Abstract
Buffer effects occur when sites vary in quality and fluctuations in population size are mirrored by large changes in animal numbers in poor-quality sites but only small changes in good-quality sites. Hence, the poor sites ‘buffer’ the good sites1,2, a mechanism that can potentially drive population regulation if there are demographic costs of inhabiting poor sites. Here we show that for a migratory bird this process can apply on a country-wide scale with consequences for both survival and timing of arrival on the breeding grounds (an indicator of reproductive success3,4). The Icelandic population of the black-tailed godwit, Limosa limosa islandica, wintering in Britain has increased fourfold since the 1970s (ref. 5) but rates of change within individual estuaries have varied from zero to sixfold increases. In accordance with the buffer effect, rates of increase are greater on estuaries with low initial numbers, and godwits on these sites have lower prey-intake rates, lower survival rates and arrive later in Iceland than godwits on sites with stable populations. The buffer effect can therefore be a major process influencing large-scale population regulation of migratory species.
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References
Kluyver, H. N. & Tinbergen, L. Territory and the regulation of density in titmice. Arch. Néerl. Zool. 10, 265–289 (1953).
Brown, J. L. The buffer effect and productivity in tit populations. Am. Nat. 103, 347–354 (1969).
Kokko, H. Competition for early arrival in migratory birds. J. Anim. Ecol. 68, 940–950 (1999).
Møller, A. P. Phenotype-dependent arrival time and its consequences in a migratory bird. Behav. Ecol. Sociobiol. 35, 115–122 (1994).
Pollitt, M. S. et al. The Wetland Bird Survey 1998–99: Wildfowl and Wader Counts (BTO, WWT, RSPB & JNCC, Slimbridge, 2000).
Krebs, J. R. Regulation of numbers in the Great Tit (Aves: Passeriformes). J. Zool. 162, 317–333 (1970).
Ferrer, M. & Donazar, J. A. Density-dependent fecundity by habitat heterogeneity in an increasing population of Spanish Imperial Eagles. Ecology 77, 69–74 (1996).
Fraser, D. & Sise, T. Observations on stream minnows in a patchy environment: a test of theory of habitat selection. Ecology 61, 790–797 (1980).
Halama, K. J. & Dueser, R. D. Of mice and habitats: tests for density-dependent habitat selection. Oikos 69, 107–114 (1994).
Fretwell, S. D. & Lucas, H. J. Jr. On territorial behaviour and other factors influencing habitat distribution in birds. Acta Biotheor. 19, 16–36 (1970).
Underhill, L. G. & Prys-Jones, R. Index numbers for waterbird populations. I. Review and methodology. J. Appl. Ecol. 31, 463–480 (1994).
Sutherland, W. J. From Individual Behaviour to Population Ecology (Oxford Univ. Press, Oxford, 1996).
Moser, M. E. Limits to the numbers of grey plovers Pluvialis squatarola wintering on British estuaries: an analysis of long-term population trends. J. Appl. Ecol. 25, 473–485 (1988).
Goss-Custard, J. D. Competition for food and interference among waders. Ardea 68, 31–52 (1980).
Gill, J. A., Sutherland, W. J. & Norris, K. Depletion models can predict shorebird distribution at different spatial scales. Proc. R. Soc. Lond. B 268, 369–376 (2001).
Kay, D. G. & Knights, R. D. The macro-invertebrate fauna of the intertidal soft sediments of south east England. J. Mar. Biol. Assoc. UK 55, 811–832 (1975).
White, G. C. & Burnham, K. P. Program MARK: survival estimation from populations of marked animals. Bird Study 46, S120–S139 (2000).
Currie, D., Thompson, D. B. A. & Burke, T. Patterns of territory settlement and consequences for breeding success in the Northern Wheatear Oenanthe oenanthe. Ibis 142, 389–398 (2000).
Sandercock, B. K., Lank, D. B. & Cooke, F. Seasonal declines in the fecundity of arctic-breeding sandpipers: different tactics in two species with an invariant clutch size. J. Avian Biol. 30, 460–468 (1999).
Lepage, D., Gauthier, G. & Menu, S. Reproductive consequences of egg-laying decisions in snow geese. J. Anim. Ecol. 69, 414–427 (2000).
Acknowledgements
We are grateful for the financial and technical support of NERC; the TMR programme of the EC through Sandgerdi Marine Institute, Iceland; and A. Gardarsson and the Icelandic Institute of Natural History. We are grateful to L. Norton, J. Smart, D. McNeill, R. Croger, G. Appleton and T. Turner for assistance in the field, and to I. Côté, J. Reynolds and A. Watkinson for comments on the manuscript. Survival data were generated from Farlington Ringing Group and Wash Wader Ringing Group colour-ringing schemes. The FRG scheme is partly funded by the Farlington Ringing Group, Hampshire Ornithological Society and Hampshire County Council. Wetland Bird Survey data were provided by the British Trust for Ornithology.
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Gill, J., Norris, K., Potts, P. et al. The buffer effect and large-scale population regulation in migratory birds. Nature 412, 436–438 (2001). https://doi.org/10.1038/35086568
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DOI: https://doi.org/10.1038/35086568
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