Modelos de distribución para el águila perdicera (aquila fasciata) a diferentes escalas espacio temporales. Implicaciones en su gestión y conservación/distribution models for bonelli's eagle (aquila fasciata) at different spatio-temporal scales. Implications for management and conservation

Resumen

This thesis highlighted that species distribution modelling is not only central to both fundamental and applied research in biogeography, but also to studies of conservation biology, ecology, and wildlife management. The obtained models permitted estimation of species¿ ecological requirements, although the extent to which causal relationships between species distributions and the predictor variables were unveiled depended on the adequacy of the predictors used for model building and also on the quality of the distribution data used. A modelling method based on logistic regression was used, which has been demonstrated to be a powerful tool that produces robust models, and is broadly used in the predictive modelling of species¿ distributions starting from presence/absence data. As classi¿cation success using logistic regression is sensitive to the relative proportion of presences and absences in the sample, and the prevalence of Bonelli's Eagle was always different from 0.5, we used the favorability function, whose results are not affected by an unequal proportion of presences and absences. This point opens the door to applying fuzzy logic to species distribution models, with conceptual and operational consequences that were particularly important when contemplating the possibility of evolution in the forecasting of future distribution of the species in climate change scenarios. From the estimation of potential Bonelli's Eagle's distribution and the specification of how much of the variation of the models was explained by each of the considered factor the implications of this thesis have extended from biogeography to diverse areas of research such as conservation biology and the study of potential impacts of climate change. The implications of what at first glance could be viewed as a mere mathematical modification (the use of favourability instead of probability or suitability values) make ecological sense when a direct and significant relationship between presence-absence data, avorability values and upper limit of local abundance is shown. Once demonstrated that the results of our models, from presence-absence data, provide useful information on spatial patterns of abundance, the implications of the results obtained in the different chapters of the thesis can be a significant advance in the field of conservation biology.