EN
We investigated whether high−intensity road traffic affects the nestbox occupancy pattern of secondary hole−nesting birds. Field studies were carried out in two forests in south−eastern Poland (Lasy Janowskie forest and Polichna forest). Both complexes were included in NATURA 2000 network. In our knowledge it was first field experiment on road−traffic noise influence on forest birds, conducted in the Polish environmental conditions. The results of this experiment can be used in work on the impact of road projects on forest birds. Nestboxes were hung at twelve linear transects located perpendicularly to the busy road and they were regularly inspected in 2011−2012. Road noise was measured by use of a digital measurer of sound level at each nestbox. Monitoring the activity of predators on the study area was done with the help of digital trail cameras and experiment with use of artificial nest with eggs. Noise level decreased with distance from the road. In the first year of experiment we observed that the birds settled preferentially habitats in the vicinity of road. However in next season the number of occupied nestboxes was independent from the distance from road. We found that the pressure caused by predators on the study area was very low, creating safer nesting places for birds. Our results provide evidence that these birds are well adapted to cope with anthropogenic noise. Some species of birds preferred nesting in neighbourhood of road.