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DeepFishMan Case Study 4: North East Atlantic Oceanic redfish

DeepFishMan Case Study 4: North East Atlantic Oceanic redfish. IMR: Benjamin Planque, Kjell Nedreaas, Daniel Howell MRI: Klara Jakobsdóttir, Thorsteinn Sigurdsson,. Biological Background (1). ?. Biological Background (2). Slow growth, 50% mature at age 13, max age ~75.

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DeepFishMan Case Study 4: North East Atlantic Oceanic redfish

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  1. DeepFishMan Case Study 4:North East Atlantic Oceanic redfish IMR: Benjamin Planque, Kjell Nedreaas, Daniel Howell MRI: Klara Jakobsdóttir, Thorsteinn Sigurdsson,

  2. Biological Background (1) ?

  3. Biological Background (2) Slow growth, 50% mature at age 13, max age ~75

  4. Biological Background (3) • viviparous species, mating and larval extrusion take place in different time/areas, • links between continental slope, Norwegian Sea and Barents Sea components are poorly known • Maybe multiple stocks (Norwegian Sea, Barents Sea, Svalbard), but this is still largely unexplored

  5. The Fisheries • No directed trawl fishery • Bycatch limits • Pelagic fishery in international waters since 2004 • Current landings around 10,000t • Directed demersal and pelagic fishery • Current landings around 16,000t (deep-sea) and 17,000t (oceanic)

  6. some key issues • S. mentella vs. S. marinus • Stock identification of S. mentella • connection between NEAtl & NWAtl stocks and fisheries • Pelagic / Demersal components

  7. Data: 1. Catch statistics • Catch: Catch statistics available 1986-2008 (except 1988), Russian data available prior to 1986 • Effort: Russian effort available 1975-2002 for 2 demersal trawler fleets (BMRT/PST), Norway effort needs to be collated, data available 1986-2008, Pelagic Fishery in Norwegian Sea (2006-), Standardised effort data (1988-) from Kaspersen (2008) • Fleets: 2 Russian demersal fleets, Norway demersal factory trawler, international Pelagic fleet • Catch/Effort/Landings in Iceland EEZ 1978-2008, logbook data by haul 1990-2008. Data prior to 1978 not split by species

  8. Data: 2. Biology • Life cycle: Data readily available (with the limitations mentionned earlier) • Biol. param: readily available • Stock structure: currently managed as one unit. Morphometric and otolith shape analysis provide (yet) equivocal evidence. • Ecology: some information on predators & preys (needs to be collated), long failure in recruitment still unexplained

  9. Data: 3. Biodiversity • Bycatch: can be analysed from Pelagic fisheries logbooks and surveys since 2006, bycatch in the early stage of the Norwegian demersal fishery maybe extracted from Fiskeridirektoratet reports, Iceland logbook data (1990-2008) • Benthos: see above • VMEs: see above • Fishing impact: ? • Ecosystem function: ?

  10. Data: 4. Economy • Fish prices: 1988-2008 from Norwegian Seafood Export Council (Kaspersen, 2008) • Fishing costs: 1988-2008 (Kaspersen, 2008, requires validation) • Investment? • All information for S. mentella and S. marinus combined.

  11. Data: 5. Social • Unknown

  12. Data: 6. Assessment (1) • Method used: no analytical assessment, XSA last tried in 2003. Current assessment is based in data from several surveys in the Barents Sea, Svalbard, and Norwegian slope and coast + recent data in the Norwegian Sea and catch statistics • Length distribution: available • Catch@age: available (ALK) • CPUE: same as effort data

  13. Data: 6. Assessment (2) • Survey data: back to 1980 depending on the surveys • Model planned: Gadget • Possible bonus: Bayesian model (Aannes et al 2007), XSA, proto-moments, others, tested using Gadget as an operational model > Aanes, S., Engen, S., Sæther, B.-E., Aanes, R., 2007. Estimation of the parameters of fish stock dynamics from catch-at-age data and indices of abundance: can natural and fishing mortality be separated? Can. J. Fish. Aquat. Sci. 64, 1130-1142.

  14. Data: 7. Management • Procedure: Assessment by ICES/AFWG, regulations set by Norwegian authorities in EEZ, by NEAFC in international waters. • Regulation: Directed trawl fisheries for S. mentella is forbidden in EEZ north of 62N and in the Svalbard area. Bycatches regulated (i.e. 3 juvenile redfish per 10 kg shrimp, 15% max bycatch in trawl fishery, both redfish species combined). Area closures. Pelagic fishery in international waters is managed by NEAFC since 2007 and an agreed TAC of 10,500 t was set in 2009

  15. Deliverables • Case study report • Data transfer towards WP3, WP4, WP5, WP6, WP7 • Gadget model development in WP4 • Interaction with WP4-WP7 ICES links • Benchmark assessment planned in AFWG in 2011 • Monitoring recommendations to PGNEACS/PGRS

  16. Overview surveys • 1st quarter: • Joint Norw-Rus demersal (incl. Acoustics) winter survey Barents Sea (1986- ) • 2nd quarter: • PGNAPES (2007- ) • Russian acoustic survey on spawning grounds-Kopytov area (1991-2000). Konstantin, incl. Those years covering Malang Bank-Spitbergen • Norw. trawl-acoustic survey 62N-70N on spawning grounds (1992, 2009), • Russian eggs- and larvae surveys, Lofoten-Kola, April-July (1959-1993), • Some years with Norw. postlarvae surveys (1985-1990) • 3rd quarter: • Joint Norw-Rus Ecosystem survey (demersal incl. Acoustics) Barents Sea and Svalbard (2004- 2008), some years only Svalbard (1982-2002) • 0-group (1965 -) • International Norwegian Sea pelagic acoustic survey (2007 -) • 4th quarter: • Russian demersal survey Barents Sea and Svalbard (1982 -) • Norw. trawl-acoustic survey 62N-70N (2008)

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