Vulture culture: dietary specialization of an obligate scavenger

Individual dietary variation has important ecological and evolutionary consequences. However, it has been overlooked in many taxa that are thought to have homogeneous diets. This is the case of vultures, considered merely as “carrion eaters”. Given their high degree of sociality, vultures are an excellent model to investigate how inter-individual transmissible behaviors drive individual dietary variation. Here, we combine GPS-tracking and accelerometers with an exhaustive fieldwork campaign to identify the individual diet of 55 griffon vultures (Gyps fulvus) from two Spanish populations that partially overlap in their foraging areas. We found that individuals from the more humanized population consumed more anthropic resources (e.g., stabled livestock or rubbish), resulting in more homogeneous diets. In contrast, individuals from the wilder population consumed more wild ungulates, increasing their dietary variability. Between sexes, we found that males consumed anthropic resources more ..., GPS-tracking and study areas
We captured 65 adult griffon vultures, 30 individuals in Southern Spain between December 2014 and January 2015 and 35 individuals in Northern Spain between December 2015 and March 2016. The Southern area is a mountainous region (500–2,107 m a.s.l.) covered by Mediterranean woodlands and pasturelands, where the main human uses are traditional farming, hunting, forestry and tourism (44). The Northern area is a flat area (28–659 m a.s.l.) surrounded by mid-sized mountains (up to 1500 m a.s.l.) and highly transformed for intensive agriculture, with traditional sheep livestock being replaced by intensive farming (45, 46). This leads to more predictable ungulate carrion sources in the Northern area compared to the Southern one (30) although trophic resources can be considered abundant in both areas. In addition to these areas, both vulture populations share a second foraging area in Southwestern Spain (Figure 1 and Figure S3) where carrion from wild and domestic u...,