regulations In previous years, effort from the beam trawl fleet has not been restricted. The new EU Council Regulation (EC) N 43/2009 does not reduce the effort for this fleet. ICES Advice 2009, Book 6 85

Scientific basis Data and methods The XSA exploratory assessment is valid for trends only and is based on reported landings data, three commercial cpue indices, and three survey indices. Time-series of discard data are not available, but observations from all fisheries from 2003 indicate that discards are high. Uncertainties in assessment and forecast There is uncertainty about the stock structure. Historical tagging information shows that around 40% of the juvenile plaice in Division VIId come from nursery grounds in the North Sea, while the Eastern Channel supplies very few recruits to the North Sea. Similarly, around 20% of the recruits in Division VIIe come from VIId, while VIId does not receive significant numbers of juvenile from VIIe. There is also an adult migration between the North Sea and the Channel 20 30% of the plaice caught in the winter in VIId were from migratory North Sea fish. The available information also suggests that plaice may migrate from the VIIe into the VIId and the North Sea after spawning. Lack of discarding information also adds to the uncertainty. Routine discard sampling began in 2003 following the introduction of the EU Data Collection Regulations and indicates percentages of discards up to 50% in number, depending on the trip and on fishing practices. However, the time-series of discards is not yet long enough to be used in an analytical assessment. Comparison with previous assessment and advice The assessment was considered unreliable due to problems in stock structure identity and the absence of discards in the assessment. This year s advice is similar to last year s advice which was not to exceed average recent landings. Source of information Report of the Working Group on the Assessment of Demersal Stocks in the North Sea and Skagerrak, 6-12 May 2009 (ICES CM 2009/ACOM:10). 86 ICES Advice 2009, Book 6

Table 6.4.8.1 Plaice in Division VIId. Single stock exploitation boundaries (advice), management and landings. Year ICES Advice (Single-stock Exploitation Boundaries since 2004) Predicted catch corresp. to advice Agreed TAC 1 Official landings ICES landings 1987 Precautionary TAC 1 6.8 1 8.3 7.9 8.4 1988 Precautionary TAC 1 6.9 1 9.96 9.1 10.4 1989 No increase in effort 1 11.7 1 11.7 6.7 2 8.8 1990 No increase in F; TAC 10.7 1 10.7 7.8 2 9.0 1991 TAC 8.8 1 10.7 7.4 2 7.8 1992 Status quo F gives mean SSB 7.6 3 9.6 6.2 6.3 1993 Within safe biological limits 6.4 3 8.5 4.8 5.3 1994 No long-term gains in increased F - 9.1 5.6 6.1 1995 No increase in F 5.6 8.0 4.6 5.1 1996 No long-term gains in increasing F 6.5 7.53 4.6 5.4 1997 No advice - 7.09 5.3 6.3 1998 Reduce F in 98 by 30% from 96 4.3 5.7 4.8 5.8 1999 Fishing at F pa 6.3 7.4 5.4 6.3 2000 Fishing at F pa 4.9 6.5 5.2 6.0 2001 Fishing at <F pa <4.4 6.0 5.0 5.3 2002 Fishing at <F pa <5.8 6.7 5.5 5.8 2003 Fishing at <F pa <5.3 6.0 4.5 4.5 2004 *) Fishing at <F pa <5.4 6.06 4.0 4.0 2005 *) Fishing at <F pa <4.4 5.15 3.0 3.4 2006 No effort increase *) 5.15 3.3 3.3 2007 Average landings *) <4.0 5.08 3.7 3.7 2008 Average landings *) <3.5 5.05 3.5 3.5 2009 Average landings *) <3.5 4.64 2010 Average landings *) <3.5 Weights in 000 t. 1 TACs for Divisions VIId,e. 2 For France Division VIId landings are estimated by ICES from the combined VIId,e landings. 3 Catch at status quo F. *) Single-stock boundary and the exploitation of this stock should be conducted in the context of mixed fisheries. ICES Advice 2009, Book 6 87

Fishing Mortality F(ages 2-6) F 1980 1985 1990 1995 2000 2005 Recruitment (age 1) Recruitment 1980 1985 1990 1995 2000 2005 Spawning Stock Biomass SSB SSB 1980 1985 1990 1995 2000 2005 Figure 6.4.8.1 88 Plaice in Division VIId (Eastern Channel). Landings (in 000 t), fishing mortality, recruitment, and SSB. Indicative of trends only. ICES Advice 2009, Book 6

Table 6.4.8.2 Plaice in Division VIId. Catches/landings by country and by area (in '000 t). Year Belgium Denmark France UK(E+W) Others Total Un- Total as reported allocated used by WG 1976 147 1(1) 1439 376-1963 - 1963 1977 149 81(2) 1714 302-2246 - 2246 1978 161 156(2) 1810 349-2476 - 2476 1979 217 28(2) 2094 278-2617 - 2617 1980 435 112(2) 2905 304-3756 -1106 2650 1981 815-3431 489-4735 34 4769 1982 738-3504 541 22 4805 60 4865 1983 1013-3119 548-4680 363 5043 1984 947-2844 640-4431 730 5161 1985 1148-3943 866-5957 65 6022 1986 1158-3288 828 488 (2) 5762 1072 6834 1987 1807-4768 1292-7867 499 8366 1988 2165-5688 (2) 1250-9103 1317 10420 1989 2019 + 3265 (1) 1383-6667 2091 8758 1990 2149-4170 (1) 1479-7798 1249 9047 1991 2265-3606 (1) 1566-7437 376 7813 1992 1560 1 3099 1553 19 6232 105 6337 1993 877 +(2) 2792 1075 27 4771 560 5331 1994 1418 + 3199 993 23 5633 488 6121 1995 1157-2598 (2) 796 18 4569 561 5130 1996 1112-2630 (2) 856 + 4598 795 5393 1997 1161-3077 1078 + 5316 991 6307 1998 854-3276 (23) 700 + 4830 932 5762 1999 1306-3388 (23) 743 + 5437 889 6326 2000 1298-3183 752 + 5233 781 6014 2001 1346-2962 655 + 4963 303 5266 2002 1204 3454 841 5499 278 5777 2003 995-2783 (3) 756 4536-4536 2004 987 2439 (4) 580 4007-4007 2005 830 1756 411 20 3018 428 3446 2006 1031 1713 545 16 3305-3305 2007 1356 1858 460 3674-3674 2008 1388 1642 461 3491-3491 1 Estimated by the working group from combined Division VIId+e 2 Includes Division VIIe 3 Provisional 4 Data provided to the WG but not officially provided to ICES ICES Advice 2009, Book 6 89

6.4.9 Sole in Division IIIa (Skagerrak and Kattegat) State of the stock Spawning biomass in relation to precautionary limits Full reproductive capacity Fishing mortality in relation to precautionary limits Fishing mortality in relation to high longterm yield Harvested sustainably Appropriate NA Fishing mortality in relation to agreed management target Comment Based on the most recent estimates of SSB (in 2009) and F (in 2008), ICES classifies the stock as having full reproductive capacity and being harvested sustainably. SSB has decreased since 2005 but is still well above B pa. Fishing mortality has increased from 0.22 in 2007 to 0.28 in 2008. Recruitment has been below average in recent 4 years. Management objectives There are no management objectives for this stock. Reference points Precautionary approach Type Value Technical basis B lim 770 t B pa *exp(-1.645*0.2) B pa 1060 t MBAL F lim 0.47 F med 98 excluding the abnormal years around 1990 F pa 0.30 consistent with F lim Targets F y not defined (unchanged since 1999) Yield and spawning biomass per Recruit F-reference points: Fish Mort Yield/R SSB/R Ages 4-8 Average last 3 years 0.27 0.19 0.88 F max * F0.1 0.17 0.17 1.19 F med 0.38 0.20 0.68 * F max not well defined Candidates for reference points which are consistent with high long-term yields and a low risk of depleting the productive potential are in the range of F 0.1 to F pa. Single-stock exploitation boundaries ICES advises on the basis of exploitation boundaries in relation to precautionary limits that fishing mortality in 2010 should be kept below F pa, corresponding to landings of less than 620 t. 90 ICES Advice 2009, Book 6

Short-term implications Basis: F(2009) = F sq = mean F(06 08) rescaled to the last year = 0.28; R94 06 = GM = 3.1 million; SSB(2009) =2.4; SSB(2010) = 2.3; landings (2009) = 0.57. Rationale Landings (2010) Basis F(2010) SSB(2011) %SSB change 1 %TAC change 2 Zero catch 0 F=0 0 2.90 24% -100% Status quo 0.58 F sq 0.28 2.31-1% -28% 0.07 F pa *0.1 0.03 2.83 21% -91% 0.17 F pa *0.25 0.08 2.73 16% -79% 0.33 F pa *0.5 0.15 2.57 9% -59% 0.58 F pa *0.73 = F sq 0.28 2.31-1% -40% 0.56 F pa *0.9 0.27 2.33-1% -30% Precautionary limits 0.62 F pa = F sq *1.08 0.30 2.27-3% -23% 0.67 F pa *1.1 0.33 2.22-5% -16% 0.75 F pa *1.25 0.38 2.14-9% -6% 0.87 F pa *1.5 0.45 2.02-14% 9% 0.99 F pa *1.75 0.53 1.90-19% 23% All weights in thousand tonnes. Shaded scenarios are not considered consistent with the precautionary approach. 1) SSB 2011 relative to SSB 2010. 2) Landings 2010 relative to TAC 2009. Management considerations The fishery for sole in the adjacent Belt Sea has increased in recent years with landings of about 15-20% of the landings in Kattegat and Skagerrak. The TAC applies to all of the Divisions IIIa, b, c, and d (i.e. the Skagerrak, the Kattegat, and both the Western and the Eastern Baltic) although the advice is based on the state of the stock in Division IIIa only. The stock structure must be investigated to determine to what extent sole in the Belt Sea belong to the same stock unit as sole in Kattegat/Skagerrak and consequently whether they should be managed together or separately. During the period 2002 2004 there was considerable misreporting due to limiting TACs and weekly quota. Since mid- 2005, the increase in TAC and improved control appears to have resulted in negligible misreporting. Sole is taken in a directed trawl fishery with bycatch of Nephrops and cod. Cod in the Kattegat is considered to be severely depleted. Also, sole is taken as bycatch in the Nephrops trawl fishery. There is a directed gillnet fishery for sole. Regulations and their effects The Danish fishery has in the past been regulated by half-monthly quotas which depended on vessel length and varied over the year. From 2007 a vessel quota share system (VQS) was put in force, allowing fishers to trade quotas and to decide when to fish them. The VQS was fully implemented during late 2007. The logbook data do not indicate any effects of the VQS on seasonal/spatial effort distribution. The management area includes Division IIIa plus the Western Baltic (Subdivisions 22 24). Danish vessel quota shares cover the management area and there is therefore no incentive to misreport sole taken in Division IIIa into the Western Baltic. Factors affecting the fisheries and the stock Changes in fishing technology and fishing patterns There are no major changes in the sole-directed fishery in recent years. Changes in the regulations for the Nephrops fishery, with the introduction of a sorting grid system in the trawls, may have resulted in smaller bycatch and improved selectivity on sole. Since 1 February 2008 exit square mesh panels have been mandatory in the trawl fishery to prevent by-catches of cod. This device is not expected to influence the sole catches. ICES Advice 2009, Book 6 91

Impact of the environment on the fish stock The stock is probably influenced by both temperature and salinity because it is located near the species physiological limits for both of these factors. Scientific basis Data and methods The analytical XSA assessment includes cpue data from three commercial tuning series (reference fleets) and one scientific survey series. Discarding is not assumed to occur to any extent of importance to the assessment and is not included. During the period 2002 2004 there was considerable misreporting due to limiting TACs and weekly quota which were included in the assessment. Since mid-2005, the increase in TAC and improved control are believed to have resulted in insignificant misreporting. Information from the fishing industry Collaboration between the Danish Fishers Organization and DTU Aqua was initiated in 2004 to establish a database with data from private logbooks. Haul-specific data from six trawlers and three gillnetters covering the time period 1987 to 2008 were used in the assessment. However, the gillnetter information was not available in 2008. Uncertainties in assessment and forecast The assessment is considered uncertain; in recent years there is a tendency to overestimate SSB. There is a need for fishery-independent data as the current survey does not target sole. A sole-directed research survey was initiated in 2004, and the time-series of catch rates will be considered in 2010 when it is sufficiently long and when the survey has been evaluated as an abundance index. If the share of catches in the Belt Sea remains important and if the population, in that area belongs to the IIIa stock the basis for the assessment and advice should include catches from the Belt Sea. Comparison with previous assessment and advice The present assessment has revised the perception of the recent levels of SSB and F as SSB in 2008 has been overestimated by 30%, while estimates of F in 2007 has been underestimated by 5%. (Figure 6.4.9.3). The basis for present advice is the same as last year. Source of information Report of the Baltic Fisheries Assessment Working Group. Copenhagen, 22-28 April 2009 (ICES CM 2009/ACOM:06). 92 ICES Advice 2009, Book 6

Table 6.4.9.1 Sole in Division IIIa. Single stock exploitation boundaries (advice), management and landings. Year ICES Advice Single-stock exploitation boundaries Predicted catch corresp. to advice Weights in 000 t. 1) Uncertain. 2) TAC applies to Division IIIa and the EC waters of Divisions IIIb and IIIc, d. Predicted catch corresp. to single-stock exploitation boundaries Agreed TAC 2 ICES Landings 1987 - - 0.85 0.72 1988 - - 0.95 0.71 1989 TAC <0.8 0.80 0.82 1990 Precautionary TAC 0.6 0.50 1.05 1991 TAC 1.0 1.00-1 1992 TAC 1.0 1.40-1 1993 TAC at recent catch levels 1.0 1.60-1 1994 No advice due to uncertain catches - 2.10 1.20 1995 No advice - 2.25 1.30 1996 No advice - 2.25 1.10 1997 No advice - 2.25 0.81 1998 No advice - 1.80 0.61 1999 No increase in F 0.8 1.35 0.64 2000 No increase in F 0.65 0.95 0.63 2001 No increase in F 0.7 0.70 0.46 2002 F below F pa 0.5 0.50 0.84 2003 F below F pa 0.3 0.35 0.60 2004 F below F pa 0.5 0.52 0.78 2005 No increase in F 0.85 0.90 0.82 2006 F below F pa 0.82 0.90 0.73 2007 Limit catches to 2002 2005 average 0.74 0.90 0.54 2008 keep F below F pa 0.97 0.94 0.54 2009 keep F below F pa 0.80 0.80 2010 keep F below F pa 0.62 ICES Advice 2009, Book 6 93

Landings in 1000 t 1.6 1.4 1.2 1 0.8 0.6 0.4 0.2 0 Landings 1984 1989 1994 1999 2004 0.7 0.6 0.5 Fishing Mortality F(ages 4-8) 0.4 0.3 0.2 0.1 0.0 1984 1989 1994 1999 2004 F Flim Fpa Recruitment in millions Recruitment (age 2) 10 9 8 7 6 5 4 3 2 1 0 1984 1989 1994 1999 2004 SSB in 1000 t Spawning Stock Biomass 6 5 4 3 2 1 0 1984 1989 1994 1999 2004 2009 SSB Blim Bpa Figure 6.4.9.1 Sole in Division IIIa. Landings, fishing mortality, recruitment, and SSB. Predicted values are shaded. 94 ICES Advice 2009, Book 6

Recruitment (age 2) in millions Stock - Recruitment 10 9 8 7 6 5 4 3 2 1 0 0 1 2 3 4 5 6 SSB in 1000 t SSB-Rec. Blim Bpa Yield (dashed line) Yield and Spawning Stock Biomass per Recruit 0.25 0.2 0.15 0.1 0.05 3.5 3 2.5 2 1.5 1 0.5 SSB (line) 0 0 0 0.1 0.2 0.3 0.4 0.5 0.6 Fishing Mortality (ages 4-8) Precautionary Approach Plot Period 1984-2008 SSB in 1000 t 6 5 4 3 2 1 0 0.0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 Fishing Mortality (ages 4-8) F-SSB 2008 Flim Fpa Blim Bpa Figure 6.4.9.2 Sole in Division IIIa. Stock recruitment, yield, and precautionary approach. ICES Advice 2009, Book 6 95

6 5 SSB ('000 tonnes) 0.70 0.60 Fishing mortality: 4-8 10 9 8 Millions Recruitment. Age: 1 4 0.50 7 0.40 6 3 2 0.30 0.20 5 4 3 1 0.10 2 1 0 1990 1995 2000 2005 0.00 1990 1995 2000 2005 0 1990 1995 2000 2005 Figure 6.4.9.3 Sole in Division IIIa. Historical performance of the assessments. Note: some of the earlier assessments were considered valid for trends only. 96 ICES Advice 2009, Book 6

Table 6.4.9.2 Sole in Division IIIa. Catches (tonnes) in the Kattegat and Skagerrak 1952 2008. Official statistics and Working Group corrections. For Sweden there is no information 1962 1974. Year Denmark Sweden Germany Belgium Netherlands Working Group Total Kattegat Skagerrak Skag+Kat Kat+Skag Skagerrak Skagerrak Corrections 1952 156 51 59 266 1953 159 48 42 249 1954 177 43 34 254 1955 152 36 35 223 1956 168 30 57 255 1957 265 29 53 347 1958 226 35 56 317 1959 222 30 44 296 1960 294 24 83 401 1961 339 30 61 430 1962 356 58 414 1963 338 27 365 1964 376 45 421 1965 324 50 374 1966 312 20 332 1967 429 26 455 1968 290 16 306 1969 261 7 268 1970 158 25 183 1971 242 32 9 283 1972 327 31 12 370 1973 260 52 13 325 1974 388 39 9 436 1975 381 55 16 16 9-9 468 1976 367 34 11 21 2 155-155 435 1977 400 91 13 8 1 276-276 513 1978 336 141 9 9 141-141 495 1979 301 57 8 6 1 84-84 373 1980 228 73 9 12 2 5-5 324 1981 199 59 7 16 1 282 1982 147 52 4 8 1 1-1 212 1983 180 70 11 15 31-31 276 1984 235 76 13 13 54-54 337 1985 275 102 19 1 + 132-132 397 1986 456 158 26 1 2 109-109 643 1987 564 137 19 2 70-70 722 1988 540 138 24 4 706 1989 578 217 21 7 1 824 1990 464 128 29-2 +427 1050 1991 746 216 38 + +11 1011 1 1992 856 372 54 +12 1294 1 1993 1016 355 68 9-9 1439 1 1994 890 296 12 4-4 1198 1995 850 382 65 6-6 1297 1996 784 203 57 612-597 1059 1997 560 200 52 2 814 1998 367 145 90 3 605 1999 431 158 45 3 637 2000 399 320 34 11-132 2 633 2 2001 1 249 286 25-103 2 455 2 2002 360 177 15 11 +281 3 844 2003 195 77 11 17 +301 3 602 2004 249 109 16 18 +392 3 784 2005 531 132 30 34 Norway +145 3 727 2006 521 114 38 43 9 4 729 2007 366 81 45 39 9 541 2008 361 102 34 35 7 3 544 1 Considerable non-reporting assumed for the period 1991 1993. 2 Catches from Skagerrak were reduced by these amounts because of misreporting from the North Sea. The subtracted amount has been added to the North Sea sole catches. Total landings for these years in IIIA has been reduced by the amount of misreporting. 3 Assuming misreporting rates at 50, 100, 100, and 20% in 2002-2005, respectively. ICES Advice 2009, Book 6 97

Table 6.4.9.3 Sole in Division IIIa. Summary of the assessment. Year Recruitment SSB Landings Mean F Age 1 Ages 4-8 thousands tonnes tonnes 1984 2756 884 337 0.4618 1985 6259 1131 397 0.2509 1986 5238 2011 643 0.3895 1987 5092 2177 722 0.6081 1988 3593 2367 706 0.3585 1989 5724 2408 824 0.4224 1990 7212 2902 1050 0.3449 1991 7224 3296 1011 0.4135 1992 9092 4770 1294 0.4268 1993 6659 4568 1439 0.4717 1994 3541 4593 1198 0.3663 1995 3355 3729 1297 0.5664 1996 2209 3488 1059 0.3497 1997 1133 2862 814 0.3886 1998 4571 2278 605 0.3194 1999 3246 2398 638 0.3228 2000 2389 2447 633 0.3257 2001 3540 2422 455 0.2016 2002 5252 2779 845 0.3583 2003 5033 2966 600 0.3148 2004 5283 3422 782 0.3567 2005 2320 3485 878 0.3206 2006 2000 2968 729 0.3079 2007 1861 2598 542 0.2243 2008 3728 2151 543 0.2779 2009 3098* 2370 Average 4285 2826 802 0.3660 * Recruitment in 2009 is Geometric Mean (1994-2006). 98 ICES Advice 2009, Book 6

6.4.10 Sole in Subarea IV (North Sea) State of the stock Spawning biomass in relation to precautionary limits Fishing mortality in relation to precautionary limits Fishing mortality in relation to high longterm yield Fishing mortality in relation to agreed target Comment Full reproductive capacity Harvested sustainably Appropriate Above target Based on the most recent estimate of SSB (in 2009) and fishing mortality (in 2008), ICES classifies the stock as having full reproductive capacity and is being harvested sustainably. SSB has fluctuated around the precautionary reference points for the last decade, but has increased since 2008 owing to a large incoming 2005 year class and reduced fishing mortality. Fishing mortality has shown a declining trend since 1995 and is currently estimated to be below F pa. The assessment suggests that the 2006 year class was below average, and 2007 average. Management objectives The EC has adopted a management plan for flatfish in the North Sea in June 2007 (Council Regulation (EC) No. 676/2007, see 6.4.10 Annex). This plan has two stages. The first stage aims at an annual 10% reduction of fishing mortality in relation to the fishing mortality estimated for the preceding year until an F of 0.2 is reached, with a maximum change in TAC of 15% until the precautionary reference points are reached for both sole and plaice for two successive years. ICES interprets the F for the preceding year as the estimate of F for the year in which the assessment is carried out. The basis for this F estimate in the preceding year will be a constant application of the procedure used by ICES in 2007. In the second stage, the management plan aims for exploitation at F = 0.2. ICES has evaluated the long-term management plan and concluded that it leads on average to a low risk of B < B lim within the next 10 years. ICES concludes that for sole the management plan can be provisionally accepted as precautionary. According to the evaluation the agreed management plan can be provisionally accepted as precautionary for sole and could be used as a basis for the management of the stock in the short term. Additional evaluations of the management plan are necessary to take into account retrospective bias of the assessment and the sporadic nature of recruitment. Reference points Type Value Technical basis B lim 25,000 t B loss Precautionary B pa 35,000 t B pa 1.4 *B lim approach F lim Not defined F pa 0.40 F pa = 0.4 implies B eq > B pa and P(SSB MT < B pa ) < 10%. Targets F mgt 0.2 EU management plan (unchanged since 1998, target added in 2008) Yield and spawning biomass per Recruit F-reference points (2009): Fish Mort Yield/R SSB/R Ages 2 6 Average last 3 years 0.39 0.17 0.36 F max * 0.59 0.17 0.24 F 0.1 0.11 0.14 1.02 F med 0.32 0.17 0.43 *Poorly defined Candidates for reference points consistent with high long-term yields and a low risk of depleting the productive potential of the stock are in the range of F 0.1 F pa. ICES Advice 2009, Book 6 99

