Herring in the southern Irish Sea, Celtic Sea and South West of Ireland, Pelagic trawl

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1 Herring in the southern Irish Sea, Celtic Sea and South West of Ireland, Pelagic trawl Content last updated 31st May 2018 Stock: Herring (Clupea harengus) in divisions 7.a South of North, 7.g h, and 7.j k (Irish Sea, Celtic Sea, and southwest of Ireland) Management: EU Herring in the southern Irish Sea, Celtic Sea and South West of Ireland, Pelagic trawl Overview Herring (Clupea harengus) is a pelagic schooling species that migrates between spawning, wintering and feeding grounds. Juveniles shoal close inshore while adults are found more offshore to depths of up to 200m. Herring spawn in coastal areas on gravel substrates, making them vulnerable to anthropogenic activity such as wind farms construction and gravel extraction. Herring is one of the dominant planktivorous fish and is an important prey item for predatory fish, marine mammals and seabirds. Herring can reach 40cm in length and have a maximum lifespan of 10 years, although most herring range between 20-30cm and are less than 7 years. Herring to thesouthern Irish Sea, Celtic Sea and South West of Ireland, comprise both autumn and winter spawning components. For the purpose of stock assessment and management these areas have been combined since Some juveniles of this stock are present in the Irish Sea for the first year or two of their life. Juveniles, which are believed to have originated in the Celtic Sea move to nursery areas in the Irish Sea before returning to spawn in the Celtic Sea. Stock Status less risk more risk The stock status of Herring in southern Irish Sea, Celtic Sea and South West of Ireland, has been scored a high risk. The spawning-stock biomass (SSB) has been decreasing significantly since its peak in 2011, and is now below MSY Btrigger and close to Blim. The fishing mortality (F) has increased since 2008 and is now above FMSY. Recruitment has been below average since Management less risk more risk The management of herring in divisions 7a, 7g-h, and 7j-k has been scored a very low risk. Evaluations conducted in 2015 by ICES show that the management strategy is precautionary. The TAC has been set in accordance with the management strategy since ICES is requested by the EC to provide advice based on the MSY approach and to include the management strategy as a catch option. Bycatch less risk more risk The bycatch risk of this fishery has been scored a very low risk. This is because the bycatch is negligible and the impact on Endangered, Threatened or Protected (ETP) species is very small, there are a number of measures in place to reduce bycatch. Habitat less risk more risk The habitat risk of the pelagic pair trawl fishery has been scored a very low risk. This is because there is no interaction of the gear with seafloor habitats. This is because appliances fitted to the head rope allow close monitoring of the distance from the sea bed. This is to avoid any damage to the net. Outlook Type Current Risk Status Outlook Reason Stock High Stable/ Improving There are concerns that the assessment is underestimating the actual stock size. Given the precautionary nature of the management regime this would be expected to improve the stock going forward. Management Very low Stable Management is in place which is considered precautionary. Bycatch Very Low Stable This is because the bycatch is negligible and the impact on Endangered, Threatened or Protected (ETP) species is very small, there are a number measures in place to reduce bycatch. Habitat Very low Stable This is because appliances are fitted to the head rope allowing close monitoring of the distance from the sea bed. This is to avoid any damage to the net.

