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Moreno-Opo R.,Complutense University of Madrid | Trujillano A.,Bearded Vulture Study and Protection Group | Arredondo T.,FOMECAM S. L. Aragon 43 | Gonzalez L.M.,Deputy General Directorate on Nature | And 2 more authors.
Biological Conservation | Year: 2015

Supplementary feeding is one of the most common techniques used to alleviate threats to scavengers species related to the quality and availability of food resources. Because supplementary feeding may have undesired effects, the management of supplementary sites should be optimized from an ecological and conservation perspective. We installed high-resolution videocameras at six Spanish feeding stations recording more that 7500 h of observations at 105 feeding events. We analyzed food preferences in the four European vulture species (Eurasian griffon vulture Gyps fulvus, Egyptian vulture Neophron percnopterus, bearded vulture Gypaetus barbatus and cinereous vulture Aegypius monachus) as they relate to the characteristics of the food remains and carcasses provided at feeding sites. Our results suggest that carrion features (format, scattering, prey species, biomass and items) influence differential selection between species and age-classes. At a species level, large inputs of unscattered carrion increased the abundance of actively feeding griffon vultures. The ratio of the abundance of bearded vultures, Egyptian vultures and cinereous vultures with respect to griffon vultures was favored when less biomass was supplied and when the food provided was not presented as whole carcasses. Thus, using medium-size ungulates (i.e. sheep and goats) presented as small, abundant and scattered pieces favors the consumption of the resource by the most endangered species. Our findings can be used to optimize the supplementary provisioning of vultures in cases where this conservation tool is considered essential for managing targeted species or population groups. © 2014 Elsevier Ltd.


Cardona M.,University of Lleida | Colomer M.A.,University of Lleida | Margalida A.,Bearded Vulture Study and Protection Group | Perez-Hurtado I.,University of Seville | And 2 more authors.
Lecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics) | Year: 2010

In [1], we presented a P system in order to study the evolution of the bearded vulture in the Pyrenees (NE Spain). Here, we present a new model that overcomes some limitations of the previous work incorporating other scavenger species and additional prey species that provide food for the scavenger intraguild and interact with the Bearded Vulture in the ecosystem. After the validation, the new model can be a useful tool for the study of the evolution and management of the ecosystem. P systems provide a high level computational modelling framework which integrates the structural and dynamical aspects of ecosystems in a compressive and relevant way. The inherent randomness and uncertainty in ecosystems is captured by using probabilistic strategies. © 2010 Springer-Verlag.


Colomer M.A.,University of Lleida | Margalida A.,Bearded Vulture Study and Protection Group | Sanuy D.,University of Lleida | Perez-Jimenez M.J.,University of Seville
Ecological Modelling | Year: 2011

The models used for ecosystems modeling are generally based on differential equations. However, in recent years new computational models based on biological processes, or bioinspired models, have arisen, among which are P systems. These are inspired by the functions of cells and present important advantages with respect to traditional models, such as a high computational efficiency, modularity and their ability to work in parallel. They are simple, individual-based models that use biological parameters that can be obtained experimentally. In this work, we present the framework for a model based on P systems applied to the study of an ecosystem in which three avian scavengers (predators) interact with 10 wild and domestic ungulates (preys). The computation time for 100 repetitions, corresponding to 14 simulation years each, with an initial population composed of 385,422 individuals, was 30 min. Our results suggest that the model presented, based on P systems, correctly simulates the population dynamics in the period of time analyzed. We discuss the usefulness of this tool in simulating complex ecosystems dynamics to aid managers, conservationists and policy-makers in making appropriate decisions for the improvement of management and conservation programs. © 2010 Elsevier B.V.


Hernandez M.,Laboratorio Forense Of Vida Silvestre | Margalida A.,Bearded Vulture Study and Protection Group
Journal of Wildlife Diseases | Year: 2010

Normal hematologic and blood chemistry values for clinical use and age-related changes are reported as reference values for the endangered Bearded Vulture (Gypaetus barbatus). Blood samples were obtained from 21 nestlings and 26 free-living subadults and adults. No significant differences were found between subadults and adults or between sexes for any of the studied parameters. Reference ranges have been established for Bearded Vulture nestlings (less than 3 mo of age) and for free-living Bearded Vultures, with subadult and adult data combined without affecting clinical interpretation, Some reference values for the parameters reported in this study are similar to those previously described for vultures and other raptor species, although creatine Phosphokinase and lactate dehydrogenase activities were higher than those reported for birds ofprey. Significant age-related differences were identified in urea, uric acid, triglycerides, total serum protein, inorganic phosphorus, and magnesium concentrations, as well as aspartate aminotransferase, creatine Phosphokinase, lactate dehydrogenase, alkaline phosphatase, amylase, and lipase activities (P<0.05). Additionally, significant age-related differences were noted in red and white blood cell counts, packed cell volume, hemoglobin concentration, mean corpuscular volume, mean corpuscular hemoglobin concentration, fibrinogen level, and heterophils, lymphocytes, and eosinophils (P<0.005). The results obtained from this study provide reference ranges that will be useful for evaluating the pathologic conditions and general health of Bearded Vulture populations and reveal the existence of important agerelated differences in the species. © Wildlife Disease Association 2010.


