156 results on '"Carrascal, Luis M."'
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152. Thermal ecology and spatio-temporal distribution of the Mediterranean lizard Psammodromus algirus
- Author
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Carrascal, Luis M., primary and Diaz, Jose A., additional
- Published
- 1989
- Full Text
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153. Spatio-temporal organization of the bird communities in two Mediterranean montane forests
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Carrascal, Luis M., primary, Potti, Jaime, additional, and Sanchez-Aguado, Francisco J., additional
- Published
- 1987
- Full Text
- View/download PDF
154. Identifying sources of heterogeneity in capture probabilities: an example using the Great Tit Parus major
- Author
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Carrascal, Luis M., Conroy, Michael J., Senar, Juan Carlos, Mozetich, Ingrid, Domenech, Jordi, and Uribe, Francesc
- Abstract
Heterogeneous capture probabilities are a common problem in many capture-recapture studies. Several methods of detecting the presence of such heterogeneity are currently available, and stratification of data has been suggested as the standard method to avoid its effects. However, few studies have tried to identify sources of heterogeneity, orwhether there are interactions among sources. The aim of this paper is to suggest an analytical procedure to identify sources of capture heterogeneity. We use data on the sex and age of Great Tits captured fn baited funnel traps, at two localities differing in average temperature. We additionally use 'recapture' data obtained by videotaping at a feeder (with no associated trap), where the tits ringed with different colors were recorded. This allowed us to test whether individuals in different classes (age, sex and condition) are not trapped because of trap shyness or because of a reduced use of the bait. We used logistic regression analysis of the capture probabilities to test forthe effects of age, sex, condition, location and 'recapture' method.The results showed a higher recapture probability in the colder locality. Yearling birds (either males or females) had the highest recapture probabilities, followed by adult males, while adult females had the lowest recapture probabilities. There was no effect of the method of 'recapture' (trap or video-tape), which suggests that adult females are less often captured in traps not because of trap-shyness but because of less dependence on supplementary food. The potential use o this methodological a roach in other studies is discussed. [ABSTRACT FROM AUTHOR]
- Published
- 1999
155. Cabra montés – Capra pyrenaica Schinz, 1838
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Alados, Concepción L., Escós, Juan, Salvador Milla, Alfredo, Cassinello, Jorge, Travesi, R., Carrascal, Luis M., and Sociedad de Amigos del Museo Nacional de Ciencias Naturales (España)
- Abstract
Mamíferos - Orden Artiodactyla - Familia Bovidae en la Enciclopedia Virtual de Vertebrados Españoles, http://www.vertebradosibericos.org/. Versiones anteriores: 8-10-2003; 21-12-2004; 26-01-2005; 10-04-2007; 10-06-2008; 25-01-2012, A comprehensive review of the natural history of the Spanish Ibex Capra pyrenaica Schinz in Spain.
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- 2015
156. Beyond average temperature: distribution of wintering birds at multiple scales
- Author
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Villén Pérez, Sara, Carrascal, Luis M, Seoane, Javier, Carrascal de la Puente, Luis M., Seoane Pinilla, Javier, UAM. Departamento de Ecología, and CSIC. Museo Nacional de Ciencias Naturales (MNCN)
- Subjects
Aves - Factores climáticos - Tesis doctorales ,Medio Ambiente - Abstract
208 páginas y 7 capítulos.- Tesis Doctoral defendida en la Universidad Autónoma de Madrid el 3-12-2013. Calificada de Sobresaliente cum laude, [EN] Aim To disentangle the subtleties of the relationship between the thermal environment and the distribution of wintering birds, at multiple spatial scales. Specifically, to analyze the relative influence of temperature on species distributions, its interaction with various thermal and non-thermal factors, and the context-dependence of these relationships (i.e., species, season and geographical location). Location Iberian Peninsula and Guadarrama Mountain range (central Spain). Methods I use observational and experimental field approaches to control for habitat structure, topography, food abundance and predation risk, from forest patches to landscape, regional and peninsular scales. Fieldwork is carried out with woodland passerines inhabiting mountain oakwoods of Quercus pyrenaica, and subtle variations in temperature and wind are precisely measured with data loggers. Main results and conclusions Wintering birds respond to natural variations in temperature at multiple scales, selecting the warmest forest patches to forage and the warmest mountain areas and peninsular regions to overwinter. However, temperature per se accounts for a relatively small proportion of the