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Little is known about the spatial ecology and ranging behaviour of vultures in Europe. In this paper we used GPS satellite telemetry to assess home-ranges of eight non-breeding Eurasian Griffon Vultures in Spain, trying to answer the main questions on when (i.e. the time of the day), how far (i.e. hourly and daily distances) and where vultures range (i.e. home-range size). Results indicated that vultures ranged extensively mainly in areas where traditional stock-raising practices and pasturing were still common, also including some vulture restaurants, which were visited occasionally. Eurasian Griffon Vultures concentrated their hourly and daily movements in the middle of the day, when the availability of thermal updrafts was higher, favouring foraging activities. The overall foraging range, calculated as Minimum Convex Polygon (MCP) (7419 km2), or as 95% and 50% kernel contours (4078 km2 and 489 km2, respectively), was higher than those reported in previous studies. The precise knowledge of the ranging behaviour and spatial parameters is particularly important for the conservation of scavenger species inhabiting human-dominated areas where human activities may jeopardize vulture populations in the long term.
During 2008-2011, nine juvenile Saker Falcon Falco cherrug females were tagged with satellite transmitters in Slovakia. Satellite telemetry provided new insights into the juveniles' movements. In this study we present the use of temporary settlement areas (TSAs) during the movement of the tracked juveniles. We characterized natal areas (NAs, the first TSA in the life cycle of juvenile, restricted to the nest) and TSAs as areas where the distance between the all- night perches did not exceed ten kilometres and where a particular bird spent at least five consecutive days. In these areas 3 types of polygons were identified in relationship to the area of use — a home range (95% kernel polygons), a core area (50% kernel polygons) and an overall used area (100% minimum convex polygons). The overall used areas were highly variable and probably influenced by exploratory flights, when sakers fly out of their home ranges and come back at night. Habitat preference was then analysed in the TSAs for a better understand of juvenile habitat requirements. For habitat preference a CORINE raster image (version 13/2006) with a resolution of 100 x 100 m was used. In the TSAs 14 habitat categories were recorded, but for statistical analysis only 8 habitat categories were used. Conservation status of the NAs and TSAs was also described. Arable land represented the dominant habitat category in the TSAs (mean 67.64% for overall used areas, and 80.94% for core areas). A significant difference was found in the habitat structure of the overall used areas, the home ranges and the core areas. All of the tracked Saker Falcons preferred arable land, while avoiding two habitat categories — forests and scrub and/or herbaceous vegetation associations. The number of days spent in the TSAs (9-139 days, mean = 46.7 days) and in the NAs (36-134 days, mean = 62.3 days) varied by different individuals. Most of the NAs and TSAs are at least partially covered by protected areas, only four areas had no conservation status.
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