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

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

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)

some key issues

• S. mentella vs. S. marinus

• Stock identification of S. mentella

• connection between NEAtl & NWAtl stocks and fisheries

• Pelagic / Demersal components

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

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

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: ?

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.

Data: 5. Social

• Unknown

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

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.

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 62N 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

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

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)