Single-stock exploitation boundaries Considering the options below, ICES advises on the basis of exploitation boundaries in relation to the agreed management plan that landings should be less that 14 100 t in 2010. Exploitation boundaries in relation to the agreed management plan According to the management plan adopted by the EC in 2007, fishing mortality in 2010 should be reduced by 10% compared to the fishing mortality estimated for the preceding year (F2008=F2009=0.34) with the constraints that the TAC should not be changed by more than 15%. A 10% reduction in fishing mortality corresponds to an F of 0.304 and landings of 14 100t in 2010 which is within the 15% change (TAC 2009=14 000t). Exploitation boundaries in relation to high long-term yield, low risk of depletion of production potential and considering ecosystem effects The current fishing mortality is within the range that is expected to lead to high long-term yields and low risk to stock depletion. Exploitation boundaries in relation to precautionary limits The fishing mortality in 2010 should be no more than F pa, corresponding to landings of less than 17 800 t.. Short-term implications Outlook for 2010 Basis: F(2009) = F sq = mean F(2006 2008) scaled to 2008 = 0.34 ; R(2009) = GM (1957 2006) =93.800 mln; SSB(2010) = 37.660 ; landings (2009) = 15.140 Rationale Landings F SSB %SSB %TAC Basis (2010) (2010) (2011) change 1) change 2) Zero catch 0 F=0 0 53 +41% -100% High long-term yield 5.6 F0.1 0.11 48 +27% -60% Management plan 14.1 Fsq*0.9 0.3 40 +5% +1% 4.4 Fsq*0.25 0.08 49 +30% -69% Status quo 8.4 Fsq*0.5 0.17 45 +20% -40% 9.8 Fsq*0.59 0.2 44 +16% -30% 11.9 Fsq*0.74 0.25 42 +11% -15% 15.5 Fsq*1 0.34 38 +2% +10% 16.1 Fsq*1.05 0.36 38 0 +15% 17.8 Fsq*1.18 = Fpa 0.4 36-4% +27% 18.6 Fsq*1.25 0.42 35-6% +33% 21.4 Fsq*1.5 0.51 33-13% +53% 24 Fsq*1.75 0.59 30-20% +72% 26.5 Fsq*2 0.68 28-26% +89% Weights in 000 t. Shaded scenarios are not considered consistent with the precautionary approach. 1) SSB(2011) relative to SSB(2010). 2) Calculated landings (2010) relative to TAC 2009 (14 000 t). Management considerations Sole are mainly caught in a mixed beam trawl fishery with plaice and other flatfish using 80 mm mesh in the southern North Sea. The minimum mesh size in the mixed beam trawl fishery in the southern North Sea means that large numbers of undersized plaice and cod are discarded. There are indications that in recent years sole discarding has taken place. Measures to reduce discarding in the mixed beam trawl fishery would greatly benefit these stocks. An increase in the minimum landing size of sole could provide an incentive to fish with larger mesh sizes and would therefore mean a reduction in the discarding of plaice. The minimum landing size of North Sea sole is 24 cm. An increased mesh size in the fishery would reduce the catch of undersized plaice and cod, but would also result in a short-term loss of marketable sole. 100 ICES Advice 2009, Book 6

For two succesive years, the stock has been classified within safe precautionary bounderies and thus fullfilled the 1 st phase of the management plan. The increase in SSB is mainly achieved by the strong 2005 year class. The main explanation for the reduction of fishing mortality seems to be a proper implementation of the current management plan complemented with a reduction of capacity in the beam trawl fleet and a limitation of fishing effort. Also high fuel prices have contributed to the decrease in fishing mortality. The peaks in the historical time-series of SSB of North Sea sole correspond with the occasional occurrence of strong year classes. Due to a high fishing mortality the SSB has declined during the nineties. The fishery opportunities and SSB are now dependent on incoming year classes and can therefore fluctuate considerably between years. The SSB and landings in recent years have been dominated by the 2001 and 2005 year classes. The predicted SSB in 2011 is still largely dependent on the above-average recruitment of the 2005 year class. ICES has developed a generic approach to evaluate whether new survey information that becomes available in September forms a basis to update the advice. If this is the case, ICES will publish new advice in November 2009. Management plan evaluation According to evaluation of the agreed management plan it can be provisionally accepted as precautionary for sole. Estimations of sole stock status appear to have a retrospective under-estimation of fishing mortality and over-estimation of SSB, which have resulted in forecast bias. The probability of successfully attaining the objectives of the first stage of the management plan is dependent on the assumption of a stock recruitment relationship, which is not well founded. The dynamics of the stock is driven by the sporadic strong year classes that lead to wide fluctuations in the SSB. Additional evaluations of the management plan are necessary to take into account retrospective bias of the assessment and the nature of recruitment to conclude on the precautionary nature of the plan in the long term. Impacts of fisheries on the ecosystem Currently the mixed plaice and sole fishery is dominated by bottom trawls, with bycatch of both commercial and noncommercial species and with physical impact on the seabed. Bottom trawling reduces biomass, production, and species richness. For the North Sea, an ecosystem model showed that the bottom trawl fleet reduced benthic biomass and production by 56% and 21%, respectively, compared with an un-fished situation (Hiddink et al., 2006; Hinz et al., 2008). Chronic fishing has caused a shift from communities dominated by relatively sessile, emergent, high biomass species to communities dominated by infaunal, smaller-bodied fauna (Kaiser et al., 2000). Within species, the size selectivity may lead to a shift in the age and size at maturation. For example, plaice and sole become mature at younger ages and at smaller sizes in recent years than in the past. There is a risk that this shift is a genetic fisheries-induced change (Grift et al., 2004; Mollet et al., 2007) Factors affecting the fisheries and the stock The effects of regulations Due to a range of factors such as TAC constraints on plaice, effort limitations, and increases in fuel prices, the fishing effort of the major fleets targeting sole has decreased since the mid-1990s and concentrated in the southern part of the North Sea. This is the area where a large part of the juvenile plaice in the North Sea is found. The combination of a change in fishing pattern and the spatial distribution of juvenile plaice has led to an apparent increase in discarding of plaice. The plaice box was established in 1989, and the area has been closed in all quarters since 1995. The closed area applies to vessels using towed gears, but vessels smaller than 300 HP are exempted from the regulation. The effectiveness of the plaice box has been evaluated by a STECF expert group which concluded that the proportion of undersized sole inside the plaice box did not change after the closure and remained stable at 60 70% (Grift et al., 2004). Changes in fishing technology and fishing patterns Due to a range of factors such as effort limitations, increases in fuel prices, and disproportionate changes in the TACs for the two main target species sole and plaice, the fishing effort of the major fleets has concentrated in the southern part of the North Sea. This is the area where many juvenile plaice are found. In addition, juvenile plaice has shown a more offshore distribution in recent years. The combination of a change in fishing pattern and the spatial distribution of juvenile plaice has lead to an increase in discarding of plaice. The technical efficiency has increased by about 2.8% per year in the sole fishery since 1990, which could have counteracted part of the decrease in effort (Rijnsdorp et al., 2006). ICES Advice 2009, Book 6 101

Impacts of the environment on the fish stocks There has been an overall increase in growth of North Sea sole, followed by a decline correlated with the temporal patterns in eutrophication, in particular the discharge of dissolved phosphates by the Rhine. The spatial distribution of juvenile and adult sole remains constant within the Plaice Box (Grift et al., 2004), following the removal of a large amount of effort. The proportion of undersized sole (<24 cm) did not change after closure and remained stable at a level of 60 70% (Grift et al., 2004). Different length groups showed different patterns in abundance. Sole of around 5 cm showed a decrease in abundance from 2000 onwards, while the groups of 10 and 15 cm seemed rather stable. The largest groups showed a declining trend in abundance, which had already set in years before the closure. Scientific basis Data and methods The stock assessment is based on an XSA assessment, calibrated with two survey indices and one commercial lpue index. Discards are not included in the assessment. Routine discard sampling since 2003 under the EU Data Collection Regulations indicates overall discarding of sole in the order of 10% in weight and discards are considered to be a minor bias to the assessment results. Uncertainties in assessment and forecast There are indications of recurring underestimation of fishing mortality and overestimation of abundance. A discrepancy between the trends in surveys and the commercial cpue is apparent in the the results of comparisons between survey and commercial time-series of information. The survey information indicates higer mortality rates and lower stock abundance, consistent with the more recent values to which the assessment estimates are revised each year. There are indications that discarding may have an impact on the assessment results Information from the fishing industry The North Sea Fisher s survey took place in 2008. A total of 195 responses were collected for sole. As in the 2007 survey, the beam trawl and gill net fishing groups indicated that sole were more abundant and the fishers felt that discarding had reduced slightly with respect to 2007. Of those that expressed an opinion on recruitment the majority considered it to be moderate or high. These observations are consistent with the assessment results. Comparison with previous assessment and advice The estimate of F for 2007 from the 2008 assessment was revised down by 5% in the 2009 assessment. The SSB estimate for 2007 increased 3% in the 2009 assessment. The revisions are different from retrospective bias in the assessment results previously. Fishing mortality in the intermediate year used in the 2009 forecast was the average F (2006-2008) scaled to F (2008). The basis for this forecast is different from the previous forecasts, where the average F over the final 3 years was used to counteract the retrospective change from year to year. The advice this year is based on the EU management plan, similar to last year. Sources of information Report of the Working Group on the Assessment of Demersal Stocks in the North Sea and Skagerrak, 6-12 May 2009 (ICES CM 2009/ACOM:10). Grift, R. E., Tulp, I., Clarke, L., Damm, U., McLay, A., Reeves, S., Vigneau, J., and Weber, W. 2004. Assessment of the ecological effects of the Plaice Box. Report of the European Commission Expert Working Group to evaluate the Shetland and Plaice boxes. Brussels. 121 pp. Hiddink, J. G., Jennings, S., Kaiser, M. J., Queirós, A. M., Duplisea, D. E, and Piet, G. J. 2006. Cumulative impacts of seabed trawl disturbance on benthic biomass, production, and species richness in different habitats. Canadian Journal of Fisheries and Aquatic Sciences, 63: 721 736. Hinz, H., Hiddink, J. G., Forde, J., and Kaiser, M. J. 2008. Large-scale responses of nematode communities to chronic otter-trawl disturbance. Canadian Journal of Fisheries and Aquatic Sciences, 65: 723 732. 102 ICES Advice 2009, Book 6

Kaiser, M. J., Ramsay, K., Richardson, C. A., Spence, F. E., and Brand, A. R. 2000. Chronic fishing disturbance has changed shelf sea benthic community structure. Journal of Animal Ecology, 69: 494 503. Rijnsdorp, A. D., Daan, N., and Dekker, W. 2006. Partial fishing mortality per fishing trip: a useful indicator of effective fishing effort in mixed demersal fisheries. ICES Journal of Marine Science, 63: 556 566. Table 6.4.10.1 Sole in Subarea IV (North Sea). Single stock exploitation boundaries (advice), management and landings. Year ICES Advice Single-stock exploitation boundaries Predicted catch corresponding to advice Predicted catch corresponding to single-stock Agreed TAC Official landings ICES landings 1987 Rebuild SSB to 40 000 t; TAC 11.0 14.0 13.8 17.4 1988 Increase SSB towards 50 000 t; TAC 11.0 14.0 13.4 21.6 1989 Increase SSB towards 50 000 t; TAC 14.0 14.0 14.5 21.8 1990 80% of F(88); TAC 25.0 25.0 26.5 35.1 1991 SSB>50 000 t ; TAC 27.0 27.0 27.6 33.5 1992 TAC 21.0 25.0 26 29.3 1993 no long-term gains in increased F 29.0 1 32.0 29.8 31.5 1994 no long-term gains in increased F 31.0 1 32.0 31.3 33 1995 no long-term gains in increased F 28.0 1 28.0 28.8 30.5 1996 Mixed fishery, link plaice advice 23.0 1 23.0 20.4 22.7 1997 <80% of F(95) 14.6 18.0 13.7 15 1998 75% of F(96) 18.1 19.1 19.7 20.9 1999 F<F pa (80% of F(97)) 20.3 22.0 22 23.5 2000 F< F pa <19.8 22.0 20.7 22.5 2001 F< F pa <17.7 19.0 16.4 19.9 2002 F<0.37 <14.3 16.0 16 16.9 2003 F< F pa <14.6 15.85 17.1 17.9 2004 2 F< F pa 2 <17.9 17.0 17.8 17.1 2005 F< F pa <17.3 18.6 15.6 16.4 2006 Keep SSB above B pa <11.9 17.67 11,9 12.6 2007 SSB above B pa <10.8 15.0 13.8 14.6 SSB above 2008 B pa <9.8 12.8 13.4 14.1 2009 Apply management plan <14.0 14.0 2010 Apply management plan <14.1 Weights in 000 t. 1 Catch status quo F. 2 Single-stock boundary and the exploitation of this stock should be conducted in the context of mixed fisheries protecting stocks outside safe biological limits. ICES Advice 2009, Book 6 103

Figure 6.4.10.1 Sole in Subarea IV (North Sea). Landings, fishing mortality, recruitment, and biomass (SSB). Predicted values are shaded. 104 ICES Advice 2009, Book 6

Stock - Recruitment 600 Recruitment (age 1) in millions 500 400 300 200 100 SSB-Rec. Blim Bpa 0 0 20 40 60 80 100 120 140 SSB in 1000 t Yield and Spawning Stock Biomass per Recruit 0.18 3 Yield (dashed line) 0.16 0.14 0.12 0.1 0.08 0.06 0.04 0.02 2.5 2 1.5 1 0.5 SSB (line) 0 0 0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 Fishing Mortality (ages 2-6) SSB in 1000 t 140 120 100 80 60 40 20 Precautionary Approach Plot Period 1957-2008 0 0.0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 Fishing Mortality (ages 2-6) F-SSB 2008 Fpa Blim Bpa Figure 6.4.10.2 Sole in Subarea IV (North Sea). Stock recruitment, yield, and precautionary approach. ICES Advice 2009, Book 6 105

Figure 6.4.10.3 Sole in Subarea IV (North Sea). Results of the North Sea Commission fishers survey 2008. Sol e i n Sub-area I V ( N ort h Sea) 100 90 SSB ('000 tonnes) 0.80 0.70 Fishing mortality: 2-6 500 450 Millions Recruitment. Age: 1 80 70 0.60 400 350 60 0.50 300 50 0.40 250 40 0.30 200 30 20 0.20 150 100 10 0.10 50 0 1990 1995 2000 2005 0.00 1990 1995 2000 2005 0 1990 1995 2000 2005 Figure 6.4.10.4 Sole in Subarea IV (North Sea). Historical performance of the assessments. 106 ICES Advice 2009, Book 6

Table 6.4.10.2 Sole in Subarea IV (North Sea). Nominal landings and landings as estimated by the Working Group (tonnes). Year Belgium Denmark France Germany Netherlands UK Other Total Unallocated WG TAC (E/W/NI) countries reported landings Total 1982 1900 524 686 266 17686 403 2 21467 112 21579 21000 1983 1740 730 332 619 16101 435 19957 4970 24927 20000 1984 1771 818 400 1034 14330 586 1 18940 7899 26839 20000 1985 2390 692 875 303 14897 774 3 19934 4314 24248 22000 1986 1833 443 296 155 9558 647 2 12934 5266 18200 20000 1987 1644 342 318 210 10635 676 4 13829 3539 17368 14000 1988 1199 616 487 452 9841 740 28 13363 8227 21590 14000 1989 1596 1020 312 864 9620 1033 50 14495 7311 21806 14000 1990 2389 1427 352 2296 18202 1614 263 26543 8577 35120 25000 1991 2977 1307 465 2107 18758 1723 271 27608 5905 33513 27000 1992 2058 1359 548 1880 18601 1281 277 26004 3337 29341 25000 1993 2783 1661 490 1379 22015 1149 298 29775 1716 31491 32000 1994 2935 1804 499 1744 22874 1137 298 31291 1711 33002 32000 1995 2624 1673 640 1564 20927 1040 312 28780 1687 30467 28000 1996 2555 1018 535 670 15344 848 229 21199 1452 22651 23000 1997 1519 689 99 510 10241 479 204 13741 1160 14901 18000 1998 1844 520 510 782 15198 549 339 19742 1126 20868 19100 1999 1919 828 1458 16283 645 501 21634 1841 23475 22000 2000 1806 1069 362 1280 15273 600 539 20929 1603 22532 22000 2001 1874 772 411 958 13345 597 394 18351 1593 19944 19000 2002 1437 644 266 759 12120 451 292 15969 976 16945 16000 2003 1605 703 728 749 12469 521 363 17138 782 17920 15850 2004 1477 808 655 949 12860 535 544 17828-681 17147 17000 2005 1374 831 676 756 10917 667 357 15579 776 16355 18600 2006 980 585 648 475 8299 910 11933 667 12600 17670 2007 955 413 401 458 10365 1203 5 13800 835 14635 15000 2008 1379 507 714 513 9456 851 15 13435 710 14145 12800 ICES Advice 2009, Book 6 107

Table 6.4.10.3 Sole in Subarea IV (North Sea). Summary of stock assessment. Year Recruitment SSB Landings Mean F Age 1 Ages 2-6 thousands tonnes tonnes 1957 128909 55107 12067 0.18 1958 128643 60919 14287 0.21 1959 488757 65580 13832 0.17 1960 61714 73398 18620 0.20 1961 99488 117099 23566 0.19 1962 22895 116830 26877 0.21 1963 20420 113628 26164 0.31 1964 539075 37127 11342 0.29 1965 121959 30029 17043 0.32 1966 39901 84243 33340 0.33 1967 75135 82958 33439 0.41 1968 99262 72306 33179 0.49 1969 50787 55267 27559 0.55 1970 137795 50680 19685 0.40 1971 42148 43742 23652 0.51 1972 76525 47437 21086 0.46 1973 104859 36775 19309 0.50 1974 109939 36110 17989 0.49 1975 40816 38365 20773 0.50 1976 113311 38944 17326 0.42 1977 140375 34623 18003 0.46 1978 47256 36195 20280 0.48 1979 11723 44954 22598 0.49 1980 151694 33584 15807 0.45 1981 149346 22921 15403 0.50 1982 152751 32855 21579 0.54 1983 142179 39956 24927 0.49 1984 70791 43464 26839 0.61 1985 80833 41082 24248 0.60 1986 159654 34554 18201 0.57 1987 72553 29658 17368 0.49 1988 454627 38765 21590 0.57 1989 108296 34075 21805 0.45 1990 177757 89643 35120 0.45 1991 70476 77479 33513 0.45 1992 354171 76772 29341 0.43 1993 69289 54752 31491 0.51 1994 57057 74337 33002 0.56 1995 96104 58934 30467 0.53 1996 49508 38310 22651 0.70 1997 271749 28071 14901 0.60 1998 114161 20882 20868 0.64 1999 82581 41918 23475 0.57 2000 123824 39217 22641 0.60 2001 63480 30762 19944 0.57 2002 187821 31412 16945 0.56 2003 85663 25758 17920 0.57 2004 46679 38402 18757 0.50 2005 49955 33520 16355 0.55 2006 221770 25778 12594 0.41 2007 60383 19585 14635 0.41 2008 90949 40676 14144 0.34 2009 93786* 37670 Average 124747 49191 21703 0.46 * GM (1957 2006) 108 ICES Advice 2009, Book 6

6.4.10 Annex Extract from Council Regulation (EC) No 676/2007 of 11 June 2007 establishing a multiannual plan for fisheries exploiting stocks of plaice and sole in the North Sea Article 8 Procedure for setting the TAC for sole: 1) The Council shall adopt a TAC for sole at that level of catches which, according to a scientific evaluation carried out by STECF is the higher of: a) that TAC the application of which will result in the level of fishing mortality rate of 0,2 on ages two to six years in its year of application; b) that TAC the application of which will result in a 10 % reduction in the fishing mortality rate in its year of application compared to the fishing mortality rate estimated for the preceding year. 2) Where the application of paragraph 1 would result in a TAC which exceeds the TAC of the preceding year by more than 15 %, the Council shall adopt a TAC which is 15 % greater than the TAC of that year. 3) Where the application of paragraph 1 would result in a TAC which is more than 15 % less than the TAC of the preceding year, the Council shall adopt a TAC which is 15 % less than the TAC of that year. Under the consideration nr 3 in the Council Regulation (EC) No 676/2007 of 11 June 2007 establishing a multiannual plan for fisheries exploiting stocks of plaice and sole in the North Sea it is stated: The Scientific, Technical and Economic Committee for Fisheries (STECF) has advised that the precautionary biomass for the stock of sole in the North Sea should be 35 000 tonnes. ICES Advice 2009, Book 6 109

6.4.11 Sole in Division VIId (Eastern Channel) State of the stock Spawning biomass in relation to precautionary limits Full reproductive capacity Fishing mortality in relation to precautionary limits Fishing mortality in relation to high longterm yield Increased risk Overfished NA Fishing mortality in relation to agreed management targets Comment Based on the most recent estimate of SSB (in 2009) and fishing mortality (in 2008), ICES classifies the stock as having full reproductive capacity and at risk of being harvested unsustainably. The spawning-stock biomass has been fluctuating around a mean of about 10 000 t since 1982, and has been above B pa since 2002. The fishing mortality has decreased since 1999 and has been around F pa from 2001 until 2005. In the last 3 years fishing mortality has increased and fluctuated between F pa and F lim. The 2001, 2004 and 2005 year classes were the three highest since 1990. The 2007 year class is the weakest in the time-series. Management objectives No explicit management objectives are set for this stock. Reference points Precautionary approach Type Value Technical basis B lim Not defined Poor biological basis for definition B pa 8000 t This is the lowest observed biomass at which there is no indication of impaired recruitment. Smoothed B loss F lim 0.55 F loss, but poorly defined; analogy to North Sea and setting of 1.4 F pa = 0.55. This is a fishing mortality at or above which the stock has shown continued decline. F pa 0.4 Between F med and 5th percentile of F loss ; SSB>B pa and probability (SSB mt <B pa ), 10%: 0.4. Targets F y Not defined (unchanged since 1998) Yield and spawning biomass per Recruit F-reference points (2009): Fish Mort Yield/R SSB/R Ages 3-8 Average last 3 years 0.47 0.16 0.36 Fmax 0.27 0.17 0.64 F0.1 0.10 0.15 1.44 Fmed 0.41 0.17 0.43 Candidates for reference points which are consistent with high long-term yields and a low risk of depleting the productive potential of the stock are in the range of F 0.1 -F max. Single-stock exploitation boundaries Considering the options below, ICES advises on the basis of precautionary limits that fishing mortality in 2010 should be no more than F pa corresponding to landings of less than 3190 t in 2010 Exploitation boundaries in relation to high long-term yield, low risk of depletion of production potential, and considering ecosystem effects Fishing mortality in 2008 is estimated at 0.45, above the range that would lead to high long-term yields and low risk of stock depletion. 110 ICES Advice 2009, Book 6

