Birds living on the edge : power-line corridors influence on avian communitites in Norwegian secondary coniferous forest

Abstract

Power-line corridor edges differ from other edge habitats by its long shape with a high amount of edge habitat compared to open fields, and the regular maintenance clearing the corridor for forest trees not allowing forest re-growth. Power-line corridors in northern boreal secondary coniferous forests have a low avian abundance compared to the adjacent edge habitat. Bird species associated with open fields and clearings do to a very little extend appear in the power-line corridor. The edge habitat does have the highest avian abundance and richness compared to both the corridor habitat and the adjacent forest interior. Species abundance is highly influenced by the forest development classes, where most birds are found in the middle classes where forest net primary production is highest.