Coastal Sea Ecology
IMPRESS: Interactions between the marine environment, predators and prey
Implications for sustainable sandeel fisheries
The industrial lesser sandeel Ammodytes marinus fishery is the largest single species fishery in the North Sea. Sandeels are also a major prey of top predators such as seabirds. The fishing industry contests the view that its activities have a negative impact on top predators. However, species such as the black-legged kittiwake Rissa tridactyla have suffered a series of poor breeding seasons while the fishery has been operating. Therefore, detailed research on predator-prey interactions and the role of hydrography is needed to understand the ecosystem dynamics that the fishery is operating in, so that fisheries managers can be given the best advice possible on choosing options that take account of wildlife as well as commercial interests.
Previous research has shown that seabird breeding success is significantly reduced in the years when there are few sandeels available to the fishery in June (findings from the European Union (EU) project ELIFONTS - Effects of Large-scale Industrial Fisheries on Non-Target Species, 1997-1999). There is also evidence that fine-scale differences in the timing of peak sandeel availability influences reproductive output: breeding success is lower when the peak of availability is early. This effect may be due to annual variations in the timing of sandeel life history events – in particular the onset of burying behaviour in one-year-old fish, and the metamorphosis of sandeels hatched in the current year.
The findings from ELIFONTS played a key role in the EU fisheries ministers’ decision to adopt a precautionary approach. They banned fishing for sandeels in a 20,000 sq.m band of sea down the east coast of Britain in 2000. In that year, the breeding success of black-legged kittiwakes bounced back to pre-fishery levels. At face value this suggests that closing the fishery had an immediate positive effect on kittiwake productivity. However, data on the timing of sandeel availability showed that peak availability occurred late that year. Therefore it was unclear how much of the apparent recovery was due to the absence of fishing pressure and how much was due to environmental factors. We need to know more about the way changes in physical environmental factors affect sandeel demography.
IMPRESS has been designed to take a bottom-up approach, to determine the effect of climate and hydrography on temporal and spatial patterns in sandeel abundance and on the foraging performance of seabirds. It is a multi-disciplinary programme funded by the EU, and CEH collaborates with other organisations in the following areas:
Research at CEH has concentrated on assessing diet and breeding success, and equipping birds with a new generation of miniaturised data loggers, which will provide detailed records of the the birds' physical environment, including foraging location and temperature/depth profiles. Prey intake rate has been measured in different hydrographic conditions. Analyses have been carried out on long-term, historical biotic and abiotic data. The predator study species are black-legged kittiwake, common guillemot Uria aalge, European shag Phalacrocorax (Stictocarbo) aristotelis and Northern gannet Morus bassanus. Findings have been published in peer-reviews journals, together with multi-chapter contributions to “Top predators in marine ecosystems: their role in monitoring and management” (CUP; Eds I.L. Boyd, S. Wanless & C.J. Camphuysen)
Daunt, F., Wanless, S., Greenstreet, S.P.R., Jensen, H., Hamer, K.C. & Harris, M.P. (2008) The impact of sandeel fishery closure in the northwestern North Sea on seabird food consumption, distribution and productivity. Canadian Journal of Fisheries and Aquatic Sciences, 65, 362-381
Skov, H. Humphreys, E., Garthe, S., Geitner, K., Grémillet, D., Hamer, K.C., Hennicke, J., Parner, H., & Wanless, S. (2008) Application of habitat suitability modelling to tracking data of marine animals as a means of analyzing their feeding habitats. Ecological Modelling, 212, 504-512.
Wanless, S., Frederiksen, M., Daunt, F. Scott, B.E. & Harris, M.P. (2007) Top predators as indicators of environmental change in the North Sea: evidence from long-term studies of black-legged kittiwakes. Progress in Oceanography, 72,30-38.
Hamer, K.C., Humphreys, E.M., Garthe, S., Hennicke, J., Peters, G., Grémillet, D., Phillips, R.A., Harris, M.P. & Wanless, S. (2007) Annual variation in diets, feeding locations and foraging behaviour of gannets in the North Sea: flexibility, consistency and constraint. Marine Ecology Progress Series, 338, 295-305.
