Declining survival rates in a reintroduced population of the Mauritius kestrel: evidence for non-linear density dependence and environmental stochasticity
Article first published online: 10 NOV 2003
Journal of Animal Ecology
Volume 72, Issue 6, pages 917–926, November 2003
How to Cite
Nicoll, M. A. C., Jones, Carl. G. and Norris, K. (2003), Declining survival rates in a reintroduced population of the Mauritius kestrel: evidence for non-linear density dependence and environmental stochasticity. Journal of Animal Ecology, 72: 917–926. doi: 10.1046/j.1365-2656.2003.00768.x
- Issue published online: 10 NOV 2003
- Article first published online: 10 NOV 2003
- Received 10 February 2003; revision received 10 May 2003
- population demography;
- program MARK;
- threatened species
- 1We studied a reintroduced population of the formerly critically endangered Mauritius kestrel Falco punctatus Temmink from its inception in 1987 until 2002, by which time the population had attained carrying capacity for the study area. Post-1994 the population received minimal management other than the provision of nestboxes.
- 2We analysed data collected on survival (1987–2002) using program MARK to explore the influence of density-dependent and independent processes on survival over the course of the population's development.
- 3We found evidence for non-linear, threshold density dependence in juvenile survival rates. Juvenile survival was also strongly influenced by climate, with the temporal distribution of rainfall during the cyclone season being the most influential climatic variable. Adult survival remained constant throughout.
- 4Our most parsimonious capture–mark–recapture statistical model, which was constrained by density and climate, explained 75·4% of the temporal variation exhibited in juvenile survival rates over the course of the population's development.
- 5This study is an example of how data collected as part of a threatened species recovery programme can be used to explore the role and functional form of natural population regulatory processes. With the improvements in conservation management techniques and the resulting success stories, formerly threatened species offer unique opportunities to further our understanding of the fundamental principles of population ecology.