Moreno-Opo R.,CBD Habitat Foundation | Fernandez-Olalla M.,Technical University of Madrid | Margalida A.,Bearded Vulture Study and Protection Group | Margalida A.,University of Bern | And 2 more authors.
PLoS ONE | Year: 2012

The application of scientific-based conservation measures requires that sampling methodologies in studies modelling similar ecological aspects produce comparable results making easier their interpretation. We aimed to show how the choice of different methodological and ecological approaches can affect conclusions in nest-site selection studies along different Palearctic meta-populations of an indicator species. First, a multivariate analysis of the variables affecting nest-site selection in a breeding colony of cinereous vulture (Aegypius monachus) in central Spain was performed. Then, a meta-analysis was applied to establish how methodological and habitat-type factors determine differences and similarities in the results obtained by previous studies that have modelled the forest breeding habitat of the species. Our results revealed patterns in nesting-habitat modelling by the cinereous vulture throughout its whole range: steep and south-facing slopes, great cover of large trees and distance to human activities were generally selected. The ratio and situation of the studied plots (nests/random), the use of plots vs. polygons as sampling units and the number of years of data set determined the variability explained by the model. Moreover, a greater size of the breeding colony implied that ecological and geomorphological variables at landscape level were more influential. Additionally, human activities affected in greater proportion to colonies situated in Mediterranean forests. For the first time, a meta-analysis regarding the factors determining nest-site selection heterogeneity for a single species at broad scale was achieved. It is essential to homogenize and coordinate experimental design in modelling the selection of species' ecological requirements in order to avoid that differences in results among studies would be due to methodological heterogeneity. This would optimize best conservation and management practices for habitats and species in a global context. © 2012 Moreno-Opo et al.


Margalida A.,Bearded Vulture Study and Protection Group | Margalida A.,University of Bern | Benitez J.R.,Linea de Geodiversidad y Biodiversidad | Sanchez-Zapata J.A.,University Miguel Hernández | And 3 more authors.
Ibis | Year: 2012

Between 2000 and 2009 we studied the diet and breeding success of Egyptian Vultures Neophron percnopterus in southern Spain. Wild species accounted for 74.9% of prey items (n=1071) with a predominance of mammals (62.3%), followed by birds (20.8%) and reptiles (13.1%). Spatially, the diet was highly varied and not restricted to carcasses of livestock; wild Rabbits Oryctolagus cuniculus accounted for 54% of the overall remains. The spatial variability may reflect regional and local disparity in the availability of main prey. The temporal relationship between variation in trophic diversity and Vulture nesting productivity (both values showing a long-term decrease) might suggest a causal link between variation in diet and reproductive output. We hypothesize that high turnover rates could explain productivity variation as a consequence of the recruitment of less experienced individuals to the breeding population. This could in turn generate covariation between diet and reproductive output. © 2011 The Authors. Ibis © 2011 British Ornithologists' Union.


Margalida A.,Bearded Vulture Study and Protection Group | Donazar J.A.,CSIC - Doñana Biological Station | Carrete M.,CSIC - Doñana Biological Station | Carrete M.,Pablo De Olavide University | Sanchez-Zapata J.A.,University Miguel Hernández
Journal of Applied Ecology | Year: 2010

Between 1996 and 2000 the appearance of bovine spongiform encephalopathy swiftly became one of the most serious public health and political crises concerning food safety ever experienced in the European Union (EU). Subsequent sanitary regulations led to profound changes in the management of livestock carcasses (i.e. the industrial destruction of around 80% of all animal carcasses), thereby threatening the last remaining healthy scavenger populations of the Old World and thus contradicting the long-term environmental policies of the EU.2. Several warning signs such as a decrease in breeding success, an apparent increase in mortality in young age classes of vultures and an increase in the number of cases of vultures attacking and killing cattle, as well as a halt in population growth, suggest that the decrease in the availability of food resources has had harmful effects on vulture populations.3. Between 2002 and 2005, a number of dispositions to the EU regulations (2003/322/CE 2005/830/CE) enabled conservation managers to adopt rapid solutions (i.e. the creation of vulture restaurants) aimed at satisfying the food requirements of vultures. However, these conservation measures may seriously modify habitat quality and have indirect detrimental effects on avian scavenger populations and communities.4. Synthesis and applications. Conservation managers and policy-makers need to balance the demands of public health protection and the long-term conservation of biodiversity. The regulations concerning carrion provisioning need to be more flexible and there needs to be greater compatibility between sanitary and environmental policies. We advocate policies that authorize the abandonment of livestock carcasses and favours populations of wild herbivores to help to maintain populations of avian scavengers. Conservation strategies should be incorporated into new European Commission regulations, which should be effective in 2011. © 2010 The Authors. Journal compilation © 2010 British Ecological Society.