Exploitation boundaries in relation to precautionary limits The fishing mortality in 2010 should be below F pa corresponding to landings less than 3190 t in 2010, which is expected to keep SSB above B pa in 2011. Short-term implications Outlook for 2010 Basis: F(2009) = Fsq = mean F(06-08) = 0.47; R(2009) = GM 1982-2006 = 23.6 million; SSB(2009) = 10.6 ; SSB(2010) = 7.91; landings (2009) = 4.19 Rationale Landings %SSB %TAC (2010) 1) Basis F(2010) SSB(2011) change 2) Change 3) Zero catch 0.00 F=0 0.00 11.8 49% -100% High long term yield 2.27 F(long term yield) 0.27 9.3 18% -57% 2.38 Fsq *0.6 0.28 9.2 17% -55% 2.72 Fsq *0.7 0.33 8.9 12% -49% 3.04 Fsq *0.8 0.38 8.5 8% -42% Status quo 3.19 Fsq *0.85 0.40 8.4 6% -40% 3.35 Fsq *0.9 0.42 8.2 3% -36% 3.65 Fsq *1 0.47 7.9-1% -31% 3.94 Fsq *1.1 0.52 7.6-4% -25% 4.22 Fsq *1.2 0.56 7.3-8% -20% 4.48 Fsq *1.31 0.62 7.0-12% -15% Weights in '000 t. Shaded scenarios are considered not consistent with precautionary approach. 1) It is assumed that the TAC will be implemented and that the landings in 2010 therefore correspond to the TAC. 2) SSB 2011 relative to SSB 2010. 3) Landings 2010 relative to TAC 2009. Management considerations Sole is mainly caught in beam trawl fisheries with plaice or in mixed demersal fisheries using otter trawls. There is also a directed fishery during parts of the year by inshore trawlers and netters on the English and French coasts. Due to the minimum mesh size (80 mm) in the mixed beam trawl fishery, a large number of (undersized) plaice are discarded. The 80 mm mesh size is not matched to the minimum landing size of plaice. Measures to reduce discarding of plaice in the sole fishery would greatly benefit the plaice stock and future yields. Mesh enlargement would reduce the catch of undersized plaice, but would also result in short-term loss of marketable sole. An increase in the minimum landing size of sole could provide an incentive to fish with larger mesh sizes and therefore mean a reduction in the discarding of plaice. Under-reporting of catches and misreporting of sole into Division VIId from Division VIIe is thought to be significant and should be avoided. This will also improve the quality of the assessment. Factors affecting the fisheries and the stock There are five main commercial fleets fishing for sole in Division VIId. Belgian and English offshore beam trawlers (> 300 HP) fish mainly for sole, but can switch to scallops or move to adjacent areas. French offshore trawlers target roundfish and take sole as bycatch. Numerous inshore vessels (under 10 m) on the English and French coasts target sole in the spring and autumn, using mainly fixed nets. The inshore vessels take half the reported landings and sole forms their main source of income. Effort from the beam trawl fleet can change considerably depending on whether the fleet moves to other areas or directs effort at other species such as scallops and cuttlefish. Regulations and their effects The minimum landing size for sole is 24 cm. Demersal gears are permitted to catch sole with mesh size 80 mm for beam and otter trawling. For static gear the minimum mesh size is 120 mm, with exceptions for trammelnets (100 mm) and static gear targeting red mullet and sea bass (90 mm). In previous years, effort from the beam trawl fleet has not been restricted. The new EU Council Regulation (EC) N 43/2009 does not reduce the effort for this fleet. ICES Advice 2009, Book 6 111

Changes in fishing technology and fishing patterns Effort for the Belgian beam trawl fleet increased to the highest level in 2007. This was mainly due to the unrestrictive days-at-sea EU regulation in ICES Subdivision VIId from 2006 until 2008. Impact of fisheries on the environment Currently the sole fishery is dominated by bottom trawls, with bycatch of both commercial (for instance plaice) and non-commercial species and physical impact on the seabed. Chronic fishing with bottom trawls has caused a shift from communities dominated by relatively sessile, emergent, high biomass species to communities dominated by infaunal, smaller-bodied fauna (Kaiser et al., 2000). Scientific basis Data and methods The XSA assessment, which was benchmarked in 2009, is based on landings data, two commercial cpue indices, and three research-vessel survey indices. Discards are not included in the assessment. Routine discard sampling since 2003 under the EU Data Collection Regulations indicates overall discarding of sole in the order of 5% in weight and discards are therefore considered to be a minor bias to the assessment results. Uncertainties in assessment and forecast Under-reporting from the inshore fleets and misreporting into Division VIId by beam trawlers fishing in VIIe is thought to be significant. Historical landings have been adjusted for misreporting between the Eastern and Western Channel since 1986. In recent years there have been substantial changes in the estimates of recruitment which impact on the forecast. Comparison with previous assessment and advice In 2009 the Young fish survey was separated into two components due to the cessation of the UK component in 2007. The current assessment has revised the value of SSB in 2007 and 2008 downward by 14% and 10% respectively (Figure 6.4.11.3). The estimate of fishing mortality in 2007 was revised upwards by 26%. Past recruitment estimates were subject to considerable annual revision. The strong 2004 year class has been confirmed by the latest four assessments. The weak year class 2006 has been revised upward in this year s assessment by 78% and the assumed GM for the incoming 2007 year class in last year s assessment has now been revised downward by 62%.. The advice basis is the same as last year. The advice for 2010 is considerably lower than last year because of a downward revision of estimated stock size and poor incoming recruitment. Sources of information Report of the Working Group on the Assessment of Demersal Stocks in the North Sea and Skagerrak, 6-12 May 2009 (ICES CM 2009/ACOM:10). ICES. 2009. Report of the Benchmark and Data Compilation Workshop for Flatfish (WKFLAT 2009), 6 13 February 2009, Copenhagen, Denmark. ICES CM 2009/ACOM:31. Kaiser, M. J., Ramsay, K., Richardson, C. A., Spence, F. E., and Brand, A. R. 2000. Chronic fishing disturbance has changed shelf sea benthic community structure. Journal of Animal Ecology, 69: 494 503. 112 ICES Advice 2009, Book 6

Table 6.4.11.3 Year ICES advice Sole in Division VIId (Eastern Channel), Single stock exploitation boundaries (advice), management and landings. Single-Stock Exploitation Boundaries Predicted catch corresp. to advice Predicted catch corresp. to Single- Stock Exploitation Boundaries Agreed TAC Official landings ICES landings 1987 Precautionary TAC 3.1 3.85 3.8 4.8 1988 Status quo (Shot) TAC 3.4 3.85 3.3 3.9 1989 Status quo (Shot) TAC 3.8 3.85 2.9 3.8 1990 No effort increase; TAC 3.7 3.85 3.0 3.6 1991 Status quo F; TAC 3.4 3.85 3.8 4.4 1992 TAC 2.7 3.5 3.8 4.1 1993 70% of F(91)~2 800 t 2.8 3.2 3.8 4.3 1994 Reduce F <3.8 3.8 4.0 4.4 1995 No increase in F 3.8 3.8 3.7 4.4 1996 No long-term gain in 4.7 3.5 4.1 4.8 increasing F 1997 No advice - 5.23 3.9 4.8 1998 No increase in effort 4.5 5.23 3.0 3.4 1999 Reduce F to F pa 3.8 4.7 3.9 4.1 2000 F < F pa <3.9 4.1 3.8 3.5 2001 F < F pa <4.7 4.6 4.6 4.0 2002 F < F pa <5.2 5.2 5.4 4.7 2003 F < F pa <5.4 5.4 6.2 5.0 2004 1) F < F pa 1) <5.9 5.9 5.7 4.8 2005 1) F < F pa 1) <5.7 5.7 4.6 4.4 2006 1) F < F pa 1) <5.7 5.72 4.8 4.8 2007 1) F < F pa 1) <6.44 6.22 5.3 5.2 2008 1) F < F pa 1) <6.59 6.59 4.4 4.5 2009 1) F < F pa 1) <4.38 5.274 2010 1) F < F pa 1) <3.19 Weights in 000 t. 1) Single-stock boundary and the exploitation of this stock should be conducted in the context of mixed fisheries. ICES Advice 2009, Book 6 113

Landings 6 Landings in 1000 t 5 4 3 2 1 0 1982 1987 1992 1997 2002 2007 Fishing Mortality F(ages 3-8) 0.7 0.6 0.5 0.4 0.3 0.2 0.1 0.0 1982 1987 1992 1997 2002 2007 F Flim Fpa Recruitment (age 1) Recruitment in millions 50 45 40 35 30 25 20 15 10 5 0 1982 1987 1992 1997 2002 2007 Spawning Stock Biomass SSB in 1000 t 14 12 10 8 6 4 2 0 1982 1987 1992 1997 2002 2007 SSB Bpa Shaded recruitment: GM 1982-2006 Figure 6.4.11.1 Sole in Division VIId (Eastern Channel). Landings, fishing mortality, recruitment, and SSB. 114 ICES Advice 2009, Book 6

Stock - Recruitment Recruitment (age 1) in millions 50 45 40 35 30 25 20 15 10 5 0 0 5 10 15 SSB in 1000 t SSB-Rec. Bpa Yield and Spawning Stock Biomass per Recruit Yield (dashed line) 0.18 0.16 0.14 0.12 0.1 0.08 0.06 0.04 0.02 0 0 0.2 0.4 0.6 0.8 1 Fishing Mortality (ages 3-8) 4 3.5 3 2.5 2 1.5 1 0.5 0 SSB (line) SSB in 1000 t 14 12 10 8 6 4 2 Precautionary Approach Plot Period 1982-2008 0 0.0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 Fishing Mortality (ages 3-8) F-SSB 2008 Flim Fpa Bpa Figure 6.4.11.2 Sole in Division VIId (Eastern Channel). Stock recruitment, Yield-per-recruit, and precautionary approach plot. ICES Advice 2009, Book 6 115

18 SSB ('000 tonnes) 0.70 Fishing mortality: 3-8 70 Recruitment. Age: 1 16 0.60 Millions 60 14 12 0.50 50 10 0.40 40 8 0.30 30 6 4 0.20 20 2 0.10 10 0 1990 1995 2000 2005 0.00 1990 1995 2000 2005 0 1990 1995 2000 2005 Figure 6.4.11.3 Sole in Division VIId (Eastern Channel). Historical performance of the assessments. Note: some assessments have been indicative of trends only. 116 ICES Advice 2009, Book 6

Table 6.4.11.2 Sole in Division VIId (Eastern Channel). Nominal landings (tonnes) as officially reported to ICES and used by the Working Group. Total used TAC Year Belgium France UK(E+W) others reported Unallocated* by WG 1974 159 383 309 3 854 30 884 1975 132 464 244 1 841 41 882 1976 203 599 404. 1206 99 1305 1977 225 737 315. 1277 58 1335 1978 241 782 366. 1389 200 1589 1979 311 1129 402. 1842 373 2215 1980 302 1075 159. 1536 387 1923 1981 464 1513 160. 2137 340 2477 1982 525 1828 317 4 2674 516 3190 1983 502 1120 419. 2041 1417 3458 1984 592 1309 505. 2406 1169 3575 1985 568 2545 520. 3633 204 3837 1986 858 1528 551. 2937 995 3932 1987 1100 2086 655. 3841 950 4791 3850 1988 667 2057 578. 3302 551 3853 3850 1989 646 1610 689. 2945 860 3805 3850 1990 996 1255 785. 3036 611 3647 3850 1991 904 2054 826. 3784 567 4351 3850 1992 891 2187 706 10 3794 278 4072 3500 1993 917 2322 610 13 3862 437 4299 3200 1994 940 2382 701 14 4037 346 4383 3800 1995 817 2248 669 9 3743 677 4420 3800 1996 899 2322 877. 4098 699 4797 3500 1997 1306 1702 933. 3941 823 4764 5230 1998 541 1703 803. 3047 316 3363 5230 1999 880 2251 769. 3900 235 4135 4700 2000 1021 2190 621. 3832-356 3476 4100 2001 1313 2482 822. 4617-592 4025 4600 2002 1643 2780 976. 5399-666 4733 5200 2003 1657 3475 1114 1 6247-1209 5038 5400 2004 1485 3070 1112. 5667-841 4826 5900 2005 1221 2832 567. 4620-236 4384 5700 2006 1547 2627 678. 4852-18 4834 5720 2007 1530 2968 801 1 5300-134 5166 6220 2008 1367 2284 ** 715. 4366 144 4510 6593 * Unallocated mainly due misreporting ** Preliminary ICES Advice 2009, Book 6 117

Table 6.4.11.3 Sole in Division VIId (Eastern Channel), summary of the assessment. Year Recruitment SSB Landings Mean F Age 1 Ages 3-8 thousands tonnes tonnes 1982 12725 7813 3190 0.355 1983 21324 9576 3458 0.407 1984 21514 8983 3575 0.432 1985 12913 9979 3837 0.337 1986 25731 10584 3932 0.392 1987 10975 8987 4791 0.590 1988 25798 10139 3853 0.429 1989 16807 8435 3805 0.566 1990 44246 9624 3647 0.380 1991 34847 8774 4351 0.453 1992 33639 11194 4072 0.371 1993 16773 13156 4299 0.301 1994 26557 12558 4383 0.354 1995 19420 11110 4420 0.365 1996 18912 12148 4797 0.474 1997 27767 10551 4764 0.592 1998 17985 8114 3363 0.456 1999 26257 9040 4135 0.548 2000 30990 8512 3476 0.443 2001 26119 7616 4025 0.396 2002 46812 8489 4733 0.378 2003 20282 10270 5038 0.377 2004 18965 11343 4826 0.406 2005 38702 11270 4383 0.392 2006 37184 9679 4833 0.454 2007 14773 10929 5166 0.512 2008 9003 12762 4510 0.453 2009 23623* 10607 Average 24309 10080 4210 0.430 * Recruitment 2009: GM 1982-2006 118 ICES Advice 2009, Book 6

6.4.12 Saithe in Subarea IV (North Sea), Division IIIa (Skagerrak), and Subarea VI (West of Scotland and Rockall) State of the stock Spawning biomass in relation to precautionary limits Full reproductive capacity Fishing mortality in relation to precautionary limits Harvested sustainably Fishing mortality in relation to high longterm yield Appropriate Fishing mortality in relation to agreed target Appropriate Comment Based on the most recent estimates of SSB (in 2009) and fishing mortality (in 2008), ICES classifies the stock as having full reproductive capacity and being harvested sustainably. SSB is estimated to have been above B pa since 2001. From 2001 onwards, F has been at or below the target fishing mortality of 0.3. Management objectives The agreed EU Norway management plan (Annex 6.4.12) includes: 1) Maintain the SSB above 106 000 t, and 2) exploitation at F = 0.3 when the stock is above B pa. The management plan was evaluated by ICES in 2008 (ICES Advice 2008, Book 6, Section 6.3.3.3), and the management plan is considered by ICES to be consistent with the precautionary approach in the short term (< 5 years). Reference points Precautionary approach Type Value Technical basis B lim 106 000 t B loss = 106 000 t (estimated in 1998). B pa 200 000 t affords a high probability of maintaining SSB above B lim. F lim 0.6 F loss the fishing mortality estimated to lead to stock falling below B lim in the long term. F pa 0.4 implies that B eq > B pa and P(SSB MT < B pa ) < 10%. Targets F mgt 0.3 EU-Norway management plan (unchanged since 1998) Yield and spawning biomass per Recruit F-reference points (2009): Fish Mort Yield/R SSB/R Ages 3-6 Average last 3 years 0.29 0.82 1.81 Fmax 0.32 0.82 1.55 F0.1 0.14 0.74 3.87 Fmed 0.36 0.82 1.34 HCR evaluation has shown that candidates for reference points consistent with high long-term yields and a low risk of depleting the productive potential of the stock are around F = 0.3. Single-stock exploitation boundaries Considering the options below, ICES advises on the basis of the agreed management plan that the landings should be no more than 118 000 t in 2010. Exploitation boundaries in relation to existing management plans At the present SSB level, F should be no more than 0.3 to be in accordance with the management plan. This would give a 24% reduction in the TAC. However, there is a 15% TAC constraint when the stock is above B pa and applying this corresponds to landings of 118 000 t in 2010. ICES Advice 2009, Book 6 119

Exploitation boundaries in relation to high long-term yield, low risk of depletion of production potential, and considering ecosystem effects The current fishing mortality (2006-2008 average) is estimated at 0.29, which is close to the management plan target rate expected to lead to high long-term yields (F = 0.3). Exploitation boundaries in relation to precautionary limits An increase of F to 0.39 is possible while keeping SSB above B pa in 2011. This corresponds to landings of less than 132 000 t in 2010. Short-term implications Outlook for 2010 Basis: F(2009) = F06 08 = 0.287 ; R09 11 = GM88 06 = 122 ; SSB(2010) = 235 ; landings (2009) = 110. Rationale landings 2010 landings IIIa&IV 2010 1) landings VI 2010 1) Basis F 2010 SSB 2011 %SSB change 2) % TAC change 3) Zero catch 0 0 0 F=0 0 320 36-100 Management 0.85*TAC09 118 107.1 11.1 plan (1.19*F sq ) 0.34 212-9 -15 Precautionary B 132 119.6 12.4 pa approach (1.37*F sq ) 0.39 200-15 -5 Status quo 39 35.6 3.7 0.35*F sq 0.10 283 21-72 57 51.9 5.4 0.52*F sq 0.15 267 14-59 74 67.4 7.0 0.70*F sq 0.20 251 7-46 102 92.2 9.6 F sq 0.29 227-3 -27 106 95.9 9.9 F MPtarget 0.30 223-5 -24 110 100.0 10.4 1.1*F sq 0.32 219-7 -21 119 107.4 11.1 1.2*F sq 0.34 212-10 -15 127 114.7 11.9 1.3*F sq 0.37 205-13 -9 Weights in 000 t. 1) Landings split according to the average in 1993 1998, i.e. 90.6% in Subarea IV and Division IIIa and 9.4% in Subarea VI. 2) SSB 2011 relative to SSB 2010. 3) Landings 2010 relative to TAC 2009. Management considerations The ICES advice applies to saithe in the three areas; Division IIIa, and Subareas IV and VI. Natural fluctuations in recruitment will result in a reduction of SSB to around B pa over the next few years. This is likely to lead to a decline in TAC advice. Following the management plan should provide an appropriate response. The reported landings have been lower than the TACs during the past seven years. Information from fishers indicates that this is due to very low prices for saithe combined with high fuel prices. However, there are also claims that the abundance of saithe has been reduced in the most recent years. By-catch of other demersal fish species occurs in some trawl fishery for saithe. Saithe is also taken as unintentional bycatch in other fisheries, and discards may occur if the vessels do not have a saithe quota. Impacts of fisheries on the ecosystems The effect on the bentic invertebrate community in the northern North Sea from all otter trawling is estimated to represent an annual mortality of approximately 25% of the standing-crop biomass.the MAFCONS and STECF dataset suggests that otter trawl effort directed at fish has declined since 1999 (Greenstreet et al., 2007). 120 ICES Advice 2009, Book 6

Factors affecting the fisheries and the stock Regulations and their effects In January 2002 the minimum mesh size (in bottom trawls for human consumption) was changed from 100 to 110 mm in EU waters and from 100 to 120 mm in Norwegian waters (the minimum mesh size for Norwegian vessels was set to 120 mm in both Norwegian and EU waters). In 2003 the mesh sizes were harmonized to 120 mm with the exception of the targeted saithe fishery (less than 3% cod bycatch), which remains at 110 mm. These variations might have contributed to changes in the exploitation pattern. Impacts of the environment on the fish stock A decrease in the mean weight-at-age has been observed in the past eleven years, but there is insufficient information to establish whether these reductions are linked to changes in the environment. The effects of a possible further decline in growth rates needs attention. There is no indication that the observed decline in weight-at-age is density dependent. Scientific basis Data and methods The stock is assessed using an age-based model (XSA), calibrated by two commercial cpue series and two survey indices. There are no discard estimates for the majority of this fishery. Discarding of saithe occurs in the non-targeted fisheries, but the level of discard is considered to be small compared to the total catch of saithe. Information from the fishing industry The reported landings in the last years have been lower than the TACs. Information from fishers indicates that very low prices on saithe, coupled with high fuel prices, are causing these reductions in targeted fisheries. Uncertainties in assessment and forecast The major uncertainty is the lack of information on year-class strength for ages 1 3. Therefore, IMR in Bergen, Norway began an acoustic survey along the western coast of Norway in 2006 to measure the relative abundance of saithe between 2 and 4 years old (when the saithe is distributed along the coast). However, the Norwegian acoustic survey will not be conducted in 2009. Another important problem with this assessment is the necessity to use commercial cpue for tuning as the survey series only contains usable information for ages 3-6. Since recruitment at age 3 tends to be poorly estimated in the XSA, the size of the 2005 year class is uncertain. Only very large relative errors will make a large impact on the forecast. Comparison with previous assessment and advice Compared to last years assessment, SSB in 2008 has been revised downwards by 14% and F in 2007 has been revised upwards by 6%. Recruitment in 2007 has been estimated 21% lower in this years assessment. The basis of the advice is unchanged. Sources of information Report of the Working Group on the Assessment of Demersal Stocks in the North Sea and Skagerrak, 6-12 May 2009 (ICES CM 2009/ACFM:10). Report of the Working Group on the Assessment of Demersal Stocks in the North Sea and Skagerrak, 6-12 May 2009 (ICES CM 2009/ACOM:10). ICES. 2008. Norway and EC request on management plan for saithe in the North Sea and West of Scotland. ICES Advice, 2008. Book 6. Greenstreet, S. P. R., Robinson, L. A., Piet, G. J., Craeymeersch, J., Callaway, R., Reiss, H., Ehrich, S., et al. 2007. The ecological disturbance caused by fishing in the North Sea. FRS Collaborative Report, 04/07. 169 pp. STECF. 2007. Report of the First and Fourth meeting of the Subgroup on Review of Stocks (SGRST-05-01 and SGRST-05-04) of STECF, Evaluation of the Cod recovery plan, Ispra, 13-17 June and 19-21 September 2005. ICES Advice 2009, Book 6 121

