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A review of spatial and temporal variation in grey and common seal diet in the United Kingdom and Ireland

Published online by Cambridge University Press:  20 January 2012

Susie L. Brown*
Affiliation:
School of Biological Sciences, Queen's University Belfast, Medical Biology Centre, 97 Lisburn Road, Belfast, BT9 7BL
Stuart Bearhop
Affiliation:
Centre for Ecology and Conservation, School of Biosciences, University of Exeter, Cornwall Campus, Penryn, Cornwall, TR10 9EZ
Chris Harrod
Affiliation:
School of Biological Sciences, Queen's University Belfast, Medical Biology Centre, 97 Lisburn Road, Belfast, BT9 7BL Facultad de Recursos del Mar, Instituto de Investigaciones Oceanológicas, Universidad Antofagasta, Avenida Angamos 601, Antofagasta, Chile
Robbie A. McDonald
Affiliation:
Environment and Sustainability Institute, University of Exeter, Cornwall Campus, Penryn, Cornwall TR10 9EZ
*
Correspondence should be addressed to: S.L. Brown, Department of Zoology, Ecology and Plant Science, Cork Enterprise Centre, University College Cork, Distillery, Fields, North Mall, Cork email: [email protected]

Abstract

Knowledge about the diet of fish-eating predators is critical when evaluating conflicts with the fishing industry. Numerous primary studies have examined the diet of grey seals Halichoerus grypus and common seals Phoca vitulina in a bid to understand the ecology of these predators. However, studies of large-scale spatial and temporal variation in seal diet are limited. Therefore this review combines the results of seal diet studies published between 1980 and 2000 to examine how seal diet varies at a range of spatial and temporal scales. Our results revealed extensive spatial variation in gadiform, perciform and flatfish consumption, likely reflecting variation in prey availability. Flatfish and gadiform consumption varied between years, reflecting changes in fish assemblages as a consequence of factors such as varying fishing pressures, climate change and natural fluctuations in populations. Perciform and gadiform consumption varied seasonally: in addition there was a significant interaction between season and seal species, indicating that grey and common seals exhibited different patterns of seasonal variation in their consumption of Perciformes and Gadiformes. Multivariate analysis of grey seal diet revealed spatial variation at a much smaller scale, with different species dominating the diet in different areas. The existence of spatial and temporal variation in seal diet emphasizes that future assessments of the impact of seal populations should not be based on past or localized estimates of diet and highlights the need for up-to-date, site specific estimates of diet composition in the context of understanding and resolving seal/fisheries conflict.

Type
Research Article
Copyright
Copyright © Marine Biological Association of the United Kingdom 2012

