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Vultures are recognized as the scroungers of the natural world, owing to their ecological role as obligate scavengers. While it is well known that vultures use intraspecific social information as they forage, the possibility of inter-guild social information transfer and the resulting multi-species social dilemmas has not been explored. Here, we use data on arrival times at carcasses to show th...

JOSÉ A. MARTÍNEZ, 1 JOSÉ F. CALVO, 2 * JOSÉ E. MARTÍNEZ, 2 IÑIGO ZUBEROGOITIA, 3 JABI ZABALA 3 & STEPHEN M. REDPATH 4 1 C/Juan de la Cierva 43, El Campello, E-03560 Alicante, Spain 2 Departamento de Ecología e Hidrología, Universidad de Murcia, E-30100 Murcia, Spain 3 Estudios Medioambientales Icarus s.l., Oficina Técnica, Apd. 106, E-48940 Leioa, Bizkaia, Spain 4 Centre for Ecology and Hydrolo...

—From 1980 to 1998, Washington’s Bald Eagle (Haliaeetus leucocephalus) population increased at an annual rate of 10%. Over the same time period, foraging activity of Bald Eagles at marine bird breeding colonies also increased. From 1993 to 2008, we observed foraging-related behavior of Bald Eagles on Violet Point, Protection Island. This island hosts more than 70% of the breeding seabirds in Wa...

BACKGROUND An impressive number of studies have investigated bird vocal displays, and many of them have tried to explain the widespread phenomenon of the so-called dawn and dusk chorus, the sunrise and sunset peaks in bird song output. As many as twelve non-exclusive hypotheses have been proposed to explain why twilight peaks in vocal display might be advantageous; but, even after more than two...

In the Tapajos-Xingu interfluve, one of the largest birds of prey, the Harpy Eagle, is under intense anthropogenic pressure due to historical and recent reductions in forest cover. We studied prey availability and use by Harpy Eagle on six breeding territories on the low- and mid-Xingu River, between 2013 and 2015. We evaluated food resource availability using the environmental-surveys database...

Electrocution by power lines is one of the main causes of non-natural mortality in birds of prey. In an area in central Spain, we surveyed 6304 pylons from 333 power lines to determine electrocution rates, environmental and design factors that may influence electrocution and the efficacy of mitigation measures used to minimise electrocution cases. A total of 952 electrocuted raptors, representi...

Information concerning parasites of the bald eagle (Haliaeetus leucocephalus) in North America is relatively sparse. Since the bald eagle in parts of the United States is an endangered species, collection of eagles for parasito!ogical study is difficult. There have been several singular reports of parasites found in oron bald eagles in the literature. However, Kocan and Locke (1974, J. Wild!. I...

BACKGROUND Predation may potentially lead to negative effects on both prey (directly via predators) and predators (indirectly via human persecution). Predation pressure studies are, therefore, of major interest in the fields of theoretical knowledge and conservation of prey or predator species, with wide ramifications and profound implications in human-wildlife conflicts. However, detailed work...