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Jesús Bautista

Bio: Jesús Bautista is an academic researcher from Junta of Andalusia. The author has contributed to research in topics: Bonelli's eagle & Population. The author has an hindex of 9, co-authored 21 publications receiving 295 citations.

Papers
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Journal ArticleDOI
TL;DR: The role of this healthy subpopulation in an Iberian metapopulation context is discussed, and it is proposed that the potential interference of golden eagles should be taken into account when designing management strategies for Bonelli's eagles.

76 citations

Journal ArticleDOI
TL;DR: Studies on the diet of Bonelli’s eagles are reviewed in order to determine the repercussions of the reduction in the density of its main prey, the rabbit, caused by outbreaks of rabbit haemorrhagic disease since 1988.
Abstract: Aim To explore the influence of an emerging infectious disease (EID) affecting a prey species on the spatial patterns and temporal shifts in the diet of a predator over a large geographical scale We reviewed studies on the diet of Bonelli’s eagles (Hieraaetus fasciatus) in order to determine the repercussions of the reduction in the density of its main prey, the rabbit (Oryctolagus cuniculus), caused by outbreaks of rabbit haemorrhagic disease (RHD) since 1988 Location Western continental Europe Methods We compiled published and unpublished information on the diet of breeding Bonelli’s eagles from Portugal, Spain and France for a 39-year study period (1968–2006) Nonparametric tests were used in order to analyse temporal shifts in diet composition and trophic diversity (H′) between the periods of ‘high’ (before outbreak of RHD) and ‘low’ rabbit density (after outbreak of RHD) A combination of hierarchical agglomerative clustering and non-metric multidimensional scaling (NMDS) analyses were used to test for the existence of geographical patterns in the diet of Bonelli’s eagles in each period Results The diet of the Bonelli’s eagle consisted of rabbit (285%), pigeons (240%), partridges (153%), ‘other birds’ (116%), ‘other mammals’ (71%), corvids (70%), and herptiles (64%) However, RHD had large consequences for its feeding ecology: the consumption of rabbits decreased by one-third after the outbreak of RHD Conversely, trophic diversity (H′) increased after outbreak of RHD At the same time, the analyses showed clear geographical patterns in the diet of the Bonelli’s eagle before, but not after, RHD outbreak Main conclusions Geographical patterns in the diet of the Bonelli’s eagle in western Europe seem to be driven mainly by spatio-temporal variation in the abundance of rabbits and, to a lesser extent, by the local (territorial) environmental features conditioning the presence and density of alternative prey species We show that an EID can disrupt predator–prey relationships at large spatial and temporal scales through a severe decline in the population of the main prey species Hence we argue that strict guidelines should be drawn up to prevent human-aided dissemination of ‘pathogen pollution’, which can threaten wildlife not only at the population and species level but also at the community and ecosystem scale

71 citations

Journal ArticleDOI
TL;DR: For the first time for a raptor species, a positive relationship between the frequency of occurrence of lead shots in pellets and lead concentration in eagles' feathers has been documented and shows that some game modalities pose a potential threat to endangered raptors.

36 citations

Journal Article
01 Jan 2007-Ardeola
TL;DR: In this paper, the authors present a study of the dieta of aguilas-azor perdiceras Hieraaetus fasciatus territoriales during the periodo no reproductor in the peninsula Iberica.
Abstract: Presentamos los primeros datos sobre la dieta de las aguilas-azor perdiceras Hieraaetus fasciatus territoriales durante el periodo no reproductor en la peninsula Iberica. El estudio, realizado en dos areas, una del sur (Granada) y otra del noreste (Cataluna) de Espana, mostro que existen diferencias alimenticias tanto geograficas como estacionales. El aguila parece comportarse como un especialista facultativo sobre el conejo, de manera que prefiere esta presa cuando es relativamente abundante pero desvia su atencion hacia presas alternativas cuando el conejo es demasiado escaso. El consumo de perdices rojas parece estar condicionado por la abundancia de conejo y el conspicuo comportamiento de los machos de perdiz durante el celo. En los lugares y epocas donde los conejos y, en menor medida, las perdices estan menos disponibles para las aguilas, presas como las palomas y otras aves adquieren especial relevancia. Las preferencias alimenticias y las restricciones impuestas por la disponibilidad de las presas incrementan la vulnerabilidad de las aguilas-azor perdiceras hacia amenazas de origen antropico, circunstancia que se ve acentuada en epoca no reproductora.

17 citations

Journal ArticleDOI
TL;DR: Capsule Birds at dispersal areas consumed more rabbits than adult territorial eagles in areas with high concentrations of eagles.
Abstract: Capsule Birds at dispersal areas consumed more rabbits than adult territorial eagles.

16 citations


Cited by
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30 Apr 1984
TL;DR: A review of the literature on optimal foraging can be found in this article, with a focus on the theoretical developments and the data that permit tests of the predictions, and the authors conclude that the simple models so far formulated are supported by available data and that they are optimistic about the value both now and in the future.
Abstract: Beginning with Emlen (1966) and MacArthur and Pianka (1966) and extending through the last ten years, several authors have sought to predict the foraging behavior of animals by means of mathematical models. These models are very similar,in that they all assume that the fitness of a foraging animal is a function of the efficiency of foraging measured in terms of some "currency" (Schoener, 1971) -usually energy- and that natural selection has resulted in animals that forage so as to maximize this fitness. As a result of these similarities, the models have become known as "optimal foraging models"; and the theory that embodies them, "optimal foraging theory." The situations to which optimal foraging theory has been applied, with the exception of a few recent studies, can be divided into the following four categories: (1) choice by an animal of which food types to eat (i.e., optimal diet); (2) choice of which patch type to feed in (i.e., optimal patch choice); (3) optimal allocation of time to different patches; and (4) optimal patterns and speed of movements. In this review we discuss each of these categories separately, dealing with both the theoretical developments and the data that permit tests of the predictions. The review is selective in the sense that we emphasize studies that either develop testable predictions or that attempt to test predictions in a precise quantitative manner. We also discuss what we see to be some of the future developments in the area of optimal foraging theory and how this theory can be related to other areas of biology. Our general conclusion is that the simple models so far formulated are supported are supported reasonably well by available data and that we are optimistic about the value both now and in the future of optimal foraging theory. We argue, however, that these simple models will requre much modification, espicially to deal with situations that either cannot easily be put into one or another of the above four categories or entail currencies more complicated that just energy.

2,709 citations

Journal Article
TL;DR: In this paper, a test based on two conserved CHD (chromo-helicase-DNA-binding) genes that are located on the avian sex chromosomes of all birds, with the possible exception of the ratites (ostriches, etc.).

2,554 citations

Journal ArticleDOI
01 Jul 2006-The Auk
TL;DR: In this paper, the authors express the opinions of the individual evaluators regarding the strengths, weaknesses, and value of the books they review, as such the appraisals are subjective assessments and do not necessarily reflect the opinion of the editors or any official policy of the American Ornithologists' Union.
Abstract: Abstract The following critiques express the opinions of the individual evaluators regarding the strengths, weaknesses, and value of the books they review. As such, the appraisals are subjective assessments and do not necessarily reflect the opinions of the editors or any official policy of the American Ornithologists' Union.

661 citations