Habitat use throughout migration: linking individual consistency, prior breeding success and future breeding potential
Article first published online: 24 JAN 2012
© 2012 The Authors. Journal of Animal Ecology © 2012 British Ecological Society
Journal of Animal Ecology
Volume 81, Issue 3, pages 657–666, May 2012
How to Cite
Hoye, B. J., Hahn, S., Nolet, B. A. and Klaassen, M. (2012), Habitat use throughout migration: linking individual consistency, prior breeding success and future breeding potential. Journal of Animal Ecology, 81: 657–666. doi: 10.1111/j.1365-2656.2011.01948.x
- Issue published online: 10 APR 2012
- Article first published online: 24 JAN 2012
- Received 22 March 2011; accepted 12 December 2011 Handling Editor: Stuart Bearhop
- dietary specialization;
- lifetime reproductive success;
- migratory flyway;
- resource use;
- seasonal interaction
1. Habitat use can influence individual performance in a wide range of animals, either immediately or through carry-over effects in subsequent seasons. Given that many animal species also show consistent individual differences in reproductive success, it seems plausible that individuals may have consistent patterns of habitat use representing individual specializations, with concomitant fitness consequences.
2. Stable-carbon isotope ratios from a range of tissues were used to discern individual consistency in habitat use along a terrestrial–aquatic gradient in a long-distance migrant, the Bewick’s swan (Cygnus columbianus bewickii). These individual specialisations represented <15% of the isotopic breadth of the population for the majority of individuals and were seen to persist throughout autumn migration and overwintering until aquatic habitats were no longer available.
3. Individual foraging specialisations were then used to demonstrate two consecutive carry-over effects associated with macroscale habitat segregation: consequences of breeding season processes for autumn habitat use; and consequences of autumn habitat use for future reproductive success. Adults that were successful breeders in the year of capture used terrestrial habitats significantly more than adults that were not successful, revealing a substantial cost of reproduction and extended parental care. Use of aquatic habitats during autumn was, however, associated with increased body condition prior to spring migration; and increased subsequent breeding success in adults that had been unsuccessful the year before. Yet adults that were successful breeders in the year of capture remained the most likely to be successful the following year, despite their use of terrestrial habitats.
4. Our results uniquely demonstrate not only individual foraging specializations throughout the migration period, but also that processes during breeding and autumn migration, mediated by individual consistency, may play a fundamental role in the population dynamics of long-distance migrants. These findings, therefore, highlight the importance of long-term consistency to our understanding of habitat function, interindividual differences in fitness, population dynamics and the evolution of migratory strategies.