Saithe in IIIa and IV Year ICES Advice 2004 onwards: Single-Stock Exploitation Boundaries Predicted landings corresp. to advice Predicted landings correp. to single-stock exploitation boundaries Agreed TAC Official landings ICES landings 1987 Reduce F <198 173 154 149 1988 60% of F(86); TAC 156 165 113 107 1989 No increase in F; TAC 170 170 92 92 1990 No increase in F; TAC 120 120 85 88 1991 No increase in F; TAC 125 125 93 99 1992 No increase in F; TAC 102 110 92 92 1993 70% of F(91) ~ 93 000 t 93 93 99 105 1994 Reduce F by 30% 72 97 90 102 1995 No increase in F 107 107 97 113 1996 No increase in F 111 111 96 110 1997 No increase in F 113 115 86 103 1998 Reduce F by 20% 97 97 88 100 1999 Reduce F to F pa 104 110 108 107 2000 Reduce F by 30 % 75 85 85 87 2001 Reduce F by 20 % 87 87 88 90 2002 F < F pa <135 135 113 117 2003 F < F pa <176 165 105 102 2004 F < F pa <211 190 87 100 2005 F according to man. plan * <137 145 111 112 2006 F according to man. plan (< F pa ) * <123 123 111 117 2007 F according to man. plan (< F pa ) * <124 123 87 94 2008 F according to man. plan (< F pa ) * <137 136 115 112 2009 F according to man. plan (< F pa ) * <126 126 2010 F according to man. plan (< F pa ) * <107 Weights in 000 t. * Single-stock boundary and the exploitation of this stock should be conducted in the context of mixed fisheries. 122 ICES Advice 2009, Book 6

Saithe in VI Year ICES Advice 2004 onwards: Single-Stock Exploitation Boundaries* Predicted landings corresp. to advice Predicted catch corresp to single-stock exploitation boundaries Agreed TAC Official landings ICES landings 1987 F reduced towards F max 19 27.8 32.5 31.4 1988 80% of F(86); TAC 35 35 32.8 34.2 1989 F < 0.3; TAC 20 30 22.4 25.6 1990 80% of F(88); TAC 24 29 18.0 19.9 1991 Stop SSB decline; TAC 21 22 17.9 17.0 1992 Avoid further reduction in SSB <19 17 10.8 11.8 1993 F = 0.21 6.3 14 14.5 13.9 1994 Lowest possible F 14 13.0 2 12.8 1995 Significant reduction in effort - 16 10.6 2 11.8 1996 No increase in F 10.2 1 13 9.4 2 9.4 1997 Significant reduction in F 12 8.6 2 9.4 1998 60% Reduction in F 4.8 10.9 7.4 2 8.4 1999 60% reduction in F 4.8 7.5 6.8 7.3 2000 Reduce F by 30% 6.0 7 6.4 5.9 2001 Reduce F by 20% 9.0 9 8.7 8.4 2002 F < F pa <13 14 5.6 5.2 2003 F < F pa <17 17.1 5.0 5.3 2004 F < F pa <21 <21 20 1.6 4.4 2005 F according to man. plan (< F pa ) <14 < 14 15 8.7 5.7 2006 F according to man. plan (< F pa )* * <12 13 9.4 8.6 2007 F according to man. plan (< F pa ) * <12 13 6.7 6.8 2008 F according to man. plan (< F pa ) * <14 14 6.0 7.1 2009 F according to man. plan (< F pa ) * <13 13 2010 F according to man. plan (< F pa ) * <11 Weights in 000 t. 1 Status quo catch. 2 Incomplete data. * Single-stock boundary and the exploitation of this stock should be conducted in the context of mixed fisheries. ICES Advice 2009, Book 6 123

Landings Landings in 1000 t 400 350 300 250 200 150 100 50 0 1967 1972 1977 1982 1987 1992 1997 2002 2007 F(ages 3-6) Fishing Mortality 0.9 0.8 0.7 0.6 0.5 0.4 0.3 0.2 0.1 0.0 1967 1972 1977 1982 1987 1992 1997 2002 2007 F Flim Fpa Recruitment (age 3) Recruitment in millions 450 400 350 300 250 200 150 100 50 0 1967 1972 1977 1982 1987 1992 1997 2002 2007 Spawning Stock Biomass SSB in 1000 t 600 500 400 300 200 100 0 1967 1972 1977 1982 1987 1992 1997 2002 2007 SSB Blim Bpa Figure 6.4.12.1 Saithe in Subarea IV, Division IIIa (Skagerrak), and Subarea VI. Landings, fishing mortality, recruitment, and SSB. 124 ICES Advice 2009, Book 6

Stock - Recruitment 450 Recruitment (age 1) in millions 400 350 300 250 200 150 100 50 0 0 100 200 300 400 500 600 SSB-Rec. Blim Bpa SSB in 1000 t Yield (dashed line) 0.9 0.8 0.7 0.6 0.5 0.4 0.3 0.2 0.1 0 Yield and Spawning Stock Biomass per Recruit 12 10 8 6 4 2 0 0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 Fishing Mortality (ages 3-6) SSB (line) 600 500 Precautionary Approach Plot Period 1967-2008 SSB in 1000 t 400 300 200 100 0 0.0 0.2 0.4 0.6 0.8 1.0 Fishing Mortality (ages 3-6) F-SSB 2008 Flim Fpa Blim Bpa Figure 6.4.12.2 Saithe in Subareas IV and VI, and Division IIIa. Precautionary approach plot, yield-per-recruit analysis, and stock recruitment plot. ICES Advice 2009, Book 6 125

Figure 6.4.12.3 Saithe (in Subareas IV and VI, and Division IIIa. Results of the North Sea Commission fishers survey 2008. Saithe in Subarea IV (North Sea) Division IIIa West (Skagerrak) and Subarea VI (West of Scotland and Rockall) 400 350 SSB ('000 tonnes) 0.90 0.80 Fishing mortality: 3-6 500 450 Millions Recruitment. Age: Age: 3 0 300 0.70 400 250 200 150 100 0.60 0.50 0.40 0.30 0.20 350 300 250 200 150 100 50 0.10 50 0 1990 1995 2000 2005 0.00 1990 1995 2000 2005 0 1990 1995 2000 2005 Figure 6.4.12.4 Saithe in Subareas IV and VI, and Division IIIa. Historical performance of the assessments. Note: recruitment age was changed from 1 to 3 in 2004. 126 ICES Advice 2009, Book 6

Table 6.4.12.1 Saithe in Subarea IV, Division IIIa (Skaerrak), and Subarea VI. Landings in tonnes. Saithe IV and IIIa Country 1999 2000 2001 2002 2003 2004* 2005* 2006 2007* 2008* Belgium 200 122 24 107 45 22 28 16 18 7 Denmark 4494 3529 3575 5668 6954 7991 7498 7471 5458 8069 Faroe Islands 1101-289 872 495 558 184 62 15 108 France 24305 1 * 19200 20472 25441 18001 13628 10768 15739 13043 15302 Germany 10481 9273 9479 10999 8956 9589 12401 14390 12790 14141 Greenland - 601 2 * 1526 2 * 62 1616 403 - - - - Ireland - 1 - - - 1-0 - 81 Netherlands 7 11 20 6 1* 3 40 28 5 3 Norway 56150 43665 44397 60013 61735 62783 67365 61268 45395 62055 Poland 862 747 727 752 734* 0 1100 - - 1407 Russia - 67 - - - - 35 2 5 5 Sweden 1929 1468 1627 1863 1876 2249 2114 1695 1380 1639 UK (E/W/NI) 2874 1227 1186 2521 1215 457 1190 UK (Scotland) 5420 5484 5219 6596 5829 5924 7703 9129** 9628** 11701** Total reported 107823 85395 88541 114900 107467 103608 110575 109800 87377 114517 Unallocated -509 2281 1030 1291-5809 -3646 968 7312 6241-2263 W.G. Estimate 107314 87676 89571 116191 101658 99962 111543 117112 93618 112254 TAC 110000 85000 87000 135000 165000 190000 145000 123250 123250 135900 *Preliminary, 1 reportedbytacarea, IIa(EC), IIIa-d(EC) and IV, 2 Preliminary data reported in IVa **Scotland+E/W/NI combined Saithe VI Country 1999 2000 2001 2002 2003 2004* 2005* 2006 2007* Faroe Islands 2 - - - 2 34 21 76 32 France 3467 1 * 3310 5157 3062 3499 3053 3452 5782 3956 Germany 250 305 466 467 54 4 373 532 580 Ireland 320 410 399 91 170 95 168 243 322 Netherlands - - - - - - - - - Norway 126 58 31 12 28 16 20 28 377 Russia 3 25 1 1 6 6 25 7 2 Spain 23 3 15 4 6 2 3 - - UK (E/W/NI) 503 276 273 307 263 37 203 UK (Scotland) 2084 2463 2246 1567 1189 1563 4433 2748** 1419** Total reported 6778 6850 8588 5513 5215 4810 8699 9416 6688 Unallocated 564-960 -1770-327 35-296 -2960 848 98 W.G.Estimate 7342 5890 6818 5186 5250 4514 5739 8568 6786 TAC 7500 7000 9000 14000 17119 20000 15044 12787 12787 *Preliminary, 1 reported by TAC area, IIa(EC), IIIa-d(EC) and IV **Scotland+E/W/NI combined SAITHE IV, IIIa and VI 1999 2000 2001 2002 2003 2004 2005 2006 2007 WG estimate 114656 93566 96389 121377 106908 104476 117282 125680 100404 TAC 117500 92000 96000 149000 182119 210000 160044 136037 136037 ICES Advice 2009, Book 6 127

Table 6.4.12.2 Saithe in Subarea IV, Division IIIa (Skagerrak), and Subarea VI. Summary of stock assessment. Year Recruitment SSB Landings Mean F Age 3 Ages 3-6 thousands tonnes tonnes 1967 127456 150838 88326 0.322 1968 114114 211723 113751 0.292 1969 300688 263959 130588 0.262 1970 291835 312007 234962 0.408 1971 327931 429569 265381 0.329 1972 171372 474093 261877 0.395 1973 152852 534485 242499 0.416 1974 148740 554906 298351 0.556 1975 181239 472066 271584 0.482 1976 384110 351532 343967 0.760 1977 118014 263121 216395 0.615 1978 92451 268089 155141 0.477 1979 77643 241049 128360 0.396 1980 67133 235143 131908 0.443 1981 172784 241188 132278 0.306 1982 109900 210413 174351 0.469 1983 118183 214208 180044 0.548 1984 205166 176557 200834 0.678 1985 311635 160711 220869 0.716 1986 287798 151680 198596 0.822 1987 112969 153043 167514 0.651 1988 115054 148010 135172 0.630 1989 77604 114932 108877 0.687 1990 119906 102875 103800 0.611 1991 138452 100562 108048 0.583 1992 92781 102305 99742 0.628 1993 151493 108043 111491 0.517 1994 102360 116568 109622 0.518 1995 224246 134909 121810 0.425 1996 110295 154066 114997 0.423 1997 162820 193789 107327 0.296 1998 71182 192533 106123 0.353 1999 139349 201499 110716 0.368 2000 94158 187822 91322 0.316 2001 221180 209592 95042 0.284 2002 186590 202663 115395 0.256 2003 123594 232871 105569 0.235 2004 86544 275550 104237 0.203 2005 211248 279259 124532 0.270 2006 56975 276982 125680 0.293 2007 173990 264365 101202 0.264 2008 72416 260586 119305 0.303 2009 122000* 263377 Average 156471 237059 154228 0.448 *GM(1988-2006) 128 ICES Advice 2009, Book 6

Annex 6.4.12 Management plan In 2008 EU and Norway renewed the existing agreement on a long-term plan for the saithe stock in the Skagerrak, the North Sea and west of Scotland, which is consistent with a precautionary approach and designed to provide for sustainable fisheries and high yields. The plan shall consist of the following elements. 1. Every effort shall be made to maintain a minimum level of Spawning Stock Biomass (SSB) greater than 106,000 tonnes (B lim ). 2. Where the SSB is estimated to be above 200,000 tonnes the Parties agreed to restrict their fishing on the basis of a TAC consistent with a fishing mortality rate of no more than 0.30 for appropriate age groups. 3. Where the SSB is estimated to be below 200,000 tonnes but above 106,000 tonnes, the TAC shall not exceed a level which, on the basis of a scientific evaluation by ICES, will result in a fishing mortality rate equal to 0.30-0.20*(200,000-SSB)/94,000. 4. Where the SSB is estimated by the ICES to be below the minimum level of SSB of 106,000 tonnes the TAC shall be set at a level corresponding to a fishing mortality rate of no more than 0.1. 5. Where the rules in paragraphs 2 and 3 would lead to a TAC which deviates by more than 15 % from the TAC of the preceding year the Parties shall fix a TAC that is no more than 15 % greater or 15 % less than the TAC of the preceding year. 6. Notwithstanding paragraph 5 the Parties may where considered appropriate reduce the TAC by more than 15 % compared to the TAC of the preceding year. 7. A review of this arrangement shall take place no later than 31 December 2012. 8. This arrangement enters into force on 1 January 2009. ICES Advice 2009, Book 6 129

6.4.13 Nephrops in Division IIIa (Skagerrak Kattegat) There are two Functional Units in Division IIIa: Skagerrak (FU 3) and Kattegat (FU 4). The advice for 2009 is biennial and valid for 2009 and 2010 (see ICES, 2008). The 2008 assessment had lead to the conclusion for the two FUs in Division IIIa that, given the apparent stability of the stocks, the current levels of exploitation appeared to be sustainable. The most recent assessment data compiled in 2009 do not indicate any changes in the state of the stock. Source of information ICES 2009. Report of the Working Group on the Assessment of Demersal Stocks in the North Sea and Skagerrak, 6 12 May 2009 (ICES CM 2009/ACOM:10) ICES, 2008. Report of the ICES Advisory Committee 2008. ICES Advice, 2008. Book 6. Table 6.4.13.1 Nephrops in Division IIIa (Skagerrak Kattegat). Single-stock exploitation boundaries (advice), management and landings. Year ICES advice Recommended TAC Agreed TAC ICES landings 1 1987 4.0 1988 3.7 1989 3.9 1990 4.3 1991 4.2 1992 ~4.0 3.5 2.9 1993 ~4.3 3.5 3.2 1994 2.9 3.5 2.9 1995 2.9 4.8 3.4 1996 Status quo TAC 2.9 4.8 4.0 1997 Status quo TAC 2.9 4.8 4.2 1998 4.0 4.8 5.0 1999 4.0 4.8 4.9 2000 3.8 5.0 4.7 2001 3.8 4.5 4.1 2002 Catches to be maintained at the 2000 level 4.7 4.5 4.4 2003 Catches to be maintained at the 2000 level 4.7 4.5 3.8 2004 Catches to be maintained at the 2000 level 4.7 4.7 4.0 2005 Catches to be maintained at the 2000 level 4.7 5.2 4.0 2006 No increase in effort 5.2 3.7 2007 No increase in effort 5.2 4.5 2008 No increase in effort 5.2 4.9 2009 Current effort appears to be sustainable 5.2 2010 Current effort appears to be sustainable Weights in 000 t. 1) Does not include discards. 130 ICES Advice 2009, Book 6

6.4.14 Nephrops in Subarea IV (North Sea) Nephrops are limited to a muddy habitat. This means that the distribution of suitable sediment defines the species distribution and the stocks are therefore assessed as eight separate functional units (Figure 6.4.14.1): Section FU no. Name ICES area Statistical rectangles 6.4.14.1* 5 Botney Gut - Silver Pit IVb,c 36-37 F1-F4; 35F2-F3 6.4.14.2 6 Farn Deeps IVb 38-40 E8-E9; 37E9 6.4.14.3 7 Fladen Ground IVa 44-49 E9-F1; 45-46E8 6.4.14.4 8 Firth of Forth IVb 40-41E7; 41E6 6.4.14.5 9 Moray Firth IVa 44-45 E6-E7; 44E8 6.4.14.6* 10 Noup IVa 47E6 6.4.14.7* 32 Norwegian Deep lva 44-52 F2-F6; 43F5-F7 6.4.14.8* 33 Off Horn Reef lvb 39-41E4; 39-41E5 * The advice for these stocks was given in biannual advice in 2008, see ICES (2008a). Figure 6.4.14.1 Nephrops Functional Units in the North Sea and Skagerrak/Kattegat region (see Section 6.4.13). General features of Nephrops in IV. An overview of advice for different functional units is presented in Table 6.4.14.1. Management considerations The overriding management consideration for these stocks is that management should be at the Functional Unit (FU) rather than the ICES Subarea level. Management at the Functional Unit level should provide the controls to ensure that catch opportunities and effort are compatible and in line with the scale of the resources in each of the stocks defined by the Functional Units. Current management of Nephrops in Subarea IV (both in terms of TACs and effort) does not provide adequate safeguards to ensure that local effort is sufficiently limited to avoid depletion of resources in Functional Units. In the current situation vessels are free to move between grounds, allowing effort to develop on some grounds in a largely uncontrolled way and this has historically resulted in inappropriate harvest rates from some parts. ICES Advice 2009, Book 6 131

This is a particular problem in the Farn Deeps where increased vessel activity from other parts of the UK occurred resulting in low stock levels. There are no precautionary reference points defined for Nephrops. This year ICES has provided advice on a range of catch options including a long term exploitation rate for Nephrops based on a number of considerations: For many stocks ICES considers that exploitation rates between F 0.1 and F max are an appropriate range of exploitation rates. For Nephrops both F 0.1 and F max are often well defined. There are a substantial number of studies on exploitation of fin fish indicating that F 0.1 is consistent with maximising sustainable long term yield, though this has not been studied directly for Nephrops and further work is required to ascertain whether fishing at F 0.1 is consistent with the management objective of maximising yield of Nephrops. F max is often considered too high an exploitation rate, leading to increasing risk to SSB without any substantial increases in yield. In addition for stocks with high discard rates a reduction of harvest rates often reduces the rates of exploitation of smaller individuals allowing larger numbers for the fishery in subsequent years. A limited number of management simulations have been carried out (Dobby, 2007) on two of the FU in the NS showing that harvest ratios of close to F 0.1 are appropriate for sustainable high long term yield with risks that ICES would consider precautionary. Ideally these simulations should be extended to other Nephrops FUs. The higher exploitation rates of the order of F max have not been explicitly tested but its unlikely that they will provided the same stability of yield and will have higher risks. These simulations did not explicitly deal with surveys that had different selection patterns from the fishery, there may be increases in risk associated with this, reinforcing the greater applicability of the lower exploitation rates. For a number of FUs in the North Sea (and Celtic Seas) the recent catches have been substantially higher than the rates implied by F 0.1. In the case of Firth of Forth (FU8) these catches have been even higher than the rate implied by F max but this coincided with an apparent increase in the stock in the last few years. In light of the above considerations, ICES advises that F should be in the range of F 0.1 to F max to maximize long term average yield without unduly risking SSB. ICES advice for individual functional units takes account of the current estimate of F and trend in SSB as follows: F relative to F 0.1 and F max SSB Stable or Increasing SSB Decreasing F > F max Reduce F to F max Reduce F to F 0.1 F max > F > F 0.1 Maintain current F Reduce F to F 0.1 F < F 0.1 Increase F to F 0.1 Maintain current F Where the new advice suggests a large change in landings, a constraint on the year to year change in catches as is typical of management plans and the Communication on Fishing Opportunities for 2010 [COM (2009) 224] might be considered. Some combinations of F and trend in SSB are included for completeness, even though not all of these combinations have been applied to North Sea Nephrops. In general, catches of cod in the Nephrops fisheries have been relatively low, particularly in recent years in inshore grounds of Subarea IV, but can vary amongst Functional Units. However, it is important that emerging year classes of cod should not be subject to high discard mortality. The capture of juvenile fish or other species such as haddock is also a problem in some of the Functional Units and discarding of these is a problem in some years. This problem is being addressed with the use of more selective gear and efforts are already being made in Scotland through the Conservation Credits scheme, requiring vessels targeting Nephrops to use gear with larger square meshed panels (110 mm). Subject to evaluation of the effectiveness of these measures, further action may be required to reduce discards. The advice is presented separately for each Functional Unit. In addition, there are increasing and significant landings from some isolated patches outside the Functional Units, most notably the Devil s Hole area. Table 6.4.14.1 below shows that in 2008 overall landings in Subarea IV were around 22 100 tonnes, similar to landings in 2005. Landings from other rectangles have risen steadily and amounted to over 1 600 tonnes in 2008. To provide some guidance on appropriate future landings for these areas, the use of average landings of no more than 1500 tonnes (2006 2008) could be considered (Table 6.4.14.1). 132 ICES Advice 2009, Book 6

Impacts of fisheries on the ecosystem Trawling for Nephrops results in bycatch and discards of other species, including cod, haddock, and whiting. 80 mm is the predominant mesh size used in Nephrops fisheries and the resulting proportion of fish discarded can be high. Initiatives are in place to reduce discarding (see Regulations and their effects below). The high mud content and soft nature of Nephrops grounds means that trawling readily marks the seabed, trawl marks remaining visible for some time. Burrowing fauna can be seen re-emerging from freshly trawled grounds, implying that there is some resilience to trawling. Cod has been identified as a major predator of Nephrops in some areas. The generally low level of the cod in the North Sea is likely to have resulted in reduced predation. Multi-species models applied in the past to the exploitation of Irish Sea stocks indicated that management strategies which lead to an increase in the cod stock are associated with a reduction in Nephrops abundance. Therefore it may be expected that Nephrops stocks in the North Sea may decrease when cod recovers. Factors affecting the fisheries and the stock Regulations and their effects The implementation of the buyers and sellers regulations in the UK in 2006 considerably tightened up the levels of reporting for Nephrops, and the landings figures since then are considered to be more reliable. Recent increases in landings and lpue may result from the increase in reporting levels and do not necessarily reflect changes to the stock. A ban on the use of multi-trawl gears (3 or more trawls) for all Scottish boats was introduced from April 2008, limiting the expansion of effective effort. Days-at-sea regulations and recently introduced effort allocation schemes (kw*day) have reduced opportunities for directed whitefish fishing. STECF 2008 stated that the overall effort (kw*days) by demersal trawls, seines and beam trawls shows a substantial reduction since 2002. However, there have also been substantial changes in the usage of the different mesh size categories by the demersal trawls. In particular there has been a sharp reduction in usage of gears with a mesh size of between 100mm and 119mm (targeting whitefish), and a subsequent general increase in effort by vessels using smaller mesh sizes (targeting Nephrops for instance) or larger (targeting whitefish). The development of a Conservation Credits scheme in Scotland (the major contributor to landings from the Fladen Ground) requires all trawlers to implement more selective gears, including the use of 110 mm square mesh panels in 80 mm gear. This measure aims to reduce catches (and discards) of small fish, including whiting, haddock, and juvenile cod. Scientific basis Data and methods Assessments of the Nephrops Functional Units of Subarea IV utilized a number of approaches, including Underwater UWTV surveys (UWTV) surveys, length composition information, and basic fishery data such as landings and effort. Owing to uncertainties in the accuracy of historic landings and to inaccurate effort figures in some fisheries, increasing attention is paid to survey information and size composition data as an indicator of stock status. For those stocks without UWTV surveys, assessment is made on the basis of analysis of length compositions, trends in mean length for recruit classes and commercial CPUE. Biennial advice for these stocks was given in 2008 so no new advice is given this year. There have been important developments in the methodology to assess the status of Nephrops stocks. The use of UWTV surveys has enabled the development of fishery-independent indicators of abundance. STECF (2005) had suggested that a combination of an absolute abundance estimate from an UWTV survey and a harvest rate based on F 0.1 from a combined sex length cohort analysis (LCA) and the mean weight and selection pattern from the commercial fishery could be used to calculate appropriate landings. The approach has been further developed and evaluated by ICES workshops in 2007 and 2009 (ICES, 2007, ICES 2009b). The 2009 workshop addressed concerns raised regarding factors which could potentially bias the UWTV survey results. Major sources of bias were quantified for each survey and an overall bias correction factor derived which, when applied to the estimates of abundance from the UWTV survey allows them to be treated as absolute abundance levels. ICES Advice 2009, Book 6 133

