Supplemental feeding regimes for Egyptian vultures in the Negev Desert, Israel

Supplemental feeding is increasingly used to support vulture populations threatened by declining food resources. As the practice moves from a stopgap procedure to a management technique, information is needed on the effects of variations in feeding regime on vulture behavior. We provided food to Egyptian vultures (Neophron percnopterus) in the Negev Desert, Israel, under 2 regimes. A regular feeding station (RFS) was stocked daily with 5-10 kg of chicken carcasses, and an irregular feeding station (IFS) was stocked approximately twice monthly with 20-350 kg of livestock carcasses. At the RFS, numbers peaked at 20-30 birds; flock size at the IFS peaked at 30-40 birds. Adults feeding on chickens could dominate individual carcasses and fed in higher proportions than younger birds. Large carcasses and scattered scraps at the IFS could not be defended by individuals, and adults did not feed preferentially. Small, daily food deliveries favored adults and resulted in higher proportions of flocks feeding. Large, infrequent deliveries did not favor any age class; however, infrequent food deliveries may not provide sufficiently regular food for adults feeding young. Smaller competing scavengers at the RFS did not exclude Egyptian vultures from food. At the IFS, large mammals briefly excluded vultures but often improved access to food by tearing open carcasses. Eurasian griffons (Gyps fulvus) at the IFS excluded Egyptian vultures and consumed most of the available food. Eurasian griffons did not feed on chicken carcasses; hence, small carcasses can be used to feed small vulture species preferentially when species that specialize on large carcasses are also present.