Vultures and Livestock: The Where, When, and Why of Visits to Farms

Abstract

Recent changes in European legislation have legalized the abandonment of carcasses around livestock farms, but our understanding of how vultures exploit these semi-predictable food sources is still very limited. For filling this gap, we determine the individual and ecological drivers influencing vulture visits to farms. We assessed the effects of individual characteristics of both birds and farms on the frequency of vultures’ visits to livestock facilities using data collected from 45 GPS-tagged Egyptian Vultures (Neophron percnopterus) and 318 farms (>94% of livestock) on Fuerteventura Island, Spain. Farms were more visited during the vultures’ breeding season. Farms located closer to highly predictable feeding places (i.e., vulture restaurants and garbage dumps) or with more available feeding resources were visited by more vultures, whereas those located close to roads and vultures’ breeding territories received fewer visits. Younger territorial birds visited a farm more frequently than older territorial ones, whereas older non-territorial individuals concentrated those visits on farms closer to their activity core areas compared with younger ones. Our findings indicate that visits to farms were determined by their spatial distribution in relation to the age-specific birds’ activity centers, the availability of carcasses, seasonality, and individual characteristics of vultures. These interacting factors should be considered in vulture conservation, avoiding very general solutions that ignore population structure.

Environmental and social correlates, and energetic consequences of fitness maximisation on different migratory behaviours in a long-lived scavenger

“…Our results showed that adult Egyptian Vultures may attract subadults and less experienced individuals by remaining in a particular place where resources are abundant and predictable (see Morant et al 2020). This pattern has also been observed in White Storks (see also Rotics et al 2016) and other sedentary populations of Egyptian Vultures where collective foraging in areas of high food predictability and availability (e.g., farms) could bene t individuals with lower social status, such as juveniles or subadults (García Alfonso et al 2020;van Overveld et al 2020b). Overall, our results evidence that migratory decisions at the population level might be in uenced by the environment (e.g., food availability), and modulated by sociality.…”

“…The Egyptian Vulture is an obligate scavenger that frequently consumes both carrion from livestock and wild ungulates (Donázar 1993). The species exhibit complex social behaviour forming large individual congregations outside the breeding season at highly preferred feeding stations (e.g., farms) and nearby temporary roosting sites (García-Alfonso et al 2020;van Overveld et al 2020a). Altogether, these traits make it an ideal study species to assess how different migratory strategies coexist.…”

Vultures feeding on the dark side: current sanitary regulations may not be enough

“…As a prior step for analytical purposes, and following the procedures of García-Alfonso et al (2020), we split the data into two “Periods”: (1) from October to February ( n = 5 months), corresponding to autumn-winter and (2) from March to September ( n = 7 months), corresponding to spring–summer. These two periods correspond roughly to non-breeding and breeding seasons, respectively.…”

Anthropogenic Drivers Leading to Population Decline and Genetic Preservation of the Eurasian Griffon Vulture (Gyps fulvus)

“…Indeed, vultures Life 2021, 11, 1038 2 of 19 reduce the rates of transmission of infectious diseases quickly consuming domestic and wild animals' carcasses. Regarding this role of vultures, the provision of supplementary safe food at artificial feeding stations (SFFS) appears to be the most important management action applied to counter sanitary problems related to intensive breeding and to the conservation of these species sensitive to poisons or drugs present in contaminated carcasses [7][8][9][10][11][12][13][14].…”