In particular the workshop concluded that the UWTV surveys detect the burrows of Nephrops considerably smaller than the sizes of those taken by the fishery. Therefore the abundance estimates used to calculate the Harvest Ratios presented in the 2009 advice include a component of the stock that is too small to be exploited by the fishery. This has resulted in calculated Harvest Ratios appearing to have decreased in the current advice compared to previous estimates of Harvest Ratios. In essence, this is a scaling issue, not a change in exploitation rate. The previous proportion corresponding to fishing at F 0.1 were in the range of 15-20% whereas the revised values from the benchmark in 2009 are in the range of 8-10%. Information from the fishing industry Trends according to the North Sea fishers survey indicate disparate patterns of stock development. Long term increases in stock have been observed over most areas, but since 2007 the majority of areas show a small decline, except for Farn Deep (FU6) that shows a sharp decline (Figure 6.4.14.3). Uncertainties in assessment and forecast For moderate exploitation rates the UWTV assessment provides an adequate basis for predicting catches. ICES groups WKNephTV (ICES 2007), WKNephBid (ICES 2008b), SGNepS (ICES 2009a) have progressively worked to reduce uncertainty and increase precision in the interpretation of survey data. There is a gap of at least 12 months (more commonly 18 months) between the survey and the start of the TAC year. It is assumed that the stock is stable during this period (i.e. recruitment and growth balance mortality). The effect of this assumption on realised harvest rates has not been investigated. The UWTV survey does not cover the complete spatial distribution of the stock, covering 4 out of 8 Functional Units and not the area outside the Functional Units. The area covered by the UWTV survey accounts for 79% of the landings in 2008. Landings from outside the FUs account for 8% of total landings. Vessel Monitoring System (VMS) data for vessels > 15 meters are being successfully used to match survey and fishery areas. The calculations of harvest ratio and F 0.1 are all based on yield-per-recruit analyses from length cohort analyses. These analyses utilise average length frequency data taken over a 3 year period and therefore apply to stocks in equilibrium. However, it is unlikely that the Nephrops stocks to which the approach has been applied are actually in equilibrium due to variable recruitment. F 0.1 estimates may vary in time due to changes in selection pattern. Prior to the implementation of Buyers and Sellers legislation in 2006 reporting rates are considered to have been low and hence the estimated Harvest Ratios prior to 2006 are also likely to have been underestimated. The reliability of fishery statistics is improving but the transition period is accompanied in some cases by large changes in landings which produce significant changes in the lpue and cpue series that cannot be completely attributed to changes in stock. Until a sufficient time series of reliable data has built up, use of fishery catch and effort data in the assessment process should be avoided. Comparison with previous assessment and advice For those stocks without UWTV surveys, advice given in 2008 was biennial and therefore no new advice is given this year. The advice basis for stocks with UWTV surveys has fundamentally changed since 2008. In 2008, ICES considered the UWTV indices to show relative trends and not absolute abundance. Consequently the advice was given in terms of maintaining landings at or below recent levels.. Sources of information ICES 2007. Workshop on the Use of UWTV Surveys for Determining Abundance in Nephrops Stocks throughout European Waters. WKNEPHTV. ICES CM 2007/ACFM:14. ICES, 2008a. Report of the ICES Advisory Committee 2008. ICES Advice, 2008. Book 6, 326pp. ICES 2008b. Workshop and training course on Nephrops burrow identification (WKNEPHBID). ICES CM 2008/LRC:03 ICES 2009a. Study Group on Nephrops Surveys (SGNEPS) ICES CM 2009/LRC:15 ICES 2009b. ICES. 2009. Report of the Benchmark Workshop on Nephrops (WKNEPH), 2 6 March 2009, Aberdeen, UK. ICES CM 2009/ACOM:33. (awaiting publication). ICES 2009.c Report of the Working Group on the Assessment of Demersal Stocks in the North Sea and Skagerrak, 6 12 May 2009 (ICES CM 2009/ACOM:10). 134 ICES Advice 2009, Book 6

Dobby, H., Bailey, N., and Campbell, N. 2007. The use of underwater TV surveys in the provision of advice for Nephrops stocks around Scotland. ICES CM 2007/O:23. Dobby, H. 2007. Deriving appropriate harvest rates for the Nephrops stocks around Scotland. Working Document for ICES, 2007 WKNEPHTV. Laurenson, C. H. 2008. North Sea Stock Survey 2008. NAFC Marine Centre, Shetland, UK. STECF. 2005. Commission Staff Working Paper. 21 st Report of the Scientific, Technical and Economic Committee for Fisheries (Second Plenary Meeting). Brussels, 7 11 November 2005. STECF PLEN-08-03 EUR 23624 EN, ISBN 978-79-10940-9, ISSN 1018-5593, DOI 10.2788/3484, 2008 Table 6.4.14.1 Nephrops in Subarea IV. Summary of the advice by Functional Unit plus Other rectangles. Year Moray Firth (FU9) Noup (FU10) Fladen Ground (FU7) Norwegian Deeps (FU32) Farn Deeps (FU6) Firth of Forth (FU8) Botney Gut- Silver Pit (FU5) Off Horn s Reef (FU33) Other rectangles 2) Total advice 5) Agreed TAC 1) ICES landings Mgt Area MA F MA G MA S MA I MA H 1992 ~2.4 ~2.7 ~4.6 0.87 10.6 12.0 9.5 1993 2.4 2.7 4.17 0.87 10.2 12.0 12.7 1994 2.4 5.0 4.17 0.87 12.5 13.0 14.2 1995 2.4 5.0 4.17 0.87 12.5 15.2 14.7 1996 2.4 5.0 4.17 0.87 12.5 15.2 13.7 1997 2.4 5.0 4.17 0.87 12.5 15.2 15.2 1998 2.4 7.0 4.17 1.0 14.6 15.2 13.7 1999 2.4 7.0 4.17 1.0 14.6 15.2 16.5 2000 1.85 9.0 4.17 1.6 16.7 17.2 15.1 2001 1.85 9.0 4.17 1.6 16.7 15.48 15.9 2002 2.0 9.0 1.2 4.17 2.1 18.5 16.623 15.7 2003 2.0 9.0 1.2 4.17 2.1 18.5 16.623 15.6 2004 2.0 12.8 1.5 4.17 2.38 22.9 21.350 18.6 2005 2.0 <12.8 1.5 4.17 2.38 22.9 21.350 21.9 2006 - - NA - 2.38 NA 28.147 24.4 2007 2.4 0.2 <10.9 NA 3.5 1.5 NA NA 24.6 6) NA 26.144 24.6 2008 2.4 0.2 <10.9 NA 3.5 1.5 NA NA 9.5 6) NA 26.144 22.1 2009 < 1.8 < 0.24 < 11.3 -- 3 < 3.0 < 2.5 -- 3 -- 3 < 1.4 NA 24.837 2010 <1.37 < 0.24 4 <16.4 -- 4 <1.2 <1.57 -- 4 -- 4 < 1.5 NA Weights in 000 t. 1) EU zone of Division IIa and Subarea IV. 2) Prior to advice for 2009, landings for other rectangles were included in 'Management Areas (MA). 3) No increase in effort. 4) Biennial advice given in 2008. 5) It is not advised to manage these stocks as a single unit. 6) refers to advice for FU 5, 32 and 33 ICES Advice 2009, Book 6 135

30000 25000 20000 15000 10000 5000 0 1991 1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008* Tonnes Other IV FU 33 FU 32 FU 10 FU 9 FU 8 FU 7 FU 6 FU 5 Year Figure 6.4.14.2 Nephrops in Subarea IV. Total landings divided into Functional Units and Other rectangles (tonnes). 136 ICES Advice 2009, Book 6

Figure 6.4.14.3 Nephrops in Subarea IV. Results of the North Sea Commission fishers survey 2008. ICES Advice 2009, Book 6 137

Table 6.4.14.2 Nephrops in Subarea IV. Officially reported landings (tonnes) by Functional Unit plus Other rectangles. Year FU 5 FU 6 FU 7 FU 8 FU 9 FU 10 FU 32 FU 33 Other IV Total 1981 1073 373 1006 1416 36 76 3980 1982 2524 422 1195 1120 19 157 5437 1983 2078 693 1724 940 15 101 5551 1984 1479 646 2134 1170 111 88 5628 1985 2027 1148 1969 2081 22 139 7386 1986 2015 1543 2263 2143 68 204 8236 1987 2191 1696 1674 1991 44 195 7791 1988 2495 1573 2528 1959 76 364 8995 1989 3098 2299 1886 2576 84 233 10176 1990 2498 2537 1930 2038 217 222 9442 1991 862 2063 4220 1404 1519 196 560 10824 1992 612 1473 3338 1757 1591 188 401 9360 1993 721 3030 3521 2369 1808 376 339 160 434 12759 1994 503 3683 4566 1850 1538 495 755 137 703 14230 1995 869 2569 6442 1763 1297 280 489 164 844 14717 1996 679 2482 5220 1688 1451 344 952 77 808 13701 1997 1149 2189 6171 2194 1446 316 760 276 662 15163 1998 1111 2177 5138 2145 1032 254 836 350 694 13736 1999 1244 2391 6505 2205 1008 279 1119 724 988 16463 2000 1121 2178 5580 1785 1541 275 1084 597 900 15060 2001 1443 2574 5545 1528 1403 177 1190 791 1268 15919 2002 1231 1953 7234 1340 1118 401 1170 861 1383 16691 2003 1144 2245 6305 1126 1079 337 1089 929 1390 15644 2004 1070 2152 8733 1658 1335 228 922 1268 1224 18590 2005 1058 3094 10685 1990 1605 165 1089 1050 1120 21855 2006 986 4858 10789 2458 1803 133 1028 1288 1249 24591 2007 1311 2966 11910 2652 1842 155 755 1467 1637 24695 2008* 695 1213 12240 2450 1514 173 675 1444 1673 22077 * Preliminary 138 ICES Advice 2009, Book 6

6.4.14.1 Nephrops in Botney Gut Silver Pit (FU 5) The advice for 2009 is biannual and valid for 2009 and 2010 (see ICES, 2008). Table 6.4.14.1.1 Nephrops in Botney Gut Silver Pit (FU 5). Single-stock exploitation boundaries (advice), management, and landings. Year ICES advice Recommended landings ICES Landings 1 1991 0.9 1992 0.87 0.6 1993 0.87 0.7 1994 0.87 0.5 1995 0.87 0.9 1996 0.87 0.7 1997 0.87 1.1 1998 1.0 1.1 1999 1.0 1.2 2000 1.6 1.1 2001 1.6 1.4 2002 2.1 1.2 2003 2.1 1.1 2004 2.38 1.1 2005 2.38 1.1 2006 2.38 2) 1.0 2007 No increase in effort - 1.3 2008 No new advice, same as for 2007-0.7 2009 No increase in effort - 2010 No new advice, same as for 2009 - Weights in 000 t. 1) Does not include discards. 2) Includes Off Horns Reef FU 33. ICES Advice 2009, Book 6 139

6.4.14.2 Nephrops in Farn Deeps (FU 6) State of the stock The UWTV survey, fishery data and length frequency data all point to the stock at the start of the 2008 fishing season continuing to be at a low level. Recruitment signals for Nephrops in 2008 appear to indicate low recruitment. Reference points F Harvest Technical basis reference point ratio F 0.1 8.2% WKNEPH 2009 F max 13.3% WKNEPH 2009 (unchanged since 2009) Single-stock exploitation boundaries ICES advises on the basis of exploitation boundaries in relation to high long term yield and low risk of depletion of production potential that the Harvest Rate for Nephrops fisheries should not exceed F 2008. This corresponds to landings of no more than 1 210 t for the Farn Deeps stock. Basis: Bias corrected survey index (2008) = 965 Landings Rationale Harvest ratio 2010 (tonnes) 2% 318 4% 637 6% 955 F 2008 7.6% 1210 8% 1274 F 0.1 8.2% 1305 10% 1592 12% 1910 F max 13% 2117 14% 2229 16% 2547 18% 2866 20% 3184 Management considerations To protect the stock in this Functional Unit, management is required to be implemented at the Functional Unit level. Increases in abundance in other FUs (i.e. Firth of Forth and the Fladen grounds) are likely to translate to increases in TAC, increasing the risk of higher effort being deployed in this FU. The high cost of fuel combined with the relative coastal proximity of this ground may result in it attracting additional fishing effort which would be inadvisable given the current low level of the stock. Fishing effort in 2008 declined considerably due to fewer vessels visiting from Scotland and Northern Ireland. This brought the Harvest Rate in 2008 down to below the level considered to be equivalent to fishing at F 0.1. Without suitable controls on the movement of effort between Functional Units there is nothing to prevent the effort in 2010 returning to levels observed prior to 2008 all of which have been above the F 0.1 level and some of which have been considerably above the level of F max. Changes in fishing technology and fishing patterns Increases in the numbers of vessels using twin-rig gears observed in this area are likely to have increased the effective fishing power per kw hour. 140 ICES Advice 2009, Book 6

Poor catch rates during the 2007 2008 and 2008-2009 seasons resulted in several Scottish and Northern Irish vessels leaving the fishery early. Scientific basis Data and methods The UWTV survey has been conducted since 2002. Potential bias in survey design has been detected and accounted for in the assessment this year (see Data and methods section at the start of section 6.4.14). Length composition data from catch and discard sampling programmes have been used from 2002 to estimate the length composition of landings. Data prior to 2002 were raised using landings sampling due to insufficient discard sampling in this period. Information from the fishing industry The North Sea Stock Survey by the fishing industry showed a long term increase in abundance since 2001 followed by a marked decrease in abundance in 2008. This is consistent with the assessment. Fishing industry opinions appear divided regarding incoming recruitment with some respondents considering it to be good and some poor. Uncertainties in assessment and forecast General comments are found at the start of section 6.4.14 Direct landings sampling is likely to have missed portions of the landings landed as tails (as opposed to whole), leading to a significant overestimate of discarding above MLS. Comparison with previous assessment and advice The perception of the state of the stock has not changed since the assessment in 2008. The indicators show that the stock has been substantially reduced from a relatively high abundance in 2006. The advice in 2008 was based on recent landings as the UWTV surveys were considered inappropriate to use as absolute indices of abundance. Following the outcome of the benchmark in 2009, the major concerns of the UWTV survey have been addressed and the survey is now considered a reliable estimate of absolute abundance. The landings forecast for has changed considerably; in 2008 (for landings in 2009) it was less than 3000 t whereas the current advice for 2010 is for less than 1210 t based on F 2008. ICES Advice 2009, Book 6 141

Table 6.4.14.2.1 Nephrops Farn Deeps (FU 6). Single-stock exploitation boundaries (advice), management, and landings. Year ICES advice Recommended landings Farn Deeps (FU6) Recommended landings FU6+FU8 ICES Landings FU6 1) 1987 2.2 1988 2.5 1989 3.1 1990 2.5 1991 2.1 1992 ~4.6 1.5 1993 4.17 3.0 1994 4.17 3.7 1995 4.17 2.6 1996 4.17 2.5 1997 4.17 2.2 1998 4.17 2.2 1999 4.17 2.4 2000 4.17 2.2 2001 4.17 2.6 2002 4.17 2.0 2003 4.17 2.2 2004 4.17 2.2 2005 4.17 3.1 2006 No increase in effort - 4.9 2007 No increase in effort, harvest rate <15% 3.5 5.0 3.0 2008 No new advice, same as for 2007 3.5 5.0 1.2 2009 No increase in effort and landings (2007) < 3.0 NA 2) 2010 Harvest Rate no greater than that equivalent to fishing at F 2008 Weights in 000 t. 1) Does not include discards. 2) Advice given at FU level only. <1.2 NA 2) 142 ICES Advice 2009, Book 6

Figure 6.4.14.2.1 Nephrops Farn Deeps (FU 6): Long-term trends in landings, effort, lpues, and mean sizes of Nephrops. Abundance (millions) 0 500 1500 2500 1998 2000 2002 2004 2006 2008 Year Figure 6.4.14.2.2 Nephrops Farn Deeps (FU 6). Time-series of the bias adjusted UWTV survey index estimates, with 95% confidence intervals. ICES Advice 2009, Book 6 143

Figure 6.4.14.2.3 Nephrops Farn Deeps (FU 6). Length composition of catch (dotted) and landed (solid) of males (right) and females left from 1996 (bottom) to 2007 (top). Mean sizes of catch and landings (using same line types ) is shown in relation to Minimum Landing Size (MLS). 144 ICES Advice 2009, Book 6

Table 6.4.14.2.2 Nephrops Farn Deeps (FU 6). Official landings (tonnes). Year UK England UK Scotland Sub total Other countries** Total 1981 1006 67 1073 0 1073 1982 2443 81 2524 0 2524 1983 2073 5 2078 0 2078 1984 1471 8 1479 0 1479 1985 2009 18 2027 0 2027 1986 1987 28 2015 0 2015 1987 2158 33 2191 0 2191 1988 2390 105 2495 0 2495 1989 2930 168 3098 0 3098 1990 2306 192 2498 0 2498 1991 1884 179 2063 0 2063 1992 1403 60 1463 10 1473 1993 2941 89 3030 0 3030 1994 3530 153 3683 0 3683 1995 2478 90 2568 1 2569 1996 2386 96 2482 1 2482 1997 2109 80 2189 0 2189 1998 2029 147 2176 1 2177 1999 2197 194 2391 0 2391 2000 1947 231 2178 0 2178 2001 2319 255 2574 0 2574 2002 1739 215 1953 0 1953 2003 2031 214 2245 0 2245 2004 1952 201 2152 0 2152 2005 2936 158 3093 0 3094 2006 4385 434 4819 39 4858 2007 2525 437 2962 4 2966 2008* 969 244 1213 0 1213 * provisional na = not available ** Other countries includes Ne, Be and Dk Table 6.4.14.2.3 Nephrops Farn Deeps (FU 6). Survey indices with and without bias adjustment Year Bias. adjusted Unadjusted Abundance Abundance (millions) ± 95% CI (millions) ± 95% CI 1997 1500 125 1800 150 1998 1090 89 1308 107 1999 NA NA NA NA 2000 NA NA NA NA 2001 1685 67 2022 80 2002 1048 112 1258 134 2003 1085 90 1302 108 2004 1377 101 1652 121 2005 1657 148 1988 177 2006 1244 114 1492 137 2007 958 114 1149 137 2008 965 112 1158 134 ICES Advice 2009, Book 6 145

6.4.14.3 Nephrops Fladen Ground (FU 7) State of the stock UWTV observations indicate that the stock is fluctuating without obvious trend with estimates for the last 2 years increasing to the highest abundance in the series. Considering the UWTV result alongside the indications of stable or slightly increasing mean sizes in the length compositions of catches (of individuals >35mm carapace length) suggests that the stock is being exploited sustainably. The decline in mean length of smaller individuals in the catch may be indicative of recent good recruitment. Reference points F Harvest Technical basis reference point ratio F 0.1 9.3% WKNEPH 2009 F max 15.8% WKNEPH 2009 (unchanged since 2009) Single-stock exploitation boundaries ICES advises on the basis of exploitation boundaries in relation to high long term yield and low risk of depletion of production potential that the Harvest Rate for Nephrops fisheries should not exceed F 0.1. This corresponds to landings of no more than 16 419t for the Fladen Ground Basis: Bias corrected survey index (2008) = 7302 Rationale Harvest rate Landings 2010 (tonnes) 5.0% 8827 F 2008 8.0% 14124 F 0.1 9.3% 16419 10.0% 17655 15.0% 26482 F max 15.8% 27895 20.0% 35310 Management considerations To protect the stock in this Functional Unit, management is required to be implemented at the Functional Unit level. Nephrops fisheries in this area have a bycatch of cod. In 2005, high abundance of 0 group cod was recorded in Scottish surveys near to this ground. This year class of cod has subsequently contributed to slightly improved cod stock biomass and efforts are being made to avoid the capture of cod so that the stock can build further. In 2008 over 90% of the Scottish industry was operating under a voluntary Conservation Credits scheme and has implemented real time closures with a view to reducing unwanted bycatch of cod. Factors affecting the fisheries and the stock In the Fladen area the Nephrops stock is restricted to a generally continuous area of muddy sediments extending from 57 30 N to 60 N, and from 1 W to 1 30 E, with other smaller patches to the north. The Fladen Ground is the largest known Nephrops ground where fishing activity can shift spatially so that effort can vary on parts of the ground. Nearly three quarters of the landings are made by single-rig vessels and one-quarter by twin-rig vessels. 80 mm mesh is the commonest mesh size. Nearly 40% of the Nephrops landings at Fladen are reported as bycatch, in fisheries which may be described as mixed. The effects of regulations The minimum landing size for Nephrops on the Fladen Ground is 25 mm carapace length. Discarding takes place at sea, and rates averaged over the period 2005 to 2007 for this stock were 18% by number, or 11% by weight. 146 ICES Advice 2009, Book 6