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3 Stock Status Details less risk more risk Time-trends The spawning stock biomass (SSB) but, it has been decreasing significantly since its peak in The fishing mortality (F) has been increasing since 2008 placing the stock at risk. Recruitment has been below average since 2013 (ICES, 2017). Figure 1. Herring in divisions 7.a South of N, 7.g h, and 7.j k. Summary of the stock assessment. The assumed recruitment is unshaded and the forecast SSB value is designated by a grey diamond. The shaded areas on the F and SSB plots represent 95 % confidence intervals (ICES 2017). Stock structure and recruitment The herring (Clupea harengus) to the southern Irish Sea, Celtic Sea and South West of Ireland, comprise both autumn and winter spawning components. The majority of winter spawning fish found in adult aggregations in the Irish Sea are considered to be fish that were spawned in the Celtic sea (Beggs et al, 2008). Some juveniles of this stock are also present in the Irish Sea where they move to nursery areas for the first year or two of their life before returning to the Celtic Sea to spawn. This has been verified through tagging studies (Molloy, et al 1993) and studies examining otolith microstructure (Brophy and Danilowicz, 2002). Also it was concluded that Bantry Bay which is in 7j, was a nursery ground for fish of south coast (7g) origin (Molloy, 1968) In addition, larvae from the spawning grounds in the western part of the Celtic Sea were considered to be transported to the south west (division 7j) (ICES, 1982). Data gaps and research priorities Herring spawn in coastal areas on sandy and gravel substrates, making them vulnerable to anthropogenic activities such as gravel extraction and the development of coastal wind farms. In general, advice regarding the use of spawning grounds for human activities is precautionary and need to consider mitigation measures to avoid a negative impact on spawning. Further research is still required to gather information on particular spawning grounds so that more detailed and specific advice can be provided. There is limited knowledge on the present rate of discarding, but it is considered to be negligible. Besides discarded catches, considerable loss of herring may also occur during catch processing, e.g. flushing of tanks and slippage from the net. Little information is available about the amount of this loss, but it is thought to be large (van Helmond and van Overzee, WD to ICES 2014a, WD02). Effort should be made to maintain observer coverage across fleets that catch a substantial proportion of pelagic fish and to report on these issues. The 2014 and 2015 acoustic survey estimates were not used in the assessment (ICES, 2015b, 2016b) as the survey did not cover the entire distribution area of the stock. In 2016 the area coverage problem was solved. Since 2014, herring were observed close to the bottom, and unreliably estimated by the acoustic survey. The current assessment cannot deal with this change in estimation of herring by the survey, and changes to the assessment methodology are required. This means that the assessment may not adequately track recent stock development. The latest assessment shows retrospective downward revision of previous stock sizes. This is primarily due to the inclusion of the low 2016 acoustic survey index (ICES 2017). The Celtic Sea Herring Management Advisory Committee (CSHMAC) is very concerned about the annual acoustic survey which forms part of the stock assessment. The CSHMAC considers that the survey has been producing unrealistic low abundance estimates in recent years. The catching sector noted in 2016 that similar to the previous two years fish have remained very tight on the bottom of the sea and are spread out over a large area, which presents challenges in terms of them being picked up by the acoustic survey (ICES 2017). Beggs, S., Schon, P.J., McCurdy, W, Peel., J., McCorriston, P., McCausland, I (2008). Seasonal origin of 1 ring+ herring in the Irish Sea (VIIaN) Management Area during the annual acoustic survey. Working Document to the herring assessment working group Brophy, D., and Danilowicz, B.S., Tracing populations of Atlantic herring (Clupea harengus L.) in the Irish and Celtic Seas using otolith microstructure. ICES Journal of Marine Science, 59(6): ICES (1982). Report of the Herring Assessment Working Group South of 62ºN (HAWG) Part 2 of 2. Copenhagen, ICES: 18 pp. ICES (2014a). Report of the Herring Assessment Working Group for the Area South of 62 N (HAWG), March 2014, Copenhagen, Denmark. ICES CM 2014/ACOM:06. Molloy, J. (1968). Herring Investigations on the Southwest Coast of Ireland, ICES CM:68/H:14 Molloy, J., Barnwall, E., and Morrison, J., (1993). Herring tagging experiments around Ireland, Fishery Leaflet 7 pp ICES (2014b). Herring in Subarea IV and Divisions IIIa and VIId (North Sea autumn spawners). In Report of the ICES Advisory Committee, ICES Advice 2014, Book 6, Section

4 ICES (2016) Herring (Clupea harengus) in divisions 7.a South of North, 7.g h, and 7.j k (Irish Sea, Celtic Sea, and southwest of Ireland). ICES Advice Book ICES (2017) Herring (Clupea harengus) in divisions 7.a South of N, 7.g h, and 7.j k (Irish Sea, Celtic Sea, and southwest of Ireland). ICES Advice June 2017 Van Helmond, A.T.M. and van Overzee, H.M.J. (2014). Estimates of discarded herring by Dutch pelagic freezer fishery in WD to HAWG 2014, WD02.Van Helmond, A.T.M. and van Overzee, H.M.J. (2014). Estimates of discarded herring by Dutch pelagic freezer fishery in WD to HAWG 2014, WD02.