Daunt, F., Afanasyev, V., Silk, J.R.D. & Wanless, S. (2006) Extrinsic and intrinsic determinants of winter foraging and breeding phenology in a temperate seabird. Behavioural Ecology & Sociobiology, 59,381-388
Daunt, F., Wanless, S., Peters, G., Benvenuti, S., Sharples, J., Gremillet, D. & Scott, B. (2006). Impacts of oceanography on the foraging dynamics of seabirds in the North Sea. In: Top predators in marine ecosystems: their role in monitoring and management. (eds I.L. Boyd, S. Wanless & K. Camphuysen). Cambridge University Press, Cambridge, pp177-190.
Enstipp, M.R., Daunt, F., Wanless, S., Humphreys, E., Hamer, K.C., Benvenuti, S. & Gremillet, D. (2006). Foraging energetics of North Sea birds confronted with fluctuating prey availability. In: Top predators in marine ecosystems: their role in monitoring and management. (eds I.L. Boyd, S. Wanless & K. Camphuysen). Cambridge University Press, Cambridge, pp191-210.
Hamer, K.C., Lewis, S., Wanless, S., Phillips, R.A., Sherratt, T.N., Humphreys, E.M., Hennicke, J. & Garthe, S. (2006) Use of gannets to monitor prey availability in the northeast Atlantic Ocean: colony size, diet and foraging behaviour. In: Top predators in marine ecosystems: their role in monitoring and management. (eds I.L. Boyd, S. Wanless & K. Camphuysen). Cambridge University Press, Cambridge, pp236-248.
Scott, B.E., Sharples, J., Wanless, S., Ross, O., Frederiksen, M. & Daunt, F. (2006). Getting the timing right: the effect of spring bloom date on seabird breeding performance. In: Top predators in marine ecosystems: their role in monitoring and management. (eds I.L. Boyd, S. Wanless & K. Camphuysen). Cambridge University Press, Cambridge, pp46-62.
Wilson, L.J., Daunt, F. & Wanless, S. (2004) Self-feeding and chick provisioning diet differ in the Common Guillemot Uria aalge. Ardea, 92, 197-208
Lewis, S., Sherratt, T.N., Hamer, K.C., Harris, M. P. & Wanless, S. (2003) Contrasting diet quality of northern gannets Morus bassanus at two colonies. Ardea, 91, 167-175
Daunt, F., Peters, G., Scott, B., Grémillet, D. and Wanless, S. (2003) Rapid response recorders reveal interplay between marine physics and seabird behaviour. Marine Ecology Progress Series, 255, 283-288.
Wanless, S., Bacon, P. J., Harris, M. P. & Webb, A.D. (2003) Evaluating the coastal environment for marine birds. Coastal and Marine Geo-Information Systems (eds D. R. Green & S. D. King). Kluwer, The Netherlands, pp221-232
Daunt, F., Benvenuti, S., Harris M. P., Dall'Antonia L., Elston D. A. & Wanless, S. (2002) Foraging strategies of black-legged kittiwakes Rissa tridactyla at a North Sea colony: evidence for a maximum foraging range. Marine Ecology Progress Series, 245, 239-247.
Lewis, S., Benvenuti, S., Dall'Antonia, L., Griffiths, R. Money, L., Sherratt, T.N., Wanless, S. & Hamer, K.C. (2002). Sex-specific foraging behaviour in a monomorphic seabird. Proceedings Royal Society London B 269: 1687-1693.
Lewis, S., Sherratt, T.N., Hamer, K.C. & Wanless, S. (2001) Direct evidence for intraspecific competition for food in a pelagic seabird. Nature 412: 816-819.
Lewis, S., Wanless, S., Wright, P.J., Harris, M.P., Bull, J. & Elston, D.A. (2001) Diet and breeding performance of black-legged kittiwakes Rissa tridactyla at a North Sea colony. Marine Ecology Progress Series 221: 277-284.
Rindorf, A., Wanless, S., Harris, M.P. (2000) Effects of changes in sandeel availability on the reproductive output of seabirds. Marine Ecology Progress Series 202: 241-252.