Ornis Hungarica. vol.10. (2000) p.41-48.
Nest predation experiments in the Tököl forest, Central-Hungary: the role of edges
As a result of human perturbations, forested landscapes in central Europe have an increased amount of edge, and the importance of edge effect has been increasing. One important factor of edge effect is nest predation, which is usually higher along edges than inside fragments. We investigated the predation of artificial nests in a forest in an agricultural landscape during April-May 1999. Artificial ground, and shrub nests were used, with one quail and one plasticine egg placed in each nest. Plasticine eggs were used to identify nest predators, and to detect predation by small mammals. We compared predation of ground, and shrub nests, and investigated the effect of concealment on nest predation. Predation on artificial nests in shrub was significantly lower along the forest edge than inside the forest, probably caused by the very dense vegetation cover along the edge, which concealed the nests. Predation on ground nests did not differ significantly between the forest edge and forest interior. Predation was high in the field edge, and decreased with increasing distance from the edge. Predation rate did not differ significantly between different edges. It seems that vegetation density influences nest predation in the investigated area. There was no difference in predation between the pooled ground and shrub nests. Ground nest predation was mainly due to small mammals, shrub nest predation was mainly caused by birds.