Studying Movement of Avian Scavengers to Understand Carrion Ecology

Abstract

Scavenging is a key process in the ecosystems. Studying foraging movements of obligate scavengers such as vultures can contribute to a better understanding of the scavenging-related patterns and processes. Here we review methods that can be used to track foraging vultures in the field. Yet, in order to track, vultures need to be trapped and tagged in manner that would ensure their health and normal survival and behavior. GPS telemetry is currently the best tool to track vultures for foraging studies. In a review of recent studies, we highlight the predominance of studies of species from Europe, North America and Southern Africa, and we deplore the lack of knowledge of species from the Tropics. Home ranges vary tremendously between sites, season and species (from a few km2 to >300,000 km2) but also depending on the analysis method used. Daily distances travelled are more repeatable between species, with values ranging between 30 and 40 km. Yet the way that carrion distribution can affect scavenger distribution and foraging behavior is still poorly understood.