The Spatial and Temporal Distribution of Salmon and the Pelagic Fisheries in the North- East Atlantic: A Potential for By-catch?

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2 The Spatial and Temporal Distribution of Salmon and the Pelagic Fisheries in the North- East Atlantic: A Potential for By-catch? Marianne Holm 1, Árni Ísaksson 2, Jan Arge Jacobsen 3, Lars Petter Hansen 4, Sigurður Guðjónsson 5, Niall O Maoileidigh 6 and Sumarliði Óskarsson 2.

3 Affiliations 1 Institute of Marine Research, P.O. Box 1870 Nordnes, NO Bergen, Norway 2 Salmonid Fisheries and Ecosystem Management, Directorate of Fisheries, Dalshrauni 1, Hafnarfjörður, Iceland 3 Faroe Marine Research Institute, P.O. Box 3051, FO-110 Torshavn, Faroe Islands 4 Norwegian Institute for Nature Research, P.O.Box, 5685 Sluppen, NO-7485 Trondheim, Norway 5 Marine Institute, Furnace, Newport, Co. Mayo, Ireland 6 Institute of Freshwater Fisheries, Keldnaholt, 112 Reykjavik, Iceland

4 Sources of information Research surveys Tag recoveries Ices Working group reports (WGNAS. WGHMSA, SGBYSAL 2004 & 2005) SALSEA National screening programmes

5 History & Background - Salmon by-catches reported in various commercial fisheries at least 30 years -LATE 1990-TIES: Post-smolts and mackerel taken together in great numbers in Norwegian (surface trawl) research catches in June-July in Norwegian Sea - Overlap between post-smolt distribution and the mackerel fishery in 2 nd & 3 rd quarters in the Norwegian Sea : Unofficial Reports of large numbers of adult salmon taken in herring catches in the northernmost part of the Norwegian Sea : NASCO asked ICES WG on North Atlantic Salmon to look into the issue. - ICES Study Group on By-catches of Salmon in Pelagic Fisheries (SGBYSAL) in opearation in ICES NASCO SALMON SUMMIT

6 Quick look at distribution of salmon

7 CPUE of postsmolts, Colour scale indicates nrs per hour. Dot = trawl haul. Temporal scale of distribution of catches to the left

8 Distribution of post molt, CPUE, trawl hours in 2008 (left) and 2009

9 Swed Distribution of adults: Tag recoveries from the Faroes fisheries Iceland Faroes Norway

10 Post smolt sizes AREA WEEKS WEEKS WEEKS WEEKS Western UK & Faroes -Shetland Trench areas No data cm Fjords and coast of Norway Norwegian Sea south Norwegian Sea North Mean ~ 11.5 cm (West and Mid- Norway) -- ~ cm (Northern Norway) cm cm cm cm cm --

11 Potential overlap areas : Salmon & pelagic fisheries

12 RESULTS: Mapping excercise-salmon & Pelagic fisheries, week 23 Salmon, right panel; Mackerel, left (SGBYSAL report, 2005) ICES NASCO SALMON SUMMIT

13 Distribution: Salmon (right) & Mackerel fisheries (left), week 26 ICES NASCO SALMON SUMMIT

14 Distribution: Salmon (right) & Mackerel fisheries (left), week 29 ICES NASCO SALMON SUMMIT

15 Distribution: Salmon (right) & Mackerel fisheries (left), week 32 ICES NASCO SALMON SUMMIT

16 Fishing & surveying

17 Icelandic expandable pelagic trawls used for herring fishing and a typical multi-gear vessel, which is usually about 70 meters in length. Also shown is the size of the vessel in proportion to the size of the largest trawl Trawls close to the surface ICES NASCO SALMON SUMMIT

18 ICES NASCO SALMON SUMMIT Scientific survey method

19 Tab Summary of screening of commercial catches in NEA countries & salmon found, p. 45 Country Screening of commercial catches Biol. Sampling of pelagic species Salmon found Salmon found Germany Yes No Yes No Faroes No No Yes No Iceland Yes Yes Yes yes Ireland No No Yes No Netherlands Yes Yes Yes No Norway No No Yes yes Russia Yes Yes Yes yes UK Yes No Yes No ICES NASCO SALMON SUMMIT

20 Results from SGBYSAL Very large variation in estimated number of post smolts intercepted. Depending on data sets used=> range 15 individuals to 1,8 millions Estimates carried forward to calculations by SGBYSAL group in 2005 ranged from 0,0002 (Russian observer based data) post smolts per tonne of mackerel These estimates based on Russian research surveys.

21 Changes in fisheries since SGBYSAL Mackerel fishery now also occurring within the Faroes and Icelandic EEZs New methods : pair trawling in Faroes

22 New information from national screening programmes at Iceland and the Faroes

23 Number of Salmon as By-catch per month in ICES-rectangles from May through October 2010

24 Number of Salmon as By-catch per month in ICES-rectangles from May through October 2011

25 Number of Salmon as By-catch in ICES-rectangles in 2010 and 2011 also showing recovered Salmon Tags

26 Marine assignments Iceland (courtesy of John Gilbey, Data credits, Kristinn Ólafsson & Sigurður Guðjónsson)

27 Results of screening for salmon at Iceland, 2010 and 2011, estimates of number of salmon per tonnes of catch Landed Mackerel AND HERRING t Recorded Salmon, no Salmon bycatch, no per 1000 t Landed Mackerel AND HERRING t Recorded Salmon, no Salmon bycatch, no per 1000 t 35403* 169 4, ** 200 7,0** * 34 % mackerel in catches ** 63% mackerel

28 Salmon by-catch in the Faroese mackerel fishery in Estimates from screening mackerel catches delivered at the only land based factory Kollafjørð Pelagic during the fishing season Month in 2011 No of vessels No salmon Screened catch (t) Salmon per 1000 t Total catches (t) Total bycatch May June July August September Total ESTIMATE FOR TOTAL CATCH: 1.5 salmon per 1000 t mackerel

29 Summary and conclusions The screenings performed enable at least minimum estimates of salmon intercepted, but much by-catch information comes from unofficial sources, making quantification very difficult. The increase in by-catch reports during the last few years seems related to a change in the distribution of the mackerel fisheries Possibly also the use of increasingly larger and more efficient gear contribute to the bycatches.

30 The screenings for salmon indicate without doubt that salmon are intercepted in the commercial fisheries, and that this interception at times in certain areas can be larger than anticipated earlier

31 So, What to do? ICES NASCO SALMON SUMMIT

32 Management issues Surveys at processing plants for fish for human consumption and screening of the catches on board commercial fishing vessels are strongly recommended, but, Scientifically valid quantitative information can only be obtained by controlled experiments using commercial fishing methods. Gear and behaviour studies might help in solving some of the problems The by-catch records/samples add valuable information on the ecology of salmon at sea

33 Thanks To - the organisers for the invitation - numerous persons for valuable pieces of information