EFFECT OF ROAD TRAFFIC ON THE BREEDING SITETENACITY OF MALE WILLOW WARBLERS (PHYLLOSCOPUS-TROCHILUS)

The breeding site-tenacity of colour-ringed male Willow Warblers (Phylloscopus trochilus) was studied in an homogenous area of 154 ha, which is crossed by a heavily travelled road (45 000 cars per day). Close to the road (< 200 m) the dispersal of the males is much higher than for birds further away. There is also some evidence that most of the near-to-the-road males are yearlings. The differences indicate that adjacent to the road the habitat is less favourable for the Willow Warbler and can be considered as marginal.