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Sep plowy Gyps fulvus pod Ciechanowem

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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.
A multivariate analysis was carried out in order to investigate the most influential habitat variables and related features in the selection of breeding cliffs by the Griffon Vulture in Crete. The species was found nesting in mid-altitude areas, close to stock-raising units, on high limestone cliffs, which were also well protected against the prevailing winds of the island. A principal components analysis, which explained 53% of the total variance of the variables examined, differentiated Griffon Vulture colonies in relation to their isolation from other colonies, accessibility to humans and proximity to food resources. In addition, a stepwise discriminant function analysis between breeding and random cliffs included the height of the cliff, its substratum, the altitude, and the distance to the stock breeding unit in a model that successfully classified 97.1% of the nesting and 88.2% of the random cliffs. In comparison to continental regions the Griffon Vulture colonies in Crete were located on higher cliffs but at a lower altitude. This fact should be attributed to the species nesting on steep coastal cliffs close to the livestock's wintering areas.
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