Changes in intrapopulation resource use patterns of an endangered raptor in response to a disease-mediated crash in prey abundance
Article first published online: 7 JUN 2012
© 2012 The Authors. Journal of Animal Ecology © 2012 British Ecological Society
Journal of Animal Ecology
Volume 81, Issue 6, pages 1154–1160, November 2012
How to Cite
Moleón, M., Sebastián-González, E., Sánchez-Zapata, J. A., Real, J., Pires, M. M., Gil-Sánchez, J. M., Bautista, J., Palma, L., Bayle, P., Guimarães, P. R. and Beja, P. (2012), Changes in intrapopulation resource use patterns of an endangered raptor in response to a disease-mediated crash in prey abundance. Journal of Animal Ecology, 81: 1154–1160. doi: 10.1111/j.1365-2656.2012.02006.x
- Issue published online: 29 OCT 2012
- Article first published online: 7 JUN 2012
- Received 15 January 2012; accepted 29 April 2012 Handling Editor: Daniel Tompkins
- Aquila fasciata ;
- diet variation;
- emerging infectious disease;
- foraging theory;
- Oryctolagus cuniculus ;
- rabbit haemorrhagic disease;
- western Europe
1. A long-standing question in ecology is how natural populations respond to a changing environment. Emergent optimal foraging theory-based models for individual variation go beyond the population level and predict how its individuals would respond to disturbances that produce changes in resource availability.
2. Evaluating variations in resource use patterns at the intrapopulation level in wild populations under changing environmental conditions would allow to further advance in the research on foraging ecology and evolution by gaining a better idea of the underlying mechanisms explaining trophic diversity.
3. In this study, we use a large spatio-temporal scale data set (western continental Europe, 1968–2006) on the diet of Bonelli’s Eagle Aquila fasciata breeding pairs to analyse the predator trophic responses at the intrapopulation level to a prey population crash. In particular, we borrow metrics from studies on network structure and intrapopulation variation to understand how an emerging infectious disease [the rabbit haemorrhagic disease (RHD)] that caused the density of the eagle’s primary prey (rabbit Oryctolagus cuniculus) to dramatically drop across Europe impacted on resource use patterns of this endangered raptor.
4. Following the major RHD outbreak, substantial changes in Bonelli’s Eagle’s diet diversity and organisation patterns at the intrapopulation level took place. Dietary variation among breeding pairs was larger after than before the outbreak. Before RHD, there were no clusters of pairs with similar diets, but significant clustering emerged after RHD. Moreover, diets at the pair level presented a nested pattern before RHD, but not after.
5. Here, we reveal how intrapopulation patterns of resource use can quantitatively and qualitatively vary, given drastic changes in resource availability.
6. For the first time, we show that a pathogen of a prey species can indirectly impact the intrapopulation patterns of resource use of an endangered predator.