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References

REFERENCES

Akaike, H. (1983) Information measures and model selection. Bulletin of the International Statistical Institute 50, 277291.Google Scholar
Anonymous (1997) The physical interaction between grey seals and fishing gear. Irish Sea Fisheries Board Report to the European Commission, DG XIV study PEM/93/06.Google Scholar
Anonymous (2001) Grey seal interactions with fisheries in Irish coastal waters. Irish Sea Fisheries Board Report to the European Commission, DG XIV study 95/40.Google Scholar
Anonymous (2003) Scientific advice on matters relating to the management of seal populations. UK Special Committee on Seals.Google Scholar
Anonymous (2009) Scientific advice on matters relating to the management of seal populations. UK Special Committee on Seals.Google Scholar
Berg, I., Haug, T. and Nilseen, K.T. (2002) Harbour seal (Phoca vitulina) diet in Vesterålen, north Norway. Sarsia 87, 451461.CrossRefGoogle Scholar
Brown, E.G. and Pierce, G.J. (1997) Diet of harbour seals at Mousa, Shetland, during the third quarter of 1994. Journal of the Marine Biological Association of the United Kingdom 77, 539555.CrossRefGoogle Scholar
Brown, E.G. and Pierce, G.J. (1998) Monthly variation in the diet of harbour seals in inshore waters along the southeast Shetland (UK) coastline. Marine Ecology Progress Series 167, 275289.CrossRefGoogle Scholar
Brown, E.G., Pierce, G.J., Hislop, J.R.G. and Santos, M.B. (2001) Interannual variation in the summer diets of harbour seals Phoca vitulina at Mousa, Shetland (UK). Journal of the Marine Biological Association of the United Kingdom 81, 325337.CrossRefGoogle Scholar
Butler, J.R.A., Middlemas, S.J., Mckelvey, S.A., McMyn, I., Leyshon, B., Walker, I., Thompson, P.M., Boyd, I.L., Duck, C., Armstrong, J.D., Graham, I.M. and Baxter, J.M. (2008) The Moray Firth Seal Management Plan: an adaptive framework for balancing the conservation of seals, salmon, fisheries and wildlife tourism in the UK. Aquatic Conservation: Marine and Freshwater Ecosystems 18, 10251038.CrossRefGoogle Scholar
Clarke, K.R. and Gorley, R.N. (2006) PRIMER v6: user manual tutorial. Plymouth: PRIMER-E.Google Scholar
Clarke, K.R. and Warwick, R.M. (2001) Change in marine communities: an approach to statistical analysis and interpretation. 2nd edition.Plymouth: PRIMER-E.Google Scholar
Coltman, D.W., Bowen, W.D., Boness, D.J. and Iverson, S.J. (1997) Balancing foraging and reproduction in the male harbour seal, an aquatically mating pinniped. Animal Behaviour 54, 663678.CrossRefGoogle ScholarPubMed
Gordon, J.D.M. (1977) The fish populations in inshore waters of the west coast of Scotland: the distribution, abundance and growth of the whiting (Merlangius merlangus). Journal of Fish Biology, 10, 587596.CrossRefGoogle Scholar
Graham, C.T. and Harrod, C. (2009) Implications of climate change for the fishes of the British Isles. Journal of Fish Biology 74, 11431205.CrossRefGoogle ScholarPubMed
Hall, A.J., Watkins, J. and Hammond, P.S. (1998) Seasonal variation in the diet of harbour seals in the south-western North Sea. Marine Ecology Progress Series 170, 269281.CrossRefGoogle Scholar
Hammond, P.S., Hall, A.J. and Prime, J.H. (1994a) The diet of grey seals around Orkney and other island and mainland sites in north-eastern Scotland. Journal of Applied Ecology 31, 340350.CrossRefGoogle Scholar
Hammond, P.S., Hall, A.J. and Prime, J.H. (1994b) The diet of grey seals in the Inner and Outer Hebrides. Journal of Applied Ecology 31, 737746.CrossRefGoogle Scholar
Hansen, B.J. and Harding, K.C. (2006) On the potential impact of harbour seal predation on the cod population in the eastern North Sea. Journal of Sea Research 56, 329337.CrossRefGoogle Scholar
Härkönen, T. (1987) Seasonal and regional variation in the feeding habits of the harbour seal, Phoca vitulina, in the Skagerrak and Kattegat. Journal of the Zoological Society of London 213, 535543.CrossRefGoogle Scholar
Härkönen, T. and Heide-Jorgensen, M.P. (1991) The harbour seal Phoca vitulina as a predator in the Skagerrak. Ophelia 34, 191207.CrossRefGoogle Scholar
Harvey, J.T. (1989) Assessment of errors associated with harbour seal (Phoca vitulina) faecal sampling. Journal of Zoology 219, 101111.CrossRefGoogle Scholar
