STRATEGY OF THE PYGMY OWL WHILE HUNTING AVIAN AND MAMMALIAN PREY

The hunting behaviour of pygmy owls was studied by following radio-tag ged individuals. There was a seasonal change in their hunting strategy , which involved a switch between hunting mammals in summer and birds in winter. When hunting mammals owls acted as sit-and-wait predators, remaining perched for long periods and quite close to the ground. Hunt ing for avian prey was characterised by shorter perching times on high er perches in the trees. Pygmy owls attack from above, and predation r isk for avian prey appears to be greater in the exterior and lower par ts of a tree. This relative predation risk within the tree is of impor tance in interspecific competition for foraging sites in tits. Intersp ecific niche separation is likely to affect not only the access to foo d but the exposure to predation as well. The exposure gradient may be of importance for adaptations balancing the risk of predation and star vation.