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Summary Movement ecology and environmental factors are topics of paramount importance to consider when planning conservation programmes for target species. Here we discuss this topic by reviewing the available information related to the Egyptian Vulture Neophron percnopterus, with reference to the remnant breeding population of Southern Italy, of high conservation concern and subject of a long-term captive-breeding re-stocking programme. We describe how adverse wind conditions over the Central Mediterranean Sea make the sea-crossing challenging with detrimental effects on the survival of inexperienced birds, and coupled this information with count data of migrating Egyptian Vultures. Furthermore, we indicate how low population size and scarce opportunities in meeting migrating conspecifics could potentially lead juvenile Egyptian Vultures to follow unfavourable migratory routes, with possible repercussions on survival. We postulate how these concomitant factors could be indirectly influencing the long-term survival of this small population, principally affected by anthropogenic threats. We also discuss how the same factors could actually be affecting captive-bred young individuals released in late summer in southern continental Italy, in the framework of the restocking programme. An integrative approach with tailor-made release methods, which also takes into account the age of released birds and geographical and environmental factors, would likely be useful for a more goal-oriented and long-lasting conservation outcome, for the preservation of this endangered scavenger.

Durante la migracion de primavera, algunas decenas de miles de abejeros europeos que invernan en el Africa subsahariana cruzan el Mediterraneo central para llegar a sus zonas de reproduccion en Europa central y oriental. Al hacerlo, concentran el paso a traves del canal de Sicilia, pero eligen diferentes rutas migratorias en respuesta a las diferentes condiciones del viento. Este estudio investigo la influencia de las condiciones del viento local y regional en los patrones de movimiento de esta especie a lo largo del estrecho de Mesina, un cuello de botella migratorio ubicado entre el este de Sicilia y el sur de Italia continental, donde algunas aves rapaces son victimas de la caza furtiva cada primavera. Se realizaron observaciones simultaneas en cuatro puntos de observacion, tres en el lado siciliano y uno en el limite continental (lado calabres). Los vientos del noroeste prevalecieron en el Estrecho durante los dias con pico de migracion. No obstante, los patrones locales levemente diferentes de vientos horizontales y verticales en cada sitio de observacion afectaron la formacion de bandadas y dieron forma al paso de las aves rapaces a traves de este cuello de botella, ampliando el frente de migracion. Los resultados confirman que la magnitud de la migracion primaveral del abejero europeo en el Estrecho se ve fuertemente afectada por los patrones de viento en el canal de Sicilia. En particular, los migrantes se concentran en este cuello de botella despues de cruzar el Canal con vientos del noroeste el dia anterior. En conclusion, al interpretar el comportamiento migratorio tanto a escala local como regional, este trabajo puede ayudar a planificar un seguimiento mas eficiente de los abejeros europeos a traves del Estrecho y mejorar la ubicacion de las acciones de conservacion.

Presence and distribution of ecological barriers shapes the distribution of migratory birds as well as any other living organism. In Italy, short-toed snake eagles (Circaetus gallicus) breed in the northern and western areas of the peninsula but the species is rare in the south or the islands. The Italian population of this species migrates across the Mediterranean at the Strait of Gibraltar rather than crossing the large stretch of sea between Sicily and Tunisia. This suggests that, in Italy, fall migration is oriented south–north and spring migration north–south. In this paper we test the hypothesis that the accessibility of the suitable habitat area along the Italian Peninsula is in relation to the geographical migration pattern of the studied species. We integrated information from the movement ecology, the geography and the traditional ecological features in order to provide an ecological explanation of the current biogeographical pattern of our model species. We compared statistical models with and without latitude as a predictor. Each model was based on ecological and geographical variables, including land use, prey availability, spatial distribution of environmental elements (patch analysis), geomorphology, and geography. These models predict two patterns of suitability for short-toed snake eagles in Italy. Our results suggest that the abundance of this species increases with latitude despite the existence of large areas of suitable habitat in southern Italy. We suggest that the actual distribution of the short-toed snake eagle in Italy is influenced by the particular migration path used by this population, supporting the hypothesis that this species is still colonizing the Italian Peninsula through an unexpected colonization direction from north to south.