5 Management Details less risk more risk TAC Information Catch 2016 (t) Advised Catch 2017 (t) Agreed TAC 2017 (t) Advised Catch 2018 (t) < Advised and agreed catches ICES predictions indicate that this level of catch will be close to fishing mortality at precautionary levels (Fpa) rather than the ICES FMSY approach. This implies a slower recovery of this stock, compared to the ICES FMSY catch option. Evaluations conducted in 2015 by ICES (ICES, 2015a, 2015c) show that the management strategy is precautionary. The TAC has been set in accordance with the management strategy since ICES is requested by the EC to provide advice based on the MSY approach and to include the management strategy as a catch option (ICES 2017). Stock harvesting strategy Celtic Sea herring is assessed annually by means of an age structured model. The stock assessment is based on time-series of international fishery landings, age composition of the catches, and indices of abundance from an acoustic survey. The catches of Celtic Sea herring have been below the ICES advice in recent years. In recent years this fishery has been prosecuted entirely by Ireland. The fishery is now managed by the Irish Celtic Sea Herring Management Advisory Committee according to a Management Plan that has been evaluated as precautionary by ICES. This plan has been the de-facto management plan for the stock for 2012 and subsequent years. It is not enshrined in law because it has yet to be considered for approval by the European Parliament. Surveillance and enforcement The Irish Sea Fisheries Protection Agency (SFPA) was established on 1st January 2007 and is responsible for all monitoring, control and surveillance (MCS) within Irish waters, in conjunction with the Irish Naval Service. There is a high degree of enforcement and control in the Celtic Sea herring fishery (in accordance with commission regulation (EC) No 1542/2007 on landing and weighing procedures for herring, mackerel and horse mackerel) meaning almost 100% inspection of landings, regular inspections at sea, and fleet activity is monitored by aerial surveillance and through a satellite mediated VMS (Vessel Monitoring System). Where considered appropriate, more detailed and focused inspections and investigations are undertaken, combining information already collected with direct observation (off-loading and weighing of all catch) and inspection of further documentation. At processing plants, all landings must pass into the plant via weighbridges which have been calibrated, sealed and certified. The fish pass via a de-waterer and limited tolerance is allowed for water. In Ireland pelagic landings are typically transported via lorry to the processing plant (as opposed to direct pumping from ship to plant as is more typical in places like Norway and Scotland), the same basic principle of certified weighing of all landings applies. This secure weighing of all pelagics entering processing plants allows inspectors the opportunity to undertake mass-balance exercises (a complete audit of a product from one vessel going into a plant, and product coming out of a plant). This is typically done to each vessel at least once a year, and each plant several times a year. Such activity forms the backbone of the Common Fisheries Policy (CMP) Monitoring Control and Surveillance (MCS) system, and performance of this system against national and CFP targets, including details of infringements and prosecutions, is reported on an annual basis. These activities are coordinated through the EU Fisheries Control Agency based now based in Vigo, Spain. The new EU registration of buyers and sellers legislation, although not directly targeted at the pelagic sector, has also contributed to a major cultural shift within the industry, and there is now a sense of confidence on the part of the SFPA that strong systems, checks and balances are now in place to quickly identify and punish any illegal activity. As a result there is a widespread belief that non-compliance is no longer a major problem in the Irish pelagic industry. New regulations, which implement the EU control regulations in Ireland, are currently being drafted in Ireland these look set to continue the high level of enforcement and control in Irish pelagic fisheries such as Celtic sea herring (MSC Sustainable Fisheries). ICES 2015a Report of the Herring Assessment Working Group for the Area South of 62 o N, March ICES CM 2015/ACOM: 06 ICES 2015b Report of the Benchmark Workshop on West of Scotland Herring (WKWEST). ICES CM 2015/ ACOM: 34 ICES (2017) Herring (Clupea harengus) in divisions 7.a South of N, 7.g h, and 7.j k (Irish Sea, Celtic Sea, and southwest of Ireland). ICES Advice June 2017 MSC SUSTAINABLE FISHERIES Public Comment Draft Report CSHMAC Celtic Sea Herring. November 2011

