1365-2656/asset/olbannerleft.gif?v=1&s=4f0919eca9042f833d018453e8f48b1e3e3123ec)
1365-2656/asset/olbannerright.gif?v=1&s=92164cf20561f2dc5785bff8431569e5b40f87aa)
You have full text access to this OnlineOpen article
Using an algorithmic model to reveal individually variable movement decisions in a wintering sea duck
Article first published online: 8 JAN 2009
DOI: 10.1111/j.1365-2656.2008.01513.x
© 2009 The Authors. Journal compilation © 2009 British Ecological Society
Additional Information
How to Cite
Oppel, S., Powell, A. N. and Dickson, D. L. (2009), Using an algorithmic model to reveal individually variable movement decisions in a wintering sea duck. Journal of Animal Ecology, 78: 524–531. doi: 10.1111/j.1365-2656.2008.01513.x
Publication History
- Issue published online: 31 MAR 2009
- Article first published online: 8 JAN 2009
- Received 28 February 2008; accepted 28 November 2008Handling Editor: Stuart Bearhop
- Abstract
- Article
- References
- Cited By
Keywords:
- algorithmic model;
- king eider;
- random forest;
- social information;
- winter movements
Summary
- 1Many migratory birds are assumed to remain fairly stationary during winter. However, recent research indicates that mid-winter movements are evident in a variety of bird species, and the factors causing individuals to move are poorly understood.
- 2We examined the winter movements of 95 individual king eiders (Somateria spectabilis, L.) tracked with satellite transmitters in the Bering Sea between 2002 and 2006 to explore whether environmental factors such as day length, location, sea ice, and habitat quality could explain the occurrence of winter movements longer than 50 km.
- 3We used a novel algorithmic random forest model to assess the importance of variables predicting whether a bird remained or departed from a wintering site.
- 4We found extremely high individual variability in winter movement decisions by king eiders, and the individual bird was the most important variable followed by location, date, and sea ice concentration.
- 5We conclude that individual strategies exist that interact with environmental conditions to form multiple movement patterns.
- 6While a minor proportion of winter movements may be forced by environmental conditions, we propose that many winter movements may be of an exploratory nature where individuals aim to acquire information about alternative wintering sites that may enhance their survival probability at some point in time when environmental fluctuation renders their preferred wintering site unsuitable.