Single-stock exploitation boundaries

Considering the options below, ICES advises on the basis of exploitation boundaries in relation to precautionary limits that fishing grounds that are known to be commercially depleted should be closed to fishing while at non-depleted fishing grounds fishing should only be allowed in 2010 if analysis of real-time monitoring indicates that the stock can be rebuilt to B_pa by 2011

Exploitation boundaries in relation to high long-term yield, low risk of depletion of production potential and considering ecosystem effects

The management of sandeel fisheries should implement measures to prevent depletion of local aggregations, particularly in areas where predators congregate.

Exploitation boundaries in relation to precautionary limits

ICES recommends that fishing grounds that are known to be commercially depleted should be closed to fishing until there is evidence from monitoring programmes that local populations have recovered. On other fishing grounds, a fishery should only be allowed in 2010 if analysis of real-time monitoring indicates that the stock can be rebuilt to B_pa by 2011.


Table 6.4.22.1 Sandeel in Subarea IV. Single stock exploitation boundaries (advice), management and catch.

Year	Single-stock exploitation boundaries / from 2004 onwards ICES Advice	Catch corresponding to exploitation boundaries / advice	TAC 3	ICES Catch
1987	No advice1; No advice2			825
1988	No advice1; No advice2			893
1989	No advice1; No advice2			1039
1990	No advice1; No advice2			591
1991	No advice1; No advice2			843
1992	No advice1; No advice2			855
1993	No advice1; No advice2			579
1994	No advice1; No advice2			786
1995	Can sustain current F1; No advice2			918
1996	Can sustain current F			777
1997	Can sustain current F			1138
1998	Can sustain current F		1000	1004
1999	Can sustain current F		1000	735
2000	Can sustain current F		1020	699
2001	Can sustain current F		1020	862
2002	Can sustain current F		1020	811
2003	No increase in F		918	326
2004	Exploitation to be kept below level of 2003. Adjustment to be made conditional on the abundance of the 2003 year class	-	826	362
2005	Exploitation to be kept below level of 2003. Adjustment to be made conditional on the abundance of the 2004 year class	-	661	172
2006	The fishery should remain closed until information is available which assures that the stock can be rebuilt to Bpa by 2007.	-	300	288
2007	The fishery should remain closed until information is available which assures that the stock can be rebuilt to Bpa by 2008.	-	1734	206
2008	The fishery should only be allowed if monitoring information is available and shows that the stock can be rebuilt to Bpa by 2009.	-	4005	335
2009	The fishery should only be allowed if monitoring information is available and shows that the stock can be rebuilt to Bpa by 2010	-	400
2010	The fishery should only be allowed if monitoring information is available and shows that the stock can be rebuilt to Bpa by 2011	-
Weights in ‘000 t. 1 Southern stock component. 2 Northern stock component. 3 Set for zone IIIa, EC waters of Division IIa and Subarea IV. 4 EU and Norway, set at 30 June 2007. 5 EU and Norway, set at 23 July 2008.

There are no explicit management objectives for this stock.

Management considerations

The high natural mortality of sandeel and the few year classes in the fishery make the stock size and catch opportunities largely dependent on the size of the incoming year classes.

If a real-time management using an escapement strategy is applied in 2010, the escapement target should be defined so that the SSB reaches at least B_pa in 2011. Fishing grounds that are known to be commercially depleted should be closed to fishing until there is evidence that local populations have recovered.

ICES recommends that future management should take account of the spatial structure of sandeels. Sandeel management in the North Sea is based on the assumption that there is a single stock when there is strong evidence of a number of spatially distinct (sub-)stocks. The full stock structure of sandeel in the North Sea, however, remains unclear. It is known that (sub-)stocks on the Viking/Bergen Banks, in the western North Sea off Scotland, and the (separately-managed) Shetland stock are all distinct. The present knowledge on defining (sub-)stocks off south-western Norway and in the southern North Sea is too limited to recommend specific management measures for 2010 which can take the full stock structure into account.

Impacts of fisheries on the ecosystems

Local depletion of sandeel aggregations at a distance less than 100 km from seabird colonies may affect some species of birds, especially black-legged kittiwake (Rissa tridactyla) and sandwich tern (Sterna sandvicensis), whereas the more mobile marine mammals and fish may be less vulnerable to local sandeel depletion. In the light of studies linking low sandeel availability to poor breeding success of kittiwake, all commercial fishing in the Firth of Forth area has been prohibited since 2000, except for a short-term fishery in May and June of each year for stock monitoring purposes.

A major function of sandeels in the North Sea ecosystem is the provision of food to predators, including fish, marine mammals, and seabirds. The management objectives should ensure that the stock remains high enough to provide food for predator species and prevent depletion of local aggregations, particularly in areas of predator concentration. The sandeel fishery in the area off the Scottish coast that was closed to sandeel fishery in 2000, should continue to be closed in 2010 in view of the current low productivity of the sandeel (sub-)stock in this area and to provide, as far as possible, a food supply to dependent predators. In other areas of the North Sea, avoidance of depletion at a local scale will help take account of the function of sandeels in the ecosystem.