Diet composition and foraging success in generalist predators: Are specialist individuals better foragers?
Factors affecting individual diet specialization in generalist populations and the relationship between diet and foraging successremain poorly studied, particularly in terrestrial wide-ranging predators. We studied whether individual variations in diet inMontagu’s harrier males (determined through a combination of direct foraging observations and pellet analysis) were associatedwith patterns of foraging habitat selection and foraging success of 12 radiotracked males during the breeding period. We foundimportant differences in diet composition and breadth between individuals. Diet diversity was negatively related to huntingsuccess: the most efficient individuals in terms of hunting success had the most specialized diet. This study also suggests animportant role of individual foraging habitat selection in explaining individual diet, as the proportion of different prey typesin the diet was associated with habitat composition within the home range, with higher proportion of those habitats that heldhigher abundances of their more frequent prey. This study thus provides evidence of individual diet specialization having aknock-on effect on foraging efficiency in a wide-ranging raptor and highlights the role of individual behaviour as a driving forceof intra-population niche variation.
Per més informació:
- Terraube, J., Guixé, D. & Arroyo, B (2014). Diet composition and foraging success in generalist predators: Are specialist individualsbetter foragers? Basic and Applied Ecology (2014), http://dx.doi.org/10.1016/j.baae.2014.08.008