6 Bycatch Details less risk more risk Targeting and behaviour The trawl used by the Irish fleet is designed and rigged to fish in mid-water, including in the surface water. Mid-water trawl is a well-aimed fishing activity. Suitable shoals or aggregations of herring are identified following the target species fishing procedure contained in the Irish voluntary Seafood Environmental Management System (SEMS). The fish shoals are located by eco-sounder and sonar (CSHMAC, 2015). Evidence of bycatch risk The capture of herring using pelagic trawls is a highly effective process that characteristically features an extremely low level of capture of non-target species. A range of information is available on the capture of non-target species in this fishery. Official catch statistics that are generated from on board EU logbooks is the primary source of information. This is cross referenced with sales notes, landing declarations and reports of landings inspections. Species that may be retained in the fishery as evidenced by landings statistics are mackerel and horse mackerel, both of which are pelagic species that may be mixed in with herring shoals at extremely low (negligible) levels. Results from scientific studies indicate that the overwhelming volume of captured biomass is of the target species (upwards of 99%). A wide range of species can be captured including some demersal fish such as whiting and cod. In particular, it is indicated that whiting may be captured in many hauls, along with Celtic Sea cod. Actual quantities of retained species captured however are highly likely to be very low and is considered incidental. All indications are that instances of capture of cetacean in the pelagic trawl fishery for Celtic Sea are very rare. This belief is largely based on the interpretation of data from a total of 403 days of monitoring of pelagic trawl fisheries that have been carried out in Ireland under Council Regulation 812 of 2004 as well as evidence form scientific and discard observer studies in this and other fisheries. This fishery presents a low risk of direct impacts to populations of ETP species in the Celtic Sea. Mitigation measures There are a number of management measures in place that are considered effective in minimising bycatch of non-target species (Pair trawl reference, CSHMAC, 2015). A range of measures are in place that collectively can be considered a strategy which minimises impacts on Endangered, Threatened or Protected (ETP) species, including legislation making unnecessary capture or killing illegal, designation of special areas of conservation, implementation of Council Regulation 812 of 2004 and voluntary onboard recording and reporting of ETP interactions while engaged in the herring fishery. CSHMAC, CSHMAC Celtic Sea Herring [ [Date accessed: 31-Dec-15] MSC SUSTAINABLE FISHERIES Public Comment Draft Report CSHMAC Celtic Sea Herring. November 2011

7 Habitat Details less risk more risk Gear effects, targeting and behaviour Depth transducers on the head rope give an accurate indication of net height from the seabed, enabling vessels to fish within approximately 2m of the seabed, whilst ensuring that there is no impact on bottom habitats or structures. No part of the trawl is designed to come in contact with the sea bed and any accidental contact with the seabed would typically result in expensive damage to the net, as these are considerably lighter than demersal trawl net. Evidence of habitat risk The fishery is highly unlikely to interact with any known sensitive seabed habitats such as deep water corals (which occur off the continental shelf to the west of Ireland, well away from the area where the fishery is prosecuted). The pelagic fishing gear used in the Celtic Sea herring pelagic trawl fishery is not designed to come into contact with the sea bed. Skippers have good control over the position of the net and the use of technology reduces the likelihood of any encounters with the seabed. A net monitor (sonar) with a transducer actually on the net enables skippers to accurately fish to within a couple of meters of the seabed without making contact. There is far less danger of gear loss in pelagic fisheries than in demersal trawl fisheries. This is partially due to the lack of contact with the seabed, but also because the nets are far lighter. For example, were a demersal trawl net to become entangled in a biogenic reef structure for instance, the heavy ground chain would be slow to break and then only after serious damage was likely to have been inflicted on the structure. By contrast, any pelagic net entangled in such a way would more easily break and be recovered, albeit in a damaged state. Mitigation measures Measures to minimise seabed/ fishing gear interactions are in place across the fleet and include the use of sophisticated electronics, including depth sounders, sonars and trawl monitoring systems. Scanning forward looking sonars on all vessels reveal seabed depth and topography for up to 1.5 miles ahead of the vessels, meaning that there is sufficient advance warning of changes in depth or seabed obstructions to allow altering of course or raising of the gear. Rapid changes to the depth of the net can be made directly from the wheelhouse via the winches. All vessels use trawl-monitoring sensors. Sensors are attached to the net and wheelhouse monitors display data in relation to the spread and height of the net opening, depth of the footrope of the net and the clearance between the footrope and the seabed. CSHMAC, CSHMAC Celtic Sea Herring [ [Date accessed: 31-Dec-15] MSC SUSTAINABLE FISHERIES Public Comment Draft Report CSHMAC Celtic Sea Herring. November 2011 All content 2018 Seafish. Origin Way, Europarc, Grimsby, DN37 9TZ. This page created on 20th August 2018 at 03:17am.