variation in species distribution patterns. Indeed, a sudden extreme drop in temperature is not enough to alter species abundances, or to promote their general redistribution to minimize wind chill. Other non-thermal environmental factors like vegetation structure, predation risk and availability of predictable food resources, seem to be more deterministic in driving winter species distribution than direct measurements of temperature. On the other hand, the influence of the thermal environment goes far beyond average temperature: minimum night temperature, incident sun radiation and altitude related with snow cover are key drivers of species distributions. The relative relevance of all these factors depends on the ecological scenario, varying across species, seasons and geographical locations. I conclude that if we disregard other environmental effects, we will overestimate the influence of temperature on species abundance and underestimate the plasticity of these to respond to temperature changes. Applications and prospects Fine-grained approaches, based on direct measures of the study organisms and carried out through precise local measurements of environmental variables, are needed to understand the functional mechanisms driving species distribution patterns at wider scales. At all scales, we need to control for other environmental factors when predicting the responses of birds to temperature, under either current or future scenarios of global warming. Otherwise, we are at risk of generating strongly biased predictions that will inflate the magnitude of climate change effects., [ES] Objetivo: Desentrañar los pormenores de la relación entre el ambiente térmico y la distribución de aves invernantes a múltiples escalas espaciales. En concreto, analizar la influencia relativa de la temperatura en la distribución de especies, su interacción con varios factores térmicos y no térmicos, y cómo tales relaciones dependen del contexto ecológico (i.e., especies involucradas, estación del año y localización geográfica). Localización Península Ibérica y Sierra de Guadarrama (centro de España). Métodos: He utilizado tanto aproximaciones observacionales como experimentales de campo para controlar el efecto de la estructura del hábitat, la topografía, la abundancia de alimento y el riesgo de depredación, en escalas que varían desde el parche hasta el paisaje forestal, la región de Guadarrama y la Península Ibérica. El trabajo de campo se ha llevado a cabo con paseriformes forestales de robledales montanos de Quercus pyrenaica, y las variaciones de temperatura y viento se han medido de forma precisa y local con registradores de datos. Resultados y conclusiones principales: Las aves invernantes responden a variaciones naturales en la temperatura a múltiples escalas, seleccionando los parches forestales más cálidos para forrajear y las áreas de la sierra y de la península más cálidas para pasar el invierno. Sin embargo, la temperatura “per se” explica una proporción relativamente pequeña de la variación en los patrones de distribución de especies. De hecho, una caída extrema y repentina de la temperatura no es suficiente para alterar la abundancia de las especies, ni para promover su redistribución general hacia las áreas con una sensación térmica más alta. Otros factores ambientales como la estructura de la vegetación, el riesgo de depredación y la disponibilidad de fuentes predecibles de alimento, son más deterministas en la distribución invernal de especies que las medidas directas de temperatura. Por otro lado, la influencia del ambiente térmico va más allá de la temperatura promedio: la temperatura mínima nocturna, la radiación solar incidente y la altitud relacionada con la cobertura de nieve son determinantes clave en la distribución de las especies. La importancia relativa de todos estos factores depende del escenario ecológico, variando a través de las especies, las estaciones del año y de las localizaciones geográficas. Mi conclusión es que si no consideramos otros efectos ambientales, estaremos sobreestimando la influencia de la temperatura en la abundancia de especies y subestimando la plasticidad de estas para responder a cambios de temperatura. Aplicaciones y perspectivas: Las aproximaciones de detalle, basadas en medidas directas de los organismos de estudio y en medidas locales precisas de las variables ambientales, son necesarias para entender los mecanismos funcionales que dirigen los patrones de distribución de especies a escalas mayores. A cualquier escala, necesitamos controlar la influencia de otros factores ambientales sobre la respuesta de las aves a la temperatura, bajo escenarios tanto actuales como de cambio global futuros. En caso contrario, corremos el riesgo de generar predicciones fuertemente sesgadas que inflen la magnitud de los efectos del cambio climático., This thesis has been supported by a Formación de Personal Investigador grant (FPI; BES- 2009-029386) associated to the project CGL2008-02211/BOS of the Spanish Ministry of Economía y Competitividad.
- Published
- 2013
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