Changes in fishing technology and fishing patterns In the early years of the fishery, effort was primarily directed to a region that could be reached within 12 hours steaming from ports along the NE coast of Scotland. In recent years, logbook information and GPS loggers show that vessels are fishing more widely over the ground, including to the far eastern and northern edges of the extensive mud area. High fuel prices may limit steaming to some of these areas in 2008. Scientific basis Data and methods The UWTV survey has been conducted since 1992. Potential bias in survey design has been detected and accounted for in the assessment this year (see Data and methods section at the start of section 6.4.14.) Information from the fishing industry The NSCFP stock survey shows an increase in Nephrops between 2001 and 2002, a slight decrease to 2003, and a marked increase up to 2007. Stock levels are considered to be similar or slightly less in 2008 (Figure 6.4.14.3). This information is broadly consistent with trends in the UWTV survey results. Uncertainties in assessment and forecast General comments are found at the start of section 6.4.14 The UWTV survey is conducted over the main part of the ground, representing an area of around 28 200 km 2 of suitable mud substrate (the largest ground in Europe). The Fladen Ground Functional Unit contains several patches of mud to the north of the ground which are fished, bringing the overall area of substrate to 30 633 km 2. This area is not surveyed but would add to the abundance estimate. The absolute abundance estimate for this ground is therefore likely to be underestimated by the current methodology. Comparison with previous assessment and advice The perception of stock in 2008 is similar to that in 2007 from the assessment in 2008. The advice in 2008 was based on recent landings as the UWTV surveys were considered inappropriate to use as absolute indices of abundance. Following the outcome of the benchmark in 2009, the major concerns of the UWTV survey have been addressed and the survey is now considered a reliable estimate of absolute abundance. The landings forecast for 2010 (equivalent to fishing at F 0.1 ) is 16,419 tonnes. This is an increase of almost 4,000 tonnes on the reported landings in 2008. ICES Advice 2009, Book 6 147

Table 6.4.14.3.1 Nephrops, Fladen (FU 7). Single-stock exploitation boundaries (advice), management, and landings. Year ICES advice Recommended Landings Fladen grounds (FU7) ICES Landings FU7 1) 1989 2.3 1990 2.5 1991 4.2 1992 ~2.7 3.4 1993 2.7 3.5 1994 5.0 4.6 1995 5.0 6.4 1996 5.0 5.2 1997 5.0 6.2 1998 7.0 5.1 1999 7.0 6.5 2000 9.0 5.6 2001 9.0 5.5 2002 9.0 7.2 2003 9.0 6.3 2004 12.8 8.7 2005 <12.8 10.7 2006 No increase of effort - 10.8 2007 No increase in effort and harvest rate below 7.5% <10.9 11.9 2008 No new advice, same as for 2007 <10.9 12.24 2009 No increase in effort and recent average landings <11.3 2010 Harvest Rate no greater than that equivalent to fishing at F 0.1 Weights in 000 t. 1) Does not include discards. <16.4 148 ICES Advice 2009, Book 6

Landings - International Denmark - All gears 14000 UK Scotland - All gears 12000 UK Scotland - Nephrops traw lers 10000 International 8000 6000 4000 2000 0 1960 1970 1980 1990 2000 2010 Figure 6.4.14.3.1 Nephrops, Fladen (FU 7). Long-term trends in landings, effort, lpues, and mean sizes of Nephrops. 9000 8000 7000 6000 5000 4000 3000 2000 1000 0 1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 Landings (tonnes) Effort ('000 hours trawling) 2007 2008 Effort - Scottish and Danish Nephrops trawlers 120 100 Scottish Danish 3500 3000 80 2500 2000 60 1500 40 1000 20 500 0 0 1960 1970 1980 1990 2000 2010 Effort (days) LPUE - Scottish and Danish Nephrops trawlers Mean sizes - Scottish Nephrops trawlers LPUE (kg/hour trawling) 180 600 160 Scottish Danish 140 500 120 400 100 80 300 60 200 40 20 100 0 0 1960 1970 1980 1990 2000 2010 LPUE (kg/day) Mean size (mm carapace length) 44 40 Catch Mal < 35 mm CL 36 Catch Fem < 35 32 Landings Mal < 35 Landings Fem < 35 28 Landings Mal > 35 Landings Fem > 35 24 1960 1970 1980 1990 2000 2010 Abundance (millions) Year Figure 6.4.14.3.2 Nephrops, Fladen (FU 7). Time-series of the bias adjusted UWTV survey index estimates, with 95% confidence intervals. ICES Advice 2009, Book 6 149

Table 6.4.14.3.2 Nephrops, Fladen (FU 7). Total landings (tonnes). Year All Nephrops gears combined Single rig Multirig Landings Effort LPUE Landings Effort LPUE Landings Effort LPUE 1981 304 8.6 35.3 304 8.6 35.3 na na na 1982 382 12.2 31.3 382 12.2 31.3 na na na 1983 548 15.4 35.6 548 15.4 35.6 na na na 1984 549 11.4 48.2 549 11.4 48.2 na na na 1985 1016 26.6 38.2 1016 26.6 38.2 na na na 1986 1398 37.8 37.0 1398 37.8 37.0 na na na 1987 1024 41.6 24.6 1024 41.6 24.6 na na na 1988 1306 41.7 31.3 1306 41.7 31.3 na na na 1989 1719 47.2 36.4 1719 47.2 36.4 na na na 1990 1703 43.4 39.2 1703 43.4 39.2 na na na 1991 3024 78.5 38.5 410 11.4 36.0 2614 67.1 39.0 1992 1794 38.8 46.2 340 9.4 36.2 1454 29.4 49.5 1993 2033 49.9 40.7 388 9.6 40.4 1645 40.3 40.8 1994 1817 48.8 37.2 301 8.4 35.8 1516 40.4 37.5 1995 3569 75.3 47.4 2457 52.3 47.0 1022 23.0 44.4 1996 2338 57.2 40.9 2089 51.4 40.6 249 5.8 42.9 1997 2713 76.5 35.5 2013 54.7 36.8 700 21.8 32.1 1998 2291 60.0 38.2 1594 39.6 40.3 697 20.5 34.0 1999 2860 76.8 37.2 1980 50.3 39.4 880 26.5 33.2 2000 2915 92.1 31.7 2002 62.9 31.8 913 29.2 31.3 2001 3539 108.2 32.7 2162 65.8 32.9 1377 42.4 32.5 2002 4513 109.6 41.2 2833 58.9 48.1 1680 50.7 33.1 2003 4175 53.7 77.7 3388 42.8 79.2 787 10.9 72.2 2004 7274 56.1 129.7 6177 47.5 130.2 1097 8.6 127.6 2005 8849 61.3 144.4 6834 43.4 157.5 2015 17.9 112.7 2006 9396 65.7 143.0 7149 50.2 142.4 2320 15.5 149.7 2007 11055 69.6 158.8 8232 52.2 157.7 2822 17.4 162.2 2008 11432 80.3 142.4 8247 58.8 140.3 3185 21.5 148.1 150 ICES Advice 2009, Book 6

Table 6.4.14.3.3 Nephrops, Fladen (FU 7). Survey indices with and without bias adjustment. Values after 2002 have been adjusted for revised camera parameters Year Mean density Abundance 95% confidence interval Adjusted for bias 95% confidence interval burrows/m² millions millions millions millions 1992 0.17 4942 508 3661 376 1993 0.21 6007 768 4450 569 1994 0.30 8329 1099 6170 814 1995 0.24 6733 1209 4987 896 1996 1997 0.13 3736 689 2767 510 1998 0.18 5181 968 3838 717 1999 0.20 5597 876 4146 649 2000 0.17 4898 663 3628 491 2001 0.23 6725 1310 4981 970 2002 0.29 8217 1022 6087 757 2003 0.27 7488 1452 5547 1076 2004 0.27 7729 1391 5725 1030 2005 0.21 5839 894 4325 662 2006 0.23 6564 836 4862 619 2007 0.34 9473 986 7017 730 2008 0.35 9857 1377 7302 1020 ICES Advice 2009, Book 6 151

6.4.14.4 Nephrops in Firth of Forth (FU 8) State of the stock The evidence from the UWTV survey suggests that the population has been at a relatively high level since 2003. The UWTV survey information, taken together with information showing stable mean sizes, suggest that the stock is being exploited sustainably. Reference points F Harvest Technical basis reference point ratio F 0.1 8.0% WKNEPH 2009 F max 13.7% WKNEPH 2009 (unchanged since 2009) Single-stock exploitation boundaries ICES advises on the basis of exploitation boundaries in relation to high long term yield and low risk of depletion of production potential that the Harvest Rate for Nephrops fisheries should not exceed F max. This corresponds to landings of no more than 1 567 tonnes for the Firth of Forth stock. Basis: Bias corrected survey index (2008) = 881 Rationale Harvest rate Landings 2010 (tonnes) 5.0% 572 F 0.1 8.0% 915 10.0% 1144 15.0% 1715 F max 13.7% 1567 20.0% 2287 F 2008 24.5% 2802 Management considerations To protect the stock in this Functional Unit, management is required to be implemented at the Functional Unit level. The advised landings for 2010 imply a reduction of 37% relative to the 2008 landings (2 500 t). ICES advice is for F max instead of F 0.1 because increased landings in earlier years have coincided with an increase in stock implying perhaps that the present level of exploitation could be sustainable. Even though in the longer term the differences in total catch are expected to be small, the move to F 0.1 as a target would imply significant initial reductions in catch. In this case a stepwise approach could be considered. A reduction of the catch corresponding to F max could be an intermediate step toward F 0.1 (as a proxy for F msy ). Alternatively, a constraint on the year to year change in catches as is typical of management plans and the Communication on Fishing Opportunities for 2010 [COM (2009) 224] might be considered. Nephrops discard rates in this Functional Unit are high and there is a need to reduce these and to improve the exploitation pattern. An additional reason for suggesting improved selectivity in this area relates to bycatch. It is important that efforts are made to ensure that other fish are not taken as unwanted bycatch in this fishery which uses 80mm mesh. Larger square mesh panels implemented as part of the Scottish Conservation Credits scheme should help to improve the exploitation pattern for some species such as haddock and whiting. Factors affecting the fisheries and the stock Landings from the Firth of Forth fishery are predominantly reported from Scotland, with very small contributions from England. The area is periodically visited by vessels from other parts of the UK. There is a risk that owing to fuel costs vessels which would normally fish further offshore will locate to inshore grounds. The Firth of Forth is close inshore and is of small geographic size so that significant influx of effort will have deleterious effects. Catches of marketable bycatch fish are small from this area and there are few other species in the area for vessels to target. 152 ICES Advice 2009, Book 6

Estimated discarding rates are 31% by number in the Firth of Forth in 2008. This arises from the use of mainly smallmeshed (80 mm) nets and the population size structure which appears to arise from slower growth. Local markets for small whole Nephrops are seasonally important. Changes in fishing technology and fishing patterns The Firth of Forth resident fleet contains numerous small boats which are generally restricted to more sheltered inshore waters. There are, however, observations of shifts of Nephrops fishing by larger vessels from the fleet to grounds such as the Devil s Hole ( an offshore ground not included as part of a Functional Unit). Scientific basis Data and methods The UWTV survey has been conducted annually since 1993 (no surveys in 1995 and 1997). Monthly market sampling and quarterly on-board observer sampling provides good coverage of length compositions. Potential bias in survey design has been detected and accounted for in the assessment this year (see Data and methods section at the start of section 6.4.14.) Information from the fishing industry The NSCFP survey (Figure 6.4.14.3) does not include specific information for the Firth of Forth. Uncertainties in assessment and forecast General comments are found at the start of section 6.4.14 Comparison with previous assessment and advice The perception of the stock in 2008 is very similar to that of the stock in 2007 The advice in 2008 was based on recent landings as the UWTV surveys were considered inappropriate to use as absolute indices of abundance. Following the outcome of the benchmark in 2009, the major concerns of the UWTV survey have been addressed and the survey is now considered a reliable estimate of absolute abundance.. The landings forecast for 2010 (<1 567 t) is considerably lower than for 2009 (<2500t). This is due to using F max as the target F for this stock in the current advice. ICES Advice 2009, Book 6 153

Table 6.4.14.4.1 Nephrops, Firth of Forth (FU 8). Single-stock exploitation boundaries (advice), management, and landings. Year ICES advice Recommended landings Firth of Forth (FU8) Recommended landings FU6+FU8 1992 ~4.6 1.8 1993 4.17 2.4 1994 4.17 1.9 1995 4.17 1.8 1996 4.17 1.7 1997 4.17 2.2 1998 4.17 2.1 1999 4.17 2.2 2000 4.17 1.8 2001 4.17 1.5 2002 4.17 1.3 2003 4.17 1.1 2004 4.17 1.7 2005 4.17 2.0 2006 No increase in effort - 2.4 2007 No increase in effort, harvest rate <15% 1.5 5.0 2.6 2008 No new advice, same as for 2007 1.5 5.0 2.5 2009 No increase in effort and recent average landings < 2.5 2.4 ICES Landings FU8 1) 2010 Harvest Rate no greater than that equivalent to fishing at F max Weights in 000 t. 1) Does not include discards. 2) It is not advised to manage these stocks as a single unit. < 1.6 -- 2) 154 ICES Advice 2009, Book 6

Landings (tonnes) Landings - International UK Scotland - All gears 3000 UK Scotland - Nephrops traw lers 2500 2000 International 1500 1000 500 0 1960 1970 1980 1990 2000 2010 Effort ('000 hours trawling) Effort - Scottish Nephrops trawlers 150 120 90 60 30 0 1960 1970 1980 1990 2000 2010 LPUE - Scottish Nephrops trawlers Mean sizes - Scottish Nephrops trawlers LPUE (kg/hour trawling) 50 40 30 20 10 0 1960 1965 1970 1975 1980 1985 1990 1995 2000 2005 2010 Mean size (mm carapace length) 42 38 34 30 Catch Mal < 35 mm CL Catch Fem < 35 Landings Mal < 35 Landings Fem < 35 26 Landings Mal > 35 Landings Fem > 35 22 1960 1970 1980 1990 2000 2010 Figure 6.4.14.4.1 Nephrops, Firth of Forth (FU 8). Long-term trends in landings, effort, lpues, and mean sizes of Nephrops. 1400 1200 Abundance (millions) 1000 800 600 400 Figure 6.4.14.4.2 200 0 1993 1994 1995 1996 1997 1998 1999 2000 2001 Year 2002 2003 2004 2005 2006 2007 2008 Nephrops, Firth of Forth (FU 8). Time-series of bias adjusted UWTV survey abundance estimates (in millions), with 95% confidence intervals, 1993 2008. ICES Advice 2009, Book 6 155

Figure 6.4.14.4.3 Nephrops, Firth of Forth (FU 8). Catch length frequency distribution and mean sizes (red line). 156 ICES Advice 2009, Book 6

Table 6.4.14.4.2 Nephrops, Firth of Forth (FU 8). Total landings (tonnes). Year All Nephrops gears combined Single rig Multirig Landings Effort LPUE Landings Effort LPUE Landings Effort LPUE 1981 945 42.6 22.2 945 42.6 22.2 na na na 1982 1138 51.7 22.0 1138 51.7 22.0 na na na 1983 1681 60.7 27.7 1681 60.7 27.7 na na na 1984 2078 84.7 24.5 2078 84.7 24.5 na na na 1985 1908 73.9 25.8 1908 73.9 25.8 na na na 1986 2204 74.7 29.5 2204 74.7 29.5 na na na 1987 1582 62.1 25.5 1582 62.1 25.5 na na na 1988 2455 94.8 25.9 2455 94.8 25.9 na na na 1989 1833 78.7 23.3 1833 78.7 23.3 na na na 1990 1901 81.8 23.2 1901 81.8 23.2 na na na 1991 1359 69.4 19.6 1231 63.9 19.3 128 5.5 23.3 1992 1714 73.1 23.4 1480 63.3 23.4 198 8.5 23.3 1993 2349 100.3 23.4 2340 100.1 23.4 9 0.2 45.0 1994 1827 87.6 20.9 1827 87.6 20.9 0 0.0 0.0 1995 1708 78.9 21.6 1708 78.9 21.6 0 0.0 0.0 1996 1621 69.7 23.3 1621 69.7 23.3 0 0.0 0.0 1997 2137 71.6 29.8 2137 71.6 29.8 0 0.0 0.0 1998 2105 70.7 29.8 2105 70.7 29.8 0 0.0 0.0 1999 2192 67.7 32.4 2192 67.7 32.4 0 0.0 0.0 2000 1775 75.3 23.6 1761 75.0 23.5 14 0.3 46.7 2001 1484 68.8 21.6 1464 68.3 21.4 20 0.5 40.0 2002 1302 63.6 20.5 1286 63.3 20.3 16 0.3 53.3 2003 1115 53.0 21.0 1082 52.4 20.6 33 0.6 55.0 2004 1651 63.2 26.1 1633 62.9 26.0 18 0.4 49.7 2005 1973 66.6 29.6 1970 66.5 29.6 3 0.1 58.8 2006 2437 61.4 39.7 2432 61.0 39.9 5 0.4 14.2 2007 2628 57.6 45.6 2607 57.1 45.7 21 0.5 43.2 2008 2435 52.2 46.6 2405 51.7 46.5 30 0.5 60.0 ICES Advice 2009, Book 6 157

Table 6.4.14.4.3 Nephrops, Firth of Forth (FU 8). Survey indices with and without bias adjustment. Values after 2002 have been adjusted for revised camera parameters Year Mean density Abundance 95% confidence interval Adjusted for bias 95% confidence interval burrows/m² millions millions millions millions 1993 0.72 655 167 555 142 1994 0.58 529 92 448 78 1995 1996 0.48 443 104 375 88 1997 1998 0.38 345 95 292 81 1999 0.60 546 92 463 78 2000 0.57 523 83 443 70 2001 0.54 494 93 419 78 2002 0.66 600 140 508 119 2003 0.99 905 163 767 138 2004 0.81 743 166 630 140 2005 0.92 838 169 710 143 2006 1.07 976 148 827 126 2007 0.90 816 156 692 132 2008 1.14 1040 350 881 297 158 ICES Advice 2009, Book 6

6.4.14.5 Nephrops in Moray Firth (FU 9) State of the stock The evidence from the UWTV survey suggests that the population is stable, but at a lower level than that evident from 2003-2005. The UWTV survey information, taken together with information showing stable mean sizes, suggest that the stock is being exploited sustainably. Reference points F Harvest Technical basis reference point ratio F 0.1 8.9% WKNEPH 2009 F max 16.6% WKNEPH 2009 (unchanged since 2009) Single-stock exploitation boundaries ICES advises on the basis of exploitation boundaries in relation to high long term yield and low risk of depletion of production potential that the Harvest Rate for Nephrops fisheries should not exceed F 2008. This corresponds to landings of no more than 1 372 tonnes for the Moray Firth stock. Basis: Bias corrected survey index (2008) = 478 Rationale Landings Harvest 2010 rate (tonnes) 5.0% 520 F 0.1 8.9% 926 10.0% 1040 F 2008 13.2% 1372 15.0% 1560 F max 16.6% 1727 20.0% 2080 Management considerations To protect the stock in this Functional Unit, management is required to be implemented at the Functional Unit level. A reduction of the catch corresponding to F 2008 can be considered as an intermediate step toward F 0.1 (as a proxy for F msy ). Alternatively, a constraint on the year to year change in TAC as is typical of management plans and the Communication on Fishing Opportunities for 2010 [COM (2009) 224] might be considered. There is a bycatch of other species in the Moray Firth area. It is important that efforts are made to ensure that unwanted bycatch is kept to a minimum in this fishery. Current efforts to reduce discards and unwanted bycatches of cod under the Scottish Conservation credits scheme, include the implementation of larger meshed square mesh panels and real time closures to avoid cod. Factors affecting the fisheries and the stock In the Moray Firth area the Nephrops stock inhabits a single continuous area of muddy sediment extending from north of Fraserburgh to Inverness. The Moray Firth Nephrops ground is located close to the Scottish coast and is exploited almost exclusively by UK vessels. Landings from this fishery are predominantly reported from Scotland, with very small contributions from England in the mid-1990s, but none recently. Regulations and their effects Discarding rates averaged over the period 2006 to 2008 for this stock were about 6% by number. This represents a marked reduction in discarding rate compared to the average for the period 2003 to 2005. This may arise from the increasing use of larger size meshes in the northern North Sea, although reduction in recruitment may also account for this change. ICES Advice 2009, Book 6 159

Scientific basis Data and methods UWTV survey estimates are available for 1993 1994 and from 1996 onwards. Length compositions from the commercial fishery are available from 1980. Potential bias in survey design has been detected and accounted for in the assessment this year (see Data and methods section at the start of section 6.4.14.) Uncertainties in assessment and forecast General comments are found at the start of section 6.4.14 Information from the fishing industry The NSCFP survey (Figure 6.4.14.3) does not include specific information for the Moray Firth. Comparison with previous assessment and advice The perception of the stock in 2008 is similar to that of the stock in 2007 The advice in 2008 was based on recent landings as the UWTV surveys were considered inappropriate to use as absolute indices of abundance. Following the outcome of the benchmark in 2009, the major concerns of the UWTV survey have been addressed and the survey is now considered a reliable estimate of absolute abundance. The landings forecast for 2010 (< 1 372 t) is considerably lower than for 2009 (< 1 800t). This is due to using the status quo F (F 2008 ) as the target F for this stock in the current advice. Table 6.54.14.5.1 Nephrops, Moray Firth (FU 9). Single-stock exploitation boundaries (advice), management, and landings. Year ICES advice Recommended landings Moray Firth (FU9) Recommended landings FU9+FU10 ICES landings FU9 1) 1987 2.0 1988 2.0 1989 2.6 1990 2.0 1991 1.5 1992 ~2.4 1.6 1993 2.4 1.8 1994 2.4 1.5 1995 2.4 1.3 1996 Status quo TAC 2.4 1.5 1997 Status quo TAC 2.4 1.4 1998 2.4 1.0 1999 2.4 1.0 2000 1.85 1.5 2001 1.85 1.4 2002 Catches to be maintained at the 2000 level 2.0 1.1 2003 Catches to be maintained at the 2000 level 2.0 1.1 2004 Catches to be maintained at the 2000 level 2.0 1.3 2005 Catches to be maintained at the 2000 level 2.0 1.6 2006 No increase in effort - 1.8 2007 No increase in effort, and harvest rate 2.4 2.64 1.8 below 15% 2008 No new advice, same as for 2007 2.4 2.64 1.5 2009 No increase in effort and recent average landings < 1.8 2010 Harvest Rate no greater than that equivalent to fishing at F 2008 < 1.4 -- 2) Weights in 000 t. 1) Does not include discards. 2) It is not advised to manage these stocks as a single unit. 160 ICES Advice 2009, Book 6

