ROOST SITE SELECTION IN THE CRANES OF HORTOBÁGY
Abstract
In communal roosts, a large number of individuals aggregate on a given site. These sites provide shelter and protection from predators and are often used for a long time. To protect these areas efficiently, it is highly important to understand the processes which operate during the occupation of roost sites, and to find out what factors determine the selection of core areas. We investigated roost site selection of cranes at the Kondás lake in the Hortobágy National Park. The temporal and spatial distribution of roosting cranes demonstrates that conspecific attraction plays an important role in the microhabitat selection of roosts. Cranes generally prefer reedbed edges and the central open islands of the lake. The main sources of disturbance are anthropogenic factors: the occasional appearance of potential predators did not affect the birds, whereas they were repeatedly observed to be disturbed by human activities.
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