Margalida A.,Bearded Vulture Study and Protection Group
European Journal of Wildlife Research | Year: 2010

One of the most widespread tools in the conservation of scavenger species is the provision of supplementary food. However, scientific studies on its effectiveness have been rarely conducted. Here, we present the first results of an experimental specific supplementary feeding programme applied from hatching to 45-60 days, aimed at increasing the breeding success of an obligate brood reducer, the threatened bearded vulture Gypaetus barbatus. We tested its effectiveness in the Spanish Pyrenees, the locale of the most important population of this species in the European Union, in which a regressive trend in breeding parameters has been observed in recent years. We compared the breeding success in nests with supplementary food to non-supplemented control nests. Supplementary food did not significantly increase global breeding success (supplemented nests, 0.793 ± 0.193 chicks per pair with eggs hatched vs non-supplemented nests, 0. 771 ± 0.185) or the individual breeding performance of the territories (supplemented period, 0.712 ± 0.307 vs non-supplemented period, 0.642 ± 0.311). The similar values obtained suggest that the specific supplementary feeding programme applied during the chick-rearing period is apparently ineffective at increasing breeding success. The results suggest that, at least in the study area, factors that provoke breeding failure after hatching continue to operate independently of the supplementary feeding programme. Although more research on this subject is required, these preliminary conclusions should be taken into account by managers in order to optimise the investment of economic resources and to better prioritise the future establishment of alternative conservation actions. © 2010 Springer-Verlag.


Margalida A.,Bearded Vulture Study and Protection Group | Moreno-Opo R.,Fundacion CBD Habitat | Arroyo B.E.,Institute Investigacion en Recursos Cinegeticos CSIC UCLM JCCM | Arredondo A.,Fundacion CBD Habitat
Animal Conservation | Year: 2011

Limitation of disturbing activities around the breeding areas of protected species is not always possible, if these activities are economically important and have, in addition, positive effects on protecting the habitats of those protected species. Searching for optimal solutions making commercial exploitation of natural resources compatible with biodiversity conservation is thus of concern to managers and policy makers. This is the case of the cinereous vulture Aegypius monachus, breeding primarily in cork-oak woodland, and cork exploitation, a traditional socio-economic activity carried out in several Mediterranean countries, and critical for the maintenance of this important habitat. We studied the effects of this anthropogenic activity on the behaviour and breeding success of breeding cinereous vultures in Spain. For the adults, the probability of nest abandonment was dependent on the distance of workers from the nest and the level of noise; activities within 500m from the nest were likely to cause abandonment of the nest by adults, if the level of noise was intermediate or loud. Neither the size of the working group nor the use of machines per se, had any effect on the probability of nest abandonment. Pairs in an area of the colony exposed to intrusive anthropogenic activity had 20% lower breeding success than those in the same colony that were not exposed to these disturbances. If the application of buffer zones of 500m is not possible (as is likely given the economic losses involved), several alternatives are recommended based on our results to minimize the impact of these activities, in particular to diminish the noise level of cork extraction activities. Observational studies like this help understanding the magnitude of the problem and finding alternative solutions for harmonizing conservation and economic development. © 2010 The Authors. Animal Conservation © 2010 The Zoological Society of London.


Margalida A.,Bearded Vulture Study and Protection Group | Bertran J.,Bearded Vulture Study and Protection Group
Journal of Ethology | Year: 2010

We examined copulation patterns and associated sexual behaviour in the colonial Eurasian Griffon vulture Gyps fulvus during the pre-laying period. Eurasian Griffon vulture pairs conducted an average of 71.7 copulation attempts per clutch, with an average copulation frequency of 1.2 copulation attempts per day. Low copulation frequencies compared to other raptors and absence of mate-guarding suggest that this species does not possess adaptive behaviour aimed at increasing paternity assurance. However, the gradual increase in copulations during the fertile period is consistent with the sperm competition hypothesis. © Japan Ethological Society and Springer 2009.

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