Landings (tonnes) Landings - International UK Scotland - All gears 3000 International 2500 2000 1500 1000 500 0 1960 1965 1970 1975 1980 1985 1990 1995 2000 2005 Effort ('000 hours trawling) Effort - Scottish Nephrops trawlers 100 80 60 40 20 0 1960 1965 1970 1975 1980 1985 1990 1995 2000 2005 LPUE - Scottish Nephrops trawlers Mean sizes - Scottish Nephrops trawlers LPUE (kg/hour trawling) 100 90 80 70 60 50 40 30 20 10 0 1960 1965 1970 1975 1980 1985 1990 1995 2000 2005 Mean size (mm carapace length) 42 38 Catch Mal < 35 mm CL 34 Catch Fem < 35 30 Landings Mal < 35 Landings Fem < 35 26 Landings Mal > 35 Landings Fem > 35 22 1960 1965 1970 1975 1980 1985 1990 1995 2000 2005 Figure 6.4.14.5.1 Nephrops, Moray Firth (FU 9). Long-term trends in landings, effort, lpues, and mean sizes of Nephrops. 1200 1000 Abundance (millions) 800 600 400 Figure 6.4.14.5.2 200 0 1993 1994 1995 1996 1997 1998 1999 2000 2001 Year 2002 2003 2004 2005 2006 2007 2008 Nephrops, Moray Firth (FU 9). Time-series of bias adjusted UWTV survey abundance estimates (in millions), with 95% confidence intervals, 1993 2008 ICES Advice 2009, Book 6 161

Figure 6.4.14.5.3 Nephrops, Moray Firth (FU 9), Catch length frequency distribution and mean sizes (red line). 162 ICES Advice 2009, Book 6

Table 6.4.14.5.2 Nephrops, Moray Firth (FU 9). Nominal landings as officially reported (tonnes). Year All Nephrops gears combined Single rig Multirig Landings Effort LPUE Landings Effort LPUE Landings Effort LPUE 1981 1298 36.7 35.4 1298 36.7 35.4 na na na 1982 1034 28.2 36.7 1034 28.2 36.7 na na na 1983 850 21.4 39.7 850 21.4 39.7 na na na 1984 960 23.2 41.4 960 23.2 41.4 na na na 1985 1908 49.2 38.8 1908 49.2 38.8 na na na 1986 1933 51.6 37.5 1933 51.6 37.5 na na na 1987 1723 70.6 24.4 1723 70.6 24.4 na na na 1988 1638 60.9 26.9 1638 60.9 26.9 na na na 1989 2102 69.6 30.2 2102 69.6 30.2 na na na 1990 1700 58.4 29.1 1700 58.4 29.1 na na na 1991 1284 47.1 27.3 571 25.1 22.7 713 22.0 32.4 1992 1282 40.9 31.3 624 24.8 25.2 658 16.1 40.9 1993 1505 48.6 31.0 783 28.1 27.9 722 20.6 35.0 1994 1178 47.5 24.8 1023 42.0 24.4 155 5.5 28.2 1995 967 30.6 31.6 857 27.0 31.7 110 3.6 30.6 1996 1084 38.2 28.4 1057 37.4 28.3 27 0.8 33.8 1997 1102 47.7 23.1 960 42.5 22.6 142 5.1 27.8 1998 739 34.4 21.5 576 28.1 20.5 163 6.3 25.9 1999 813 35.5 22.9 699 31.5 22.2 114 4.0 28.5 2000 1343 49.5 27.1 1068 39.8 26.8 275 9.7 28.4 2001 1188 47.6 25.0 913 37.0 24.7 275 10.6 25.9 2002 1526 35.5 43.0 649 27.2 23.9 234 7.9 29.6 2003 1718 41.1 41.8 737 25.3 29.1 135 3.6 37.5 2004 1818 36.9 49.3 1100 29.2 37.7 123 2.5 49.2 2005 1526 37.6 40.6 1309 34.0 38.5 217 3.6 60.3 2006 1718 41.1 41.8 1477 37.4 39.5 241 3.7 65.1 2007 1816 36.9 49.2 1502 32.4 46.4 314 4.5 69.8 2008 1443 30.1 47.9 1125 25.3 44.5 318 4.8 66.3 ICES Advice 2009, Book 6 163

Table 6.4.14.5.3 Nephrops, Moray Firth (FU 9). Survey indices with and without bias adjustment. Values after 2002 have been adjusted for revised camera parameters Year Mean density Abundance 95% confidence interval Adjusted for bias 95% confidence interval burrows/m² millions millions millions millions 1993 0.19 418.0 94 345 78 1994 0.39 850.0 213 702 176 1995 1996 0.26 563.0 109 465 90 1997 0.14 317.0 66 262 55 1998 0.18 391.0 115 323 95 1999 0.22 483.8 105 400 87 2000 0.212 466.8 118 386 98 2001 0.19 416.9 135 345 112 2002 0.29 629.7 146 520 121 2003 0.40 882.5 380 729 314 2004 0.35 757.5 225 626 186 2005 0.48 1051.8 239 869 198 2006 0.25 539.1 150 446 124 2007 0.29 641.6 189 530 157 2008 0.26 578.9 183 478 151 164 ICES Advice 2009, Book 6

6.4.14.6 Nephrops in Noup (FU 10) The advice for 2009 is biannual and valid for 2009 and 2010 (see ICES, 2008). Table 6.4.14.6.1 Nephrops, Noup (FU 10). Single-stock exploitation boundaries (advice), management, and landings. Year ICES advice Recommended landings Noup (FU10) Recommended landings FU9+FU10 ICES Landings FU10 1) 1987 0.04 1988 0.08 1989 0.08 1990 0.22 1991 0.19 1992 ~2.4 0.19 1993 2.4 0.38 1994 2.4 0.50 1995 2.4 0.28 1996 Status quo TAC 2.4 0.34 1997 Status quo TAC 2.4 0.32 1998 2.4 0.25 1999 2.4 0.28 2000 1.85 0.28 2001 1.85 0.18 2002 Catches to be maintained at the 2000 level 2.0 0.40 2003 Catches to be maintained at the 2000 level 2.0 0.34 2004 Catches to be maintained at the 2000 level 2.0 0.23 2005 Catches to be maintained at the 2000 level 2.0 0.17 2006 No increase in effort - 0.13 2007 No increase in effort, and recent average landings 0.24 2.64 0.15 2008 No new advice, same as for 2007 0.24 2.64 2) 0.17 2009 No increase in effort, and average landings 2003 < 0.24 2005 2010 No new advice, same as for 2009 < 0.24 -- 3) Weights in 000 t. 1) Does not include discards. 2) Based on a 15% harvest rate applied to UWTV survey abundance data. Includes Moray Firth (FU 9). 3) It is not advised to manage these stocks as a single unit. ICES Advice 2009, Book 6 165

6.4.14.7 Nephrops in Norwegian Deeps (FU 32) The advice for 2009 is biannual and valid for 2009 and 2010 (see ICES, 2008). Table 6.4.14.7.1 Nephrops in the Norwegian Deep (FU 32). Single-stock exploitation boundaries (advice), management, and landings. Year ICES advice Recommended Landings FU32 TAC Agreed 1 ICES Landings FU32 2) 1987 < 0.1 1988 < 0.1 1989 < 0.1 1990 0.2 1991 0.2 1992 0.2 1993 0.3 1994 0.8 1995 0.5 1996 1.0 1997 0.8 1998 0.8 1999 1.1 2000 1.1 2001 1.2 2002 1.2 No TAC agreed 1.2 2003 1.2 No TAC agreed 1.1 2004 1.5 1.0 0.9 2005 1.5 1.0 1.1 2006 No increase in effort - 1.3 1.0 2007 No increase in effort - 1.3 0.8 2008 No new advice, same as for 2007-1.3 0.7 2009 No increase in effort - 1.2 2010 No new advice, same as for 2009 - Weights in 000 t. Norwegian zone of Subarea IV. 1) TAC for EU vessels only. 2) Does not include discards. 166 ICES Advice 2009, Book 6

6.4.14.8 Nephrops off Horn s Reef (FU 33) The advice for 2009 is biannual and valid for 2009 and 2010 (see ICES, 2008). Table 6.4.14.8.1 Nephrops, FU 33 (Off Horn Reef). Single-stock exploitation boundaries (advice), management, and landings. Year ICES advice Recommended Landings FU33 ICES Landings FU33 1) 1992 0.87 1993 0.87 0.2 1994 0.87 0.1 1995 0.87 0.2 1996 0.87 <0.1 1997 0.87 0.3 1998 1.0 0.3 1999 1.0 0.7 2000 1.6 0.6 2001 1.6 0.8 2002 2.1 0.9 2003 2.1 0.9 2004 2.38 1.3 2005 2.38 1.1 2006 2.38 2) 1.3 2007 No increase in effort - 1.5 2008 No new advice, same as for 2007-1.4 2009 No increase in effort - 2010 No new advice, same as for 2009 - Weights in 000 t. 1) Does not include discards. 2) Includes Farn Deeps (FU6). ICES Advice 2009, Book 6 167

6.4.15 Herring in Division IIIa and Subdivisions 22 24 (Western Baltic spring spawners) State of the stock Spawning biomass in relation to precautionary limits Fishing mortality in relation to precautionary limits Fishing mortality in relation to high longterm yield Undefined Undefined Overfished NA Fishing mortality in relation to agreed target Comment In the absence of agreed reference points, the state of the stock cannot be evaluated. SSB has been stable in recent years but is expected to decline rapidly due to poor recruitment. Fishing mortality has been stable and is estimated at 0.37, well above the candidate for F msy. From 2004 onwards, recruitment has been declining and is now at a record-low. Management objectives There are no explicit management objectives for this stock. Reference points There are no precautionary approach reference points agreed for this stock. Yield and spawning biomass per Recruit F-reference points (2009): Fish Mort Yield/R SSB/R Ages 3-6 Average last 3 years 0.37 0.03 0.06 Fmax* - - - F0.1 0.23 0.03 0.09 Fmed 0.39 0.03 0.05 *Fmax is not well defined. Candidates for reference points consistent with high long-term yields and a low risk of depleting the productive potential of the stock are around F 0.1. Preliminary HCR evaluations are consistent with this view and have shown that candidates for F msy can be found in the region of F = 0.25 (see section 8.3.3.1). Single-stock exploitation boundaries ICES advises on the basis of exploitation boundaries in relation to long-term yield that fishing at the candidate Fmsy fishing mortality (0.25) implies catches in 2010 not larger than 39 800 t in the entire distribution area. 168 ICES Advice 2009, Book 6

ICES Advice 2009, Book 6 169 Short-term implications Outlook for 2010 Basis (for Western Baltic spring spawning herring WBSS): F(2009) = 0.29 [Catch constraint]; R 09-11 =GM(2003-2007)=2225 million; SSB(2009) = 142; catch (2009) = 45 a). Catches are for herring in Division IIIa and Subdivisions 22 24, see further in Section 6.4.16 on North Sea Autumn Spawning herring (NSAS). Catch options and results for WBSS herring only: Catch options for WBSS and NSAS herring: Division IIIa, Subdivisions 22-24 and Division IVaE Division IIIa and Subdivisions 22-24 1) 1) 22-24 III a IVaE SSB SSB % SSB 22-24 IIIa % TAC Catch F Fleet F Fleet C Fleet D Fleet A 2010 2011 change Catch Fleet F Fleet C Fleet D change Rationale 2010 Basis 2010 2) 3) 3) 4) 2010 5) Zero catch 0 F = 0.0 0 0 0 0 0 131 157 19% 0 0 0 0-100% High longterm yield 39.8 F sq *0.9 0.25 18.8 18.7 2.2 0.1 128 122-5% 50.8 18.8 26.2 5.8-31% Status quo 45.4 F sq *1.0 0.29 21.5 21.3 2.5 0.1 128 117-8% 57.9 21.5 29.8 6.6-21% 48.7 F sq *1.1 0.31 23.1 22.9 2.7 0.1 127 114-10% 62.3 23.1 32.1 7.1-15% 57.3 F sq *1.3 0.38 27.2 26.9 3.1 0.1 127 107-15% 73.3 27.2 37.7 8.4 0% 65.9 F sq *1.5 0.45 31.3 31.0 3.6 0.1 126 100-20% 84.3 31.3 43.4 9.6 15% Weights in 000 t a) assuming a utilisation of the TAC/bycatch ceiling of 97% (F-fleet), 52% (D-fleet) and 65% (C-fleet). 1) Ratio of herring catches between different fleets and areas in 2009 is based on the 2009 TACs (or bycatch ceiling in case of fleet D), ratio between the different herring stocks in IIIa is based on the 2008 catch ratios. The later ratio cannot be predicted and may therefore deviate significantly from the assumed ratio... 2) As in 2008 a catch of 0.1 t of WBSS herring taken in the Eastern North Sea is assumed. 3) For spring spawning stocks, the SSB is determined at spawning time and is influenced by fisheries between 1 st January and spawning time. 4) SSB (2011) relative to SSB (2010). 5) Catches (2010) relative to TAC 2009 (SD 22-24 + IIIa + IIIa bycatch ceiling = 27.2+37.7+8.4 = 73.3 kt). To derive the total herring catch for Division IIIa (right hand side of the table), predicted catches of NSAS (as advised in section 6.4.16) have to be added to the advised maximum catches of WBSS in the area. The total catch by fleet is only compatible with the advice for WBSS if the values given for NSAS are treated as maximum catches. Thus the resulting catch options were also used as constraints for catch options for the NSAS herring (Section 6.4.16). Note that the right hand side of the table is for illustrative purposes only and is not part of the ICES advice; the ratio of TACs between areas is not fixed and there are several options for TACs compatible with the removal of WBSS advised by ICES. Explanation on fleet coding: Area Fleet Description North Sea A Directed herring fisheries with purse-seiners and trawlers. Bycatches in industrial fisheries by Norway are included. B Bycatches of herring taken under EU regulations. Division IIIa C Directed herring fisheries with purse-seiners and trawlers. D Bycatches of herring caught in the small-mesh fisheries. Sub-Divisions 22-24 F All herring fisheries in Subdivisions 22 24. ICES Advice 2009, Book 6 169

Catch options for mixed stocks in Division IIIa based on short-term predictions for Western Baltic Spring- Spawning herring (WBSS) Catch options for the whole stock of Western Baltic Spring-Spawning herring (WBSS) can be partitioned into catches by area. Catches of WBSS herring in Division IIIa also imply catches of North Sea Autumn-Spawning (NSAS) herring which constitute part of the total catch in that area. ICES catch predictions versus management TAC ICES advises on catch options by fleet for the entire distribution of the two herring stocks separately, whereas herring is managed by areas cross-sectioning the geographical distribution of the stocks (see the following text diagram). The catch options for 2010 are based on the TAC proportions by fleet and area in 2009 and, for IIIa, on the observed stock composition (WBSS vs. NSAS) in catches taken in 2008. Short-term predictions are based on an expected catch in 2009 of 45 087 t of Western Baltic spring spawning stock taking into account the TACs by fleet for 2009, potential misreporting and the assumed proportion of Western Baltic spring spawning herring in the catches in Division IIIa. To make fleet wise catch options for the prediction year it is assumed that the TAC distribution by fleet in 2010 will be equal to 2009. It is also assumed that there will be allowed a subtraction of 20% of the Norwegian quota that is transferred to the A-fleet (as NSAS). Further it is assumed that each fleet catches its total TAC. Finally it is assumed that the 2008 proportions of WBSS by fleet hold for 2010. The proportions of WBSS in catches were 0.71 in the C- fleet, 0.37 in the D-fleet and 1.00 in the F-fleet and further a constant catch of 120 t of WBSS caught in the A-fleet in Division IVa East. Management considerations North Sea Autumn-Spawning and the Western Baltic Spring-Spawning herring stocks are exploited and managed simultaneously in Division IIIa. Hence, the management of the herring fisheries in Division IIIa influences both stocks. Recruitment of Western Baltic herring has been reduced by 15-35% annually from 2004 onwards. The estimated strength of the 2008 year class is the lowest of the whole times series, and amounts to only a quarter of the average. There is no indication that recruitment would return to the previous level in the near future. The poor year classes have not yet fully contributed to the SSB but will increasingly do so in the near future. In this situation, there is no alternative to reduce F significantly to avoid a drastic decline of the SSB. ICES has used the mean recruitment from 2003 2007 (year classes) for the short-term prediction which might be overly optimistic in the present situation. Factors affecting the fisheries and the stock Regulations and their effects Corrections for misreporting by area have been incorporated in the assessment. In recent years, ICES has calculated that a substantial part of the catch reported as taken in Division IIIa by fleet C was actually taken in Subarea IV. These catches have been allocated to the North Sea stock and accounted for under the A fleet. Regulations allowing quota transfers from Division IIIa to the North Sea were introduced as an incentive to decrease misreporting for the Norwegian part of the fishery. Recent Working Group estimates of 30% misreporting in Division IIIa may be underestimating the problem because not all countries supply this information to ICES. The quota for the C fleet and the bycatch quota for the D fleet (see above) are set for the NSAS and the WBSS stocks together. The implication for the catch of NSAS must also be taken into account when setting quotas for the fleets that exploit these stocks. 170 ICES Advice 2009, Book 6

Changes in fishing technology and fishing patterns There have been only minor changes in the fishery technology in recent years. Impact of the environment on the fish stock Herring in Division IIIa and Subdivisions 22 24 are migratory. There are feeding migrations from the Western Baltic into more saline waters of Division IIIa and the eastern parts of Division IVa. There are indications from parasite infections that yet unknown proportions of sub-stocks spawning at the southern coast in the Baltic proper may perform similar migrations. Western Baltic herring recruitment has been reduced by 15-35% annually from 2004 onwards and is now at a record low. North Sea herring, with which Western Baltic herring shares the same environment at least for part of the year, has also produced only very small year classes since 2002. In a recent recruitment analysis for different Baltic herring stocks, the Baltic Sea Index (BSI) reflecting Sea Surface Temperature (SST) was the main predictor for Western Baltic herring (Cardinale et al., in press). There are no indications of systematic changes in growth or age at maturity, and candidate key stages for reduced recruitment are probably the egg or the larval stage. The specific reasons for reduced egg or larval survival are not known. Further investigation of the causes of the poor recruitment will require targeted research projects. Scientific basis Data and methods The otolith microstructure method has been used to calculate the proportion of spring and autumn spawners caught in these areas for all catch and survey data in the period 1991 2008. An analytical FLICA assessment is based on catch data and the results of two acoustic and one larval survey. Information from the fishing industry VMS data confirm that area misreporting from the North Sea to the Skagerrak has declined in proportion with the reduction in reported landings. Identified misreported catch has been moved to the appropriate areas and are thus taken into account in the assessment. Uncertainties in assessment and forecast There is no firm basis to predict the fraction of NSAS in the catches by the C- and D-fleets. The proportions of the two stocks as well as the distribution pattern of the fishery in the Eastern North Sea and in Division IIIa changes dynamically year by year. This is probably influenced by the year class strength of the two stocks and their relative geographical distributions, as well as by fleet behavior reacting to herring availability and management decisions. The strength of a year class is not firmly estimated before the year class has been followed for 2 3 years. However, the introduction of a larval 0-group recruitment index (N20) in 2008 appears to contribute valuable and consistent information to the estimate of the 1-winter ringers in the assessment. Comparison with previous assessment and advice A benchmark assessment was carried out in 2008. The update assessment this year shows a reduction of 23% of the estimated fishing mortality in 2007 and a 21% increase for the SSB in 2007. However trends in recruitment and SSB are similar. In 2008 ICES advised an immediate reduction in F to candidate for Fmsy = 0.25. In the light of the continuing reduction of recruitment, the basis for the advice did not change. Source of information Report of the Herring Assessment Working Group for the Area South of 62 N, 17-25 March 2009 (ICES CM 2009/ACFM:03). Cardinale, M., Mölmann, C., Bartolino, V., Casini, M., Kornilovs, G., Raid, T., Margonski, P.,Raitaniemi, L., and Gröhsler, T. (in press). Climate and parental effects on the recruitment of Baltic herring (Clupea harengus membras) populations. Conditionally accepted by MEPS. ICES Advice 2009, Book 6 171

Table 6.4.15.1 Herring in Division IIIa and Subdivisions 22 24 (Western Baltic spring spawners). Single stock exploitation boundaries (advice), management and catches. Year ICES Advice Pred. catch corresp. to advice Agreed TAC IIIa 2 ICES catch of Stock 22 IIIa IV Total 24 1987 Reduction in F 224 218 102 59 14 175 1988 No increase in F 196 218 99 129 23 251 1989 TAC 174 218 95 71 20 186 1990 TAC 131 185 78 118 8 204 1991 TAC 180 155 70 112 10 192 1992 TAC 180 174 85 101 9 195 1993 Increased yield from reduction in F; reduction in 188 210 81 95 10 juvenile catches 186 1994 TAC 130 180 191 66 92 14 172 1995 If required, TAC not exceeding recent catches 168 192 183 74 80 10 164 1996 If required, TAC not exceeding recent catches 164 171 163 58 71 1 130 66 85 1 100 68 55 1 124 1997 IIIa: managed together with autumn spawners 22 24: if required, TAC not exceeding recent catches 1998 Should be managed in accordance with North Sea autumn spawners 1999 IIIa: managed together with autumn spawners 22 24: if required, TAC not exceeding recent catches 2000 IIIa: managed together with autumn spawners 22 24: if required, TAC not exceeding recent catches 2001 IIIa: managed together with autumn spawners 22 24: if required, TAC not exceeding recent catches 2002 IIIa: managed together with autumn spawners 22 24: if required, TAC not exceeding recent catches - 97 51 53 8 112-99 50 43 5 98 ~60 for Subdivs. 22 24 ~50 for Subdivs. 22 24 ~50 for Subdivs. 22 24 101 54 57 7 118 101 64 42 6 112 101 53 47 7 107 2003 Reduce F <80 101 40 36 2 78 2004 Separate management regime for this stock 91 42 24 7 77 <92 Reduce F 2005 Separate management regime for this stock 95 120 44 38 7 89 Status quo F 2006 Separate management regime for this stock 95 102 3 /47.5* 42 36 11 89 Status quo F 2007 Separate management regime for this stock 99 69 3 /49.5* Status quo F 40 28 1 68 2008 Separate management regime for this stock 71 51.7 3 /45* 43 25 0 68 Reduce F by 20% towards F 0.1 2009 Separate management regime for this stock < 32.8 37.7 3 /27.2* Reduce F to F = 0.25 2010 Separate management regime for this stock Reduce F to F = 0.25 <39.8 Weights in 000 t. 1 Catch in Subdivisions 22 24. 2 Including mixed clupeoid TAC and bycatch ceiling in small-mesh fishery. 3 Human consumption in Division IIIa, not incuding industrial bycatch or mixed clupeoids, but including North Sea Autumn Spawner catch in fleet C. * separate TAC for SD 22 24. 172 ICES Advice 2009, Book 6