Harwood, J. and Greenwood, J.J.D. (1985) Competition between British grey seals and fisheries. In Beddington, J.R., Beverton, R.J.H. and Lavigne, D.M. (eds) Marine mammals and fisheries. London: George Allen and Unwin Ltd, pp. 153169.Google Scholar
Hauksson, E. and Bogason, V. (1997) Comparative feeding of grey (Halichoerus grypus) and common seals (Phoca vitulina) in coastal waters of Iceland, with a note on the diet of hooded (Cystophora cristata) and harp seals (Phoca groenlandica). Journal of Northwest Atlantic Fisheries Science 22, 125135.CrossRefGoogle Scholar
Hemmer-Hanson, J., Nielson, E.E., Grønkjaer, P. and Loeschcke, V. (2007) Evolutionary mechanisms shaping the genetic population of marine fishes: lesson from the European flounder (Platichthys flesus L.). Molecular Ecology 16, 31043118.CrossRefGoogle Scholar
Hofstede, R. and Rijnsdorp, A.D. (2011) Comparing demersal fish assemblages between periods of contrasting climate and fishing pressure. ICES Journal of Marine Science 68, 11891198.CrossRefGoogle Scholar
Jackson, J.B.C., Kirby, M.X., Berger, W.H., Bjorndal, K.A., Botsford, L.W., Bourque, B.J., Bradbury, R.H., Cooke, R., Erlandson, J., Estes, J.A., Hughes, T.P., Kidwell, S., Lange, C.B., Lenihan, H.S., Pandolfi, J.M., Peterson, C.H., Steneck, R.S., Tegner, M.J. and Warner, R.R. (2001) Historical overfishing and the recent collapse of coastal ecosystems. Science 293, 629638.CrossRefGoogle ScholarPubMed
Jobling, M. and Breiby, A. (1986) The use and abuse of fish otoliths in studies of feeding habits of marine piscivores. Sarsia 71, 265274.CrossRefGoogle Scholar
Kiely, O., Ligard, D., McKibben, M., Connolly, N. and Baines, M. (2000) Grey seals: status and monitoring in the Irish and Celtic Seas. Maritime Ireland/Wales INTERREG Report No.3.Google Scholar
Lambert, R.A. (2002) The grey seal in Britain: a twentieth century history of a nature conservation success. Environment and History 8, 449474.CrossRefGoogle Scholar
Leopold, M.F., Van Damme, C.J.G., Philippart, C.J.M. and Winter, C.J.N. (2001) Otoliths of North Sea fish. World Biodiversity Database CD-ROM Series.Google Scholar
Lonergan, M., Duck, C.D., Thompson, D., Mackey, B.L., Cunningham, L. and Boyd, I.L. (2007) Using sparse survey data to investigate the declining abundance of British harbour seals. Journal of Zoology 271, 261269.CrossRefGoogle Scholar
Macer, C.T. (1966) Sandeels (Ammodytidae) in the south western North Sea: their biology and fishery. MAFF Fishery Investigation London, Series 2 24, 155.Google Scholar
McConnell, B.J., Fedak, M.A., Lovell, F.P. and Hammond, P.S. (1999) Movements and foraging areas of grey seals in the North Sea. Journal of Applied Ecology 36, 573590.CrossRefGoogle Scholar
Mohn, R. and Bowen, W.D. (1996) Grey seal predation on the eastern Scotian Shelf: modelling the impact on Atlantic cod. Canadian Journal of Fisheries and Aquatic Sciences 53, 27222738.CrossRefGoogle Scholar
Myers, R.A. and Worm, B. (2003) Rapid worldwide depletion of predatory fish communities. Nature 423, 280283.CrossRefGoogle ScholarPubMed
Patterson, H.D. and Thompson, R. (1971) Recovery of inter-block information when block sizes are unequal. Biometrika 58, 545554.CrossRefGoogle Scholar
Perry, A.L., Low, P.J., Ellis, J.R. and Reynolds, J.D. (2005) Climate change and distribution shifts in marine fishes. Science 308, 19121915.CrossRefGoogle ScholarPubMed
Pierce, G.J. and Boyle, P.R. (1991) A review of methods for diet analysis in piscivorous marine mammals. Oceanography and Marine Biology: an Annual Review 29, 409486.Google Scholar
Pierce, G.J. and Santos, M.B. (2003) Diet of harbour seals (Phoca vitulina) in Mull and Skye (Inner Hebrides, western Scotland). Journal of the Marine Biological Association of the United Kingdom 83, 647650.CrossRefGoogle Scholar
Pierce, G.J., Diack, J.S.W. and Boyle, P.R. (1989) Digestive tract contents of seals in the Moray Firth area of Scotland. Journal of Fish Biology 35, 314343.CrossRefGoogle Scholar
Pierce, G.J., Miller, A., Thompson, P.M. and Hislop, J.R.G. (1991a) Prey remains in grey seal (Halichoerus grypus) faeces from the Moray Firth, north-east Scotland. Journal of the Zoological Society of London 224, 337341.CrossRefGoogle Scholar
