Cooccurrence and food niche overlap of two common predators (red fox Vulpes vulpes and common buzzard Buteo buteo) in an agricultural landscape

Abstract

The mechanism of coexistence and interspecific relationships between 2 predatory species has been an important topic in ecology for many years. To date, researchers have focused mostly on very similar species, such as 2 mammals or 2 birds of prey, occupying the same habitat. However, the situation where a predatory mammal may live sympatrically with a common bird of prey is probably more common. A good example is the coexistence of the red fox and the common buzzard. The relationship between these species with respect to spatial distribution, the abundance of a potentially important prey species (common vole), diet, trophic niche breadth, and niche overlap was studied in western Poland during 2006-2009. The distances between fox dens and buzzard nests were significantly shorter than would be expected by chance. The abundance of common vole was higher in sites where both predators were present than in the control sites, where neither predator was recorded. The trophic niche overlap between both predators was moderate (62.1%). However, the trophic niche breadth of the common buzzard was narrower (2.733) than that of the red fox (3.875), which implies that the fox is a more generalist predator.