Landings 250 Landings in 1000 t 200 150 100 50 0 1991 1993 1995 1997 1999 2001 2003 2005 2007 F(ages 3-6) 0.8 0.7 0.6 0.5 0.4 0.3 0.2 0.1 0.0 Fishing Mortality 1991 1993 1995 1997 1999 2001 2003 2005 2007 Recruitment in billions 7 6 5 4 3 2 1 0 Recruitment (age 0) 1991 1993 1995 1997 1999 2001 2003 2005 2007 Spawning Stock Biomass SSB in 1000 t 350 300 250 200 150 100 50 0 1991 1993 1995 1997 1999 2001 2003 2005 2007 2009 Figure 6.4.15.1. Herring in Subdivisions 22 24 and Division IIIa (spring spawners). Landings, fishing mortality, recruitment, and SSB. Estimates are shown in grey. 2009 recruitment taken as GM 2003 2007. ICES Advice 2009, Book 6 173

Stock - Recruitment Recruitment (age 0) in billions 7 6 5 4 3 2 1 0 0 50 100 150 200 250 300 350 SSB in 1000 t Yield and Spawning Stock Biomass per Recruit 0.035 0.35 0.03 0.3 Yield (dashed line) 0.025 0.02 0.015 0.01 0.25 0.2 0.15 0.1 SSB (line) 0.005 0.05 0 0 0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 Fishing Mortality (ages 3-6) SSB in 1000 t 350 300 250 200 150 100 50 Precautionary Approach Plot Period 1991-2008 0 0.0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 Fishing Mortality (ages 3-6) F-SSB 2008 Figure 6.4.15.2 174 Herring in Subdivisions 22 24 and Division IIIa (spring spawners). Stock recruitment, yield and SSB per recruit, precautionary approach. ICES Advice 2009, Book 6

Figure 6.4.15.3 Herring in Subdivisions 22 24 and Division IIIa (spring spawners). Historical performance of the assessment. The last data point for SSB is a prediction, for Recruitment the last data points is GM 03-07. ICES Advice 2009, Book 6 175

Table 6.4.15.2 Herring in Subdivisions 22 24 and Division IIIa (spring and autumn spawners). Landings ( 000 t). Year 1987 1988 1989 1990 1991 1992 1993 1994 1995 1996 1997 Skagerrak Denmark 105.0 144.4 47.4 62.3 58.7 64.7 87.8 44.9 43.7 28.7 14.3 Faroe Islands Germany Norway 1.2 5.7 1.6 5.6 8.1 13.9 24.2 17.7 16.7 9.4 8.8 Sweden 51.2 57.2 47.9 56.5 54.7 88.0 56.4 66.4 48.5 32.7 32.9 Total 157.4 207.3 96.9 124.4 121.5 166.6 168.4 129.0 108.9 70.8 56.0 Kattegat Denmark 46.6 76.2 57.1 32.2 29.7 33.5 28.7 23.6 16.9 17.2 8.8 Sweden 29.8 49.7 37.9 45.2 36.7 26.4 16.7 15.4 30.8 27.0 18.0 Total 76.4 125.9 95.0 77.4 66.4 59.9 45.4 39.0 47.7 44.2 26.8 Sub. Div. 22+24 Denmark 32.5 33.1 21.7 13.6 25.2 26.9 38.0 39.5 36.8 34.4 30.5 Germany 53.1 54.7 56.4 45.5 15.8 15.6 11.1 11.4 13.4 7.3 12.8 Poland 8.0 6.6 8.5 9.7 5.6 15.5 11.8 6.3 7.3 6.0 6.9 Sweden 7.8 4.6 6.3 8.1 19.3 22.3 16.2 7.4 15.8 9.0 14.5 Total 101.4 99.0 92.9 76.9 65.9 80.3 77.1 64.6 73.3 56.7 64.7 Sub. Div. 23 Denmark 0.8 0.1 1.5 1.1 1.7 2.9 3.3 1.5 0.9 0.7 2.2 Sweden 0.2 0.1 0.1 0.1 2.3 1.7 0.7 0.3 0.2 0.3 0.1 Total 1.0 0.2 1.6 1.2 4.0 4.6 4.0 1.8 1.1 1.0 2.3 Grand Total 336.2 432.4 286.4 279.9 257.8 311.4 294.9 234.4 231.0 172.7 149.8 Year 1998 (2) 1999 (2) 2000 2001 (5) 2002 (4) 2003 2004 2005 2006 (1,3) 2007 2008 (1) Skagerrak Denmark 10.3 10.1 16.0 16.2 26.0 15.5 11.8 14.8 5.2 3.6 3.9 Faroe Islands 0.4 0.0 Germany 0.7 0.5 0.8 0.6 0.5 1.6 Norway 8.0 7.4 9.7 3.5 4.0 Sweden 46.9 36.4 45.8 30.8 26.4 25.8 21.8 32.5 26.0 19.4 16.5 Total 65.2 53.9 71.5 47.0 52.3 42.0 34.1 48.5 31.8 26.9 26.0 Kattegat Denmark 23.7 17.9 18.9 18.8 18.6 16.0 7.6 11.1 8.6 9.2 7.0 Sweden 29.9 14.6 17.3 16.2 7.2 10.2 9.6 10.0 10.8 11.2 5.2 Total 53.6 32.5 36.2 35.0 25.9 26.2 17.2 21.1 19.4 20.3 12.2 Sub. Div. 22+24 Denmark 30.1 32.5 32.6 28.3 13.1 6.1 7.3 5.3 1.4 2.8 3.1 Germany 9.0 9.8 9.3 11.4 22.4 18.8 18.5 21.0 22.9 24.6 21.8 (6) Poland 6.5 5.3 6.6 9.3-4.4 5.5 6.3 5.5 2.9 5.5 Sweden 4.3 2.6 4.8 13.9 10.7 9.4 9.9 9.2 9.6 7.2 7.0 Total 49.9 50.2 53.3 62.9 46.2 38.7 41.2 41.8 39.4 37.6 37.5 Sub. Div. 23 Denmark 0.4 0.5 0.9 0.6 4.6 2.3 0.1 1.8 1.8 2.9 5.3 Sweden 0.3 0.1 0.1 0.2-0.2 0.3 0.4 0.7 0.3 Total 0.7 0.6 1.0 0.8 4.6 2.6 0.4 2.2 2.5 2.9 5.7 Grand Total 169.4 137.2 162.0 145.7 128.9 109.5 92.8 113.6 93.0 87.7 81.3 (1) (2) (3) (4) (5) (6) Preliminary data. Revised data for 1998 and 1999 Bold= German revised data for 2001 2000 tonnes of Danish landings are missing, see text section 3.1.2 The Danish national management regime for herring and sprat fishery in Subdivision 22 was changed in 2002 The total landings in Skagerrak have been updated for 1995-2001 due to Norwegian misreportings into Skagerrak. This value is incorrect but could not be corrected in subsequent calculations before the completion of the meeting. The correct value is 22.8 176 ICES Advice 2009, Book 6

Table 6.4.15.3 Herring in Subdivisions 22 24 and Division IIIa (spring spawners). Summary of the assessment. Year Recruitment SSB Landings Mean F Age 0 at spawning time Ages 3-6 thousands tonnes tonnes 1991 5003979 310543 191573 0.3576 1992 3652584 322123 194411 0.4762 1993 3109372 295303 185010 0.5439 1994 6182874 231273 172438 0.6894 1995 4050991 183178 150831 0.5121 1996 4472243 134412 121266 0.7007 1997 3991042 150554 115588 0.5097 1998 5585578 121510 107032 0.4919 1999 6439794 128418 97240 0.3730 2000 3444329 141946 109914 0.4661 2001 4448602 162715 105803 0.4537 2002 3057143 201961 106191 0.4102 2003 4039490 162065 78309 0.3944 2004 2655128 167171 76815 0.3577 2005 2226088 165281 88406 0.4073 2006 1813432 192109 90549 0.3959 2007 1259682 161537 68997 0.3576 2008 894443 159406 68484 0.3670 2009* 2225068 141824 Average 3607756 185965 118270 0.4591 * Recruitment is GM (2003 2007). SSB is predicted. ICES Advice 2009, Book 6 177

6.4.16 Herring in Subarea IV and Divisions IIIa and VIId (North Sea autumn spawners) State of the stock Spawning biomass in relation to precautionary limits Increased risk Fishing mortality in relation to precautionary limits Harvested sustainably Fishing mortality in relation to high longterm yield Overfished Fishing mortality in relation to agreed target Above target Comment Based on the most recent estimates of SSB and fishing mortality, ICES classifies the stock as being at risk of having reduced reproductive capacity and harvested sustainably. The SSB in autumn 2008 was estimated at 1.0 million t, and is expected to remain below B pa (1.3 million t) in 2009. F 2-6 in 2008 was estimated at 0.24, above the management target F 2-6 (for this state of the stock = 0.14). The year classes since 2002 are estimated to be among the weakest since the late 1970s. Management objectives In November 2008 EU-Norway have agreed on an adjusted management plan (see annex) taking account of recent poor recruitment. ICES has evaluated this management plan (WKHMP ICES CM 2008 ACOM:27) and concluded that the plan is consistent with the precautionary approach. Reference points Type Value Technical basis B lim 800 000 t < 0.8 million t; poor recruitment has been experienced B Precautionary pa 1.3 million t B trigger in the previous harvest control rule approach F lim not defined F pa F 0-1 = 0.12 F 2-6 = 0.25 Target Fs in the previous harvest control rule Targets F mt F 0-1 = 0.05 F 2-6 = 0.25 If SSB >1.5 million tonnes, B trigger (based on simulations) F 0-1 = 0.05 F 2-6 = 0.25 (0.15*(1500000-SSB)/700000) If SSB between 0.8 and 1.5 million tonnes (based on simulations) F 0-1 = 0.04 F 2-6 = 0.10 If SSB <0.8 million t (based on simulations) Precautionary reference points unchanged since 1999, target reference points since 2009. Yield and spawning biomass per Recruit F-reference points (2009): Fishing Yield/R SSB/R Mort Ages 2-6 average last 3 years 0.31 0.018 0.05 F max 0.47 0.013 0.024 F 0.1 0.13 0.011 0.075 F 35%SPR 0.16 0.012 0.065 HCR evaluation has shown than candidates for reference points which are consistent with high long-term yields and a low risk of depleting the productive potential of the stock are around the target values in the management plan. Single-stock exploitation boundaries ICES advises on the basis of the agreed EU Norway management plan. Following the agreed management plan implies catches of 164 300 t for fleet A and 10 400 t for fleet B in 2010 in the North Sea. Short-term implications Catch forecasts are presented below for different scenarios of sharing the catch amongst fleets, producing the total fishing mortality given in the table headings. The forecasts are based on an assumption of the fisheries in 2009, taking 178 ICES Advice 2009, Book 6

the TAC with an overshoot by the A-fleet of 13% corresponding to the overshoot seen in the last three years, and bycatches following the agreed management plan. The seven scenarios presented below are based on an interpretation of the harvest control rule or other options and show the range of options for differing overall exploitation rates. The distribution of catches among the fleets is only illustrative, and other options with similar overall exploitation rates are possible: a) No fishing; b) Catches that are estimated lead to SSB>Bpa in 2011; c) A 15% decrease in A fleet in TAC between 2009 and 2010; d) The EU-Norway management plan with larger catches of approximately 40% for the C and D fleet e) The EU Norway management plan; f) A roll over TAC from 2009 to 2010 of 171 kt for the A fleet; g) A 15% increase in A fleet in TAC between 2009 and 2010; Since the current management plan only stipulates overall fishing mortalities for juveniles and adults, making fleet-wise predictions for four fleets that are more or less independent provides different options for 2010. The consequence of other combinations of catch options can be explored on request. Outlook assuming a TAC constraint for fleet A in 2009 Basis: Intermediate year (2009) with catch constraint R 09 (ICA)=32832 million; R 10-11 =GM(YC 2001-2007)=21465 million F fleet A F fleet B F fleet C F fleet D F 0-1 F 2-6 Catch fleet A Catch fleet B Catch Fleet C Catch fleet D SSB 2009 0.184 0.021 0.006 0.004 0.04 0.189 194.2 7.4 6.5 2.7 971 Scenarios for prediction year (2010) F Fleet A F-VALUES BY FLEET AND TOTAL CATCHES BY FLEET RESULTS F fleet B F fleet C F fleet D F 0-1 F 2-6 Catch fleet A Catch fleet B Catch fleet C Catch fleet D SSB SSB 2010 1) 2011 %SSB change 2) %TAC change fleet A 3) a 0 0 0 0 0 0 0 0 0 0 1133 1497 +32% -100% b 0.094 0.022 0.003 0.004 0.033 0.097 110.2 7.0 5.0 2.5 1063 1300 +22% -36% c 0.126 0.033 0.005 0.006 0.049 0.131 145.4 10.4 7.4 3.7 1040 1238 +19% -15% d 0.144 0.028 0.007 0.008 0.050 0.149 162.6 9.0 10.5 5.3 1027 1206 +17% -5% e 0.144 0.033 0.005 0.006 0.050 0.148 164.3 10.4 7.4 3.7 1027 1209 +18% -4% f 0.150 0.033 0.005 0.006 0.050 0.155 171.0 10.4 7.4 3.7 1023 1198 +17% 0% g 0.174 0.033 0.005 0.006 0.051 0.179 196.7 10.4 7.4 3.7 1007 1160 +15% +15% Weights in 000 t. Shaded areas are considered not in accordance with the precautionary approach. All numbers apply to North Sea autumn-spawning herring only. 1) For autumn spawning stocks, the SSB is determined at spawning time and is influenced by fisheries between 1 st January and spawning. 2) SSB 2011 relative to SSB 2010. 3) Calculated landings 2010 relative to TAC 2009. Fleet definitions: Fleet A: Directed herring fisheries with purse-seiners and trawlers (32 mm minimum mesh size) in the North Sea. Bycatches in the Norwegian industrial fisheries are included. Fleet B: Herring taken as bycatch in the small-mesh fisheries in the North Sea under EU regulations (mesh size less than 32 mm). Fleet C: Directed herring fisheries in Skagerrak and Kattegat with purse-seiners and trawlers (32 mm minimum mesh size). Fleet D: Bycatches of herring caught in the small-mesh fisheries (mesh size less than 32 mm) in Skagerrak and Kattegat. ICES Advice 2009, Book 6 179

Management considerations A reduction in fishing mortality to close to the target fishing mortality is expected to be achieved in 2009 (Figure 6.4.16.1). The SSB is expected to increase slightly both in 2010 and further in 2011, indicating that the current management has the potential to reverse the decline in the stock and stabilize it above the present level. The 2008 year class is estimated to be within the range of recent low recruitments. ICES assumes that the recruitment will remain at the low level. Delay in implementing substantial reductions in catch by not following the management plan has resulted in the SSB being at greater risk of being below B lim and lower catches (Figure 6.4.16.3). Landings of herring taken in the North Sea but reported from other areas such as Divisions IIa and IIIa and from Division VIaN have increased in 2008 compared to 2007. The total amount of catch in excess of the TAC in the human consumption fishery has increased as a proportion of the TAC to 17% (35 000 t). Management of the autumn-spawning herring must be considered together with the Western Baltic Spring-Spawning herring. The options selected for the C- and D-fleets are compatible with the advised exploitation of Western Baltic Spring Spawners assuming a catch for 2010 of 39800 tonnes (see Section 6.4.7) and are 7.4 and 3.7 thousand tonnes of North Sea autumn spawning herring for C and D fleets respectively. Downs herring The sub-tac for Divisions IVc and VIId was established for the conservation of the spawning aggregation of Downs herring. The Downs herring has returned to its pre-collapsed state and is now again a major component of the stock. It is probable that exploitation of Downs herring has been relatively high. In the absence of data to the contrary ICES proposes that a share of 11% of the total North Sea TAC (average share 1989 2002) would still be appropriate for Downs herring. Management plan evaluations The new management plan has been evaluated and the plan is consistent with the precautionary approach. Impact of fisheries on the ecosystems Herring is considered to have a major impact on most other fish stocks as prey and predator and is itself prey for seabirds and sea mammals. Herring spawning and nursery areas, being near the coasts, are particularly sensitive and vulnerable to anthropogenic influences. The most serious of these is the increasing extraction of marine sand and gravel and the development of wind farms on existing and historic spawning beds. The human consumption fisheries for herring are considered relatively clean, with little bycatch of other fish and almost no disturbance to the seabed. The limited evidence from observer programmes suggest that discarding of herring is not wide-spread. Juvenile herring are bycaught in the industrial fisheries.. Factors affecting the fisheries and the stock Regulations and their effects In EU waters, slippage and high grading of herring is now prohibited in the North Sea herring fishery (EC Council Reg No 43/2009) as long as the fish are above minimum landing size and quota is available. The consequences of new regulation are unknown but to thought have little impact on the catch estimates. In the Norwegian purse seine fisheries, slipping is permitted under conditions where the fish is assumed to be viable (likely to survive). This rule is currently under revision. High grading and discarding is not permitted. Changes in fishing technology and fishing patterns. There have been no major changes to fishing technology and fishing patterns of the fleets that target North Sea herring. Impacts of the environment on the fish stock North Sea herring has recently produced six poor year classes in a row, which has never been observed before at this SSB. Indications suggest that the 2008 year class has is slightly higher but still lies within the bounds of the recent series of poor year classes. The survival of the larvae has been poor (Payne et al., 2009). The specific reasons for this are not known. The trends in herring recruitment are similar to the warming of the water on the spawning grounds and changes in the hydrography. These changes may be linked to the AMO (Atlantic Multidecadal Oscillation), and they are also associated with changes in the zooplankton community. Further investigation of the causes of the poor recruitment will require targeted research projects.scientific basis 180 ICES Advice 2009, Book 6

Data and methods The stock assessment and projections used data from the landings and from four survey time-series of North Sea herring. Each of these surveys targets a different life stage of the herring. The landings and catch-at-age data is collated from Subarea IV and Divisions VIId and IIIa. Some national catch estimates were corrected for unallocated and misreported catch. Denmark and Norway provided information on bycatches of herring in the industrial fishery. These are the main countries conducting these fisheries. Information from the fishing industry Representatives from the pelagic industry after the ICES expert group express concern that for the last 2-3 years the fishermen s observations of the abundance of juvenile herring in the Eastern, Central and Southern part of the North Sea were higher than anticipated given the results of the assessment. The working group has found underestimation of the 2007 year class and corrected for this in the current assessment, however, other year classes are still estimated at the same low level. Uncertainties in assessment and forecast ICES carried out a benchmark assessment of the North Sea autumn-spawning herring stock in 2006, checking the appropriate use of the survey indices and catch. The present assessment is an update of the bench mark assessment. Surveys show slightly divergent signals. The occurrence of misreported and unallocated catches leads to uncertainties in the assessment. The overall assessment gives a consistent basis for advice (Figure 6.4.16.4). There is no evidence that discarding of herring is a major problem at present for the estimation of population dynamics or conservation of North Sea herring. Comparison with previous assessment and advice The assessment is consistent with the assessment of 2008. The new assessment has revised the size of the 2007 year class but it is still estimated as poor and comparable with the other recent year classes. The basis advice is different from last year. Last year ICES advised to implement a new management plan, this year it advises to follow the new management plan. Source of information Report of the Herring Assessment Working Group for the Area South of 62 N, 17 25 March 2009. ICES CM 2009/ACOM:03). Report of the Workshop on Herring Management Plans (WKHMP). ICES CM 2008/ACOM:27. Payne MR, Hatfield EMC, Dickey-Collas, M, Falkenhaug, T, Gallego, A, Gröger, J., Licandro, P, Llope, M, Munk, P, Röckmann, C, Schmidt, JO & Nash, RDM (2009). Recruitment in a changing environment: the 2000s North Sea herring recruitment failure. ICES J Mar Sci. 66: 272-277 ICES Advice 2009, Book 6 181

Table 6.4.16.1 Herring caught in the North Sea (Subarea IV and Division VIId). Single stock exploitation boundaries (advice), management and catch/landings. Year ICES Advice Predicted catch corresp. to advice Agreed TAC 1 Bycatch ceiling Fleet B ICES Lndgs. 4 IV, VIId ICES Catch 5 IV, VIId ICES Catch Autumn spawners IIIa, IV, VIId 1987 TAC 610 600 625 625 792 1988 TAC 515 530 710 710 888 1989 TAC 514 514 669 717 787 1990 TAC 403 415 523 578 646 1991 TAC 423 420 537 588 657 1992 TAC 406 430 518 572 716 1993 No increase in yield at F > 0.3 340 1 430 495 540 671 1994 No increase in yield at F > 0.3 346 1 440 463 498 571 1995 Long-term gains expected at lower F 429 1 440 510 516 579 1996 50% reduction of agreed TAC 2 156 1 156 3 44 207 233 275 1997 F = 0.2 159 1 159 24 175 238 264 1998 F(adult) = 0.2, F(juv)< 0.1 254 1 254 22 268 338 392 1999 F(adult) = 0.2, F(juv)< 0.1 265 1 265 30 290 333 363 2000 F(adult) = 0.2, F(juv)< 0.1 265 1 265 36 284 346 388 2001 F(adult) = 0.2, F(juv)< 0.1 See scenarios 265 36 296 323 363 2002 F(adult) = 0.2, F(juv)< 0.1 See scenarios 265 36 304 353 372 2003 F(adult) = 0.25, F(juv)=0.12 See scenarios 400 52 414 450 480 2004 F(adult) = 0.25, F(juv)=0.1 See scenarios 460 38 484 550 567 2005 F(adult) = 0.25, F(juv)=0.1 See scenarios 535 50 568 639 664 2006 F(adult) = 0.25, F(juv)=0.12 See scenarios 455 43 490 511 515 2007 Bring SSB above B pa by 2008 See scenarios 341 32 361 388 407 2008 F(adult) = 0.17, F(juv)=0.08 (MP) See scenarios 201 19 228 245 258 2009 Adopt one of the new proposed HCRs See scenarios 171 16 2010 F(adult) = 0.15, F(juv)=0.05 (MP) See scenarios Weights in 000 t. 1 Catch in directed fishery in IV and VIId. 2 Revision of advice given in 1995. 3 Revised in June 1996, down from 263. 4 Landings are provided by the working group and do not in all cases correspond to official statistics. 5 ICES catch includes unallocated and misreported landings, discards, and slipping. 182 ICES Advice 2009, Book 6

Figure 6.4.16.1 Herring in Subarea IV, Divisions VIId & IIIa (autumn spawners), stock summary. Fishing mortality is expressed as averages over ages 2 6 (dots) and 0 1 (line). B pa (B trigger in the previous Harvest control rule) and B lim, F pa 2-6 and F pa 0-1 are shown. Recruitment is expressed as one year olds (0 winter ring). ICES Advice 2009, Book 6 183