Pierce, G.J., Thompson, P.M., Miller, A., Diack, J.S.W., Miller, D. and Boyle, P.R. (1991b) Seasonal variation in the diet of common seals (Phoca vitulina) in the Moray Firth in Scotland. Journal of the Zoological Society of London 223, 641652.CrossRefGoogle Scholar
Prime, J.H. and Hammond, P.S. (1987) Quantitative assessment of grey seal diet from faecal analysis. In Huntley, A.C., Costa, D.P., Worthy, G.A.J. and Castellini, M.A. (eds) Approaches to marine mammal energetics. Society for Marine Mammalogy, Special Publication No. 1, pp. 165181.Google Scholar
Prime, J.H. and Hammond, P.S. (1990) The diet of grey seals from the south-western North Sea assessed from analysis of hard parts found in faeces. Journal of Applied Ecology 27, 435447.CrossRefGoogle Scholar
Reay, P.J. (1970) Synopsis of biological data on north Atlantic sandeels of the genus Ammodytes. FAO Fisheries Synopsis No. 82.Google Scholar
Sharples, R.J., Arrizabalaga, B. and Hammond, P.S. (2009) Seals, sandeels and salmon: diet of harbour seals in St. Andrews Bay and the Tay Estuary, southeast Scotland. Marine Ecology Progress Series 390, 265276.CrossRefGoogle Scholar
Thompson, P.M., Pierce, G.J., Hislop, J.R.G., Miller, D. and Diack, J.S.W. (1991) Winter foraging by common seals (Phoca vitulina) in relation to food availability in the inner Moray Firth, N.E. Scotland. Journal of Animal Ecology 60, 283294.CrossRefGoogle Scholar
Thompson, P.M., Miller, D., Cooper, R. and Hammond, P.S. (1994) Changes in distribution and activity of female harbour seals during the breeding season: implications for their lactation strategy and mating patterns. Journal of Animal Ecology 63, 2430.CrossRefGoogle Scholar
Thompson, P.M., McConnell, B.J., Tollit, D.J., Mackay, A., Hunter, C. and Racey, P.A. (1996a) Comparative distribution, movements and diet of harbour and grey seals from the Moray Firth, N.E. Scotland. Journal of Applied Ecology 33, 15721584.CrossRefGoogle Scholar
Thompson, P.M., Tollit, D.J., Greenstreet, S.P.R., Mackay, A. and Corpe, H.M. (1996b) Between-year variations in the diet and behaviour of harbour seals Phoca vitulina in the Moray Firth; causes and consequences. In Greenstreet, S.P.R. and Tasker, M. (eds) Aquatic predators and their prey. Oxford: Blackwell Scientific Publications, pp. 4452.Google Scholar
Tobin, D., Wright, P.J., Gibb, F.M. and Gibb, I.M. (2010) The importance of life stage to population connectivity in whiting (Merlangius merlangus) from the northern European shelf. Marine Biology 157, 10631073.CrossRefGoogle Scholar
Tollit, D.J. and Thompson, P.M. (1996) Seasonal and between-year variations in the diet of harbour seals in the Moray Firth, Scotland. Canadian Journal of Zoology 74, 11101121.CrossRefGoogle Scholar
Tollit, D.J., Greenstreet, S.P.R. and Thompson, P.M. (1997) Prey selection by harbour seals, Phoca vitulina, in relation to variations in prey abundance. Canadian Journal of Zoology 75, 15081518.CrossRefGoogle Scholar
Tollit, D.J., Black, A.D., Thompson, P.M., Mackay, A., Corpe, H.M., Wilson, B., Van Parijs, S.M., Grellier, K. and Parlane, S. (1998) Variation in harbour seal Phoca vitulina diet and dive-depths in relation to foraging. Journal of the Zoological Society of London 244, 209222.CrossRefGoogle Scholar
Trzcinski, M.K., Mohn, R. and Bowen, W.D. (2006) Continued decline of an Atlantic cod population: how important is gray seal predation. Ecological Applications 16, 22762292.CrossRefGoogle ScholarPubMed
Wilson, S.C., Pierce, G.J., Higgins, C.M. and Armstrong, M.J. (2002) Diet of the harbour seals Phoca vitulina of Dundrum Bay, north-east Ireland. Journal of the Marine Biological Association of the United Kingdom 82, 10091018.CrossRefGoogle Scholar
Winslade, P. (1974) Behavioural studies on the lesser sandeel Ammodytes marinus (Raitt) II: The effect of light intensity on activity. Journal of Fish Biology 6, 577586.CrossRefGoogle Scholar
Wright, P.J. (1996) Is there a conflict between sandeel fisheries and seabirds? A case study at Shetland. In Greenstreet, S.P.R. and Tasker, M. (eds) Aquatic predators and their prey. Oxford: Blackwell Scientific Publications, pp. 154165.Google Scholar
Yodzis, P. (2001) Must top predators be culled for the sake of fisheries? Trends in Ecology and Evolution 16, 7884.CrossRefGoogle ScholarPubMed