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The Cod Day - Science. Coby Needle, Nick Bailey, Rui Catarino, Steven Holmes Marine Laboratory Aberdeen. Outline. North Sea cod West of Scotland cod Future developments. WoS cod – stock area. WoS cod – official landings. WoS cod – catches. 2011 Removals = 6.36 kt
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The Cod Day - Science Coby Needle, Nick Bailey, Rui Catarino, Steven Holmes Marine Laboratory Aberdeen The Cod Day Marine Laboratory, Aberdeen, 2 October 2012
Outline • North Sea cod • West of Scotland cod • Future developments
WoS cod – catches 2011 Removals = 6.36 kt Landings = 0.52 kt (8%), discards = 5.84 kt (92%)
WoS cod – surveys • Available surveys: • ScoGFS-WIBTS-Q1: 1985–2010 • Became UKSGFS-WIBTS-Q1 in 2011 • ScoGFS-WIBTS-Q4: 1996-2009 • Became UKSGFS-WIBTS-Q4 in 2011 • IGFS-WIBTS-Q4 • Only ScoGFS-WIBTS-Q1 used in assessment • 2013 assessment: Too soon to use UKSGFS (& stock subject to 1.5% bycatch rule).
WoS cod – surveys Q4 2010 Q4 2011
WoS cod – Int. effort TR1 = Trawl gear with mesh ≥ 100mm
WoS cod – Int. effort TR2 = Trawl gear with mesh ≥ 70mm & < 100mm
WoS cod – Int. effort LL = Long Lines
WoS cod – Int. effort GN = Gill nets & entangling nets
WoS – TR1 landings COD HADDOCK ANGLER SAITHE
WoS – TR1 & TR2 landings WHITING NEPHROPS
WoS cod – assessment • Assessed using the TSA method • Includes ScoGFS-WIBTS-Q1 survey, landings & discards • Landings 1995-2005 not used (suspected as biased) • No survey data for 2011-2012. • TSA - same basic approach as SAM model but developed in house (Rob Fryer)
Unlike N Sea F reduction only related to previous year Reduction depends on prediction of SSB at start of TAC year: 25% reduction in F if SSB < Blim 15% reduction in F if Blim < SSB < Bpa Min(10% reduction in F or F=0.4) if SSB > Bpa But 20% limit to changes in TAC But But 25% TAC reduction if stock unhealthy yet ‘data poor’ Also – ICES has never accepted management plan as precautionary WoS cod – Management plan
MSY approach MSY framework: TAC = 30 t MSY transition: TAC = 270 t But because SSB << Blim advice was for zero catch WoS cod – Advice