Factors Influencing Occurrence of Passerines in the Reed Archipelago of Lake Velence (Hungary)

Abstract

Bird census data from the reed archipelago (109 islands) of Lake Velence, Hungary, were used to assess the relative importance of habitat scale variables (island area and shape, reed stand density and reed height) and landscape scale variables (distance to the nearest reed island and nearest large reed island, percentage of reed-, water- and land-cover around the islands). Habitat and landscape scale variables played a similar general role in explaining the presence of the eight observed reedbed passerines. Reed island area was the most important factor; however, owing to the small average island area (1.74 ha), this simply indicates that too small reed patches were not occupied. A prefer- ence for an elongated shape (reedbed edges) was important for half of the species, and no other variables were includ- ed into the model of more than two species. The important practical conclusion is that both habitat and landscape scale factors should be considered in nature conservation management of reedbeds.