10/8/2014 Setting TACs for IIIa herring EU Herring TACs David C.M. - PDF document

10/8/2014 Setting TACs for IIIa herring EU Herring TACs David C.M. Miller, IMARES PAC WG I, Den Haag, 1 October 2014 Biological advice Biological units JUVENILES  ICES provides advice on catch levels that can be sustained by particular fish stocks  Each stock is considered to be a unique (self-contained) biological unit ● New fish enter the stock through reproduction of ADULTS Fish stock adult fish in the stock (SPAWNERS) ● Catching fish removes them from the stock and, if LARVAE uncontrolled, may affect the amount of reproduction in future EGGS Biological units Biological units  Fish stocks may have multiple  In the North Sea, Kattegat and Skagerrak there are two spawning areas main biological stocks:  Fish change their ● North Sea Autumn Spawners (NSAS) distribution ● Western Baltic Spring Spawners (WBSS) during the year  Adult and juvenile fish may  Though some sub-stock structure exists within these be found in stocks, they are biologically separated from each other different ● Spawn in different areas at different times of year locations 1

10/8/2014 Biological advice vs management NSAS and WBSS herring stocks IV IIIa 22-24  Biological advice is given as the amount of catch that a STOCK can sustain  Management is given as the amount of catch that can be taken in each AREA WBSS NSAS Stocks may be found in more than one management area Herring in IIIa Herring in IIIa: TACs  There is no single biologically unique herring stock in IIIa Mix ● Herring in this area are a mix of NSAS and WBSS NSAS herring WBSS  Therefore advice for  Different fleets operating in different areas catch fish catches in this area from one or both of the stocks needs to consider the development of both the NSAS and WBSS herring stocks TAC transfers Dividing stock TACs between management areas ???% ?% ???% ?%  The WBSS herring TAC is divided in  In addition, up to two: 50% of the IIIa TAC NSAS TAC NSAS ● 50% -> IIIa TAC can be transferred to ● 50% -> 22-24 fisheries in area  Evaluations will be IV conducted to  This happens IV IIIa IV IIIa 50% 50% determine what after the NSAS TAC WBSS TAC WBSS proportion of the and WBSS TACs NSAS TAC should have been split to be allocated to IIIa determine the IIIa 22-24 50% 22-24 50% TAC 2

10/8/2014 Herring in IIIa: TACs End  We can separate out (afterwards) how much of the catch in IIIa was NSAS and how much was WBSS Questions?  This can be used to determine what proportion of each TAC should be allocated to IIIa. e.g.: Total Catch Catch NSAS Catch NSAS Year NSAS (C-fleet,IIIA) % (C-fleet,IIIA) + IV flex % 2006 498970 11650 2.3 17158 3.4 2007 386690 16370 4.2 20096 5.2 2008 244920 9250 3.7 11344 4.6 2009 161900 5060 3.1 6078 3.7 2010 173850 11980 6.9 12895 7.4 2011 218090 6610 3.0 21610 9.9 2012 422450 7760 1.8 30260 7.2 3.6 5.9 3