Nest-Sites used by Stock DovesColumba oenas: What Determines their Occupancy?

Abstract

Nest-site preferences of the Stock Dove Columba oenas population breeding in holes excavated by the Black Woodpecker Drycopus martius in three sites in western Poland was examined. During the surveys, 176 different trees with 326 holes of Black Woodpeckers were found and investigated. Habitat data at nest locations were characterized on a fine microhabitat scale — hole tree. We used individual selection indices and canonical variate analysis to describe nest-site preferences. Both analyses provided similar results. Nest-site selection of the Stock Dove was consistently associated with live beeches Fagus sylvatica with more than one hole. These features were clearly associated with diameter at breast height. Moreover, holes situated higher in tree trunk were preferred. Dead trees, mostly Scots Pines Pinus sylvestris, were avoided by the Stock Dove. We suggest that positive selection for smooth-barked beech trees with a number of holes, as well as holes situated higher might reduce the risk of predation by arboreal predators, e.g. the Pine Marten Martes martes. The positive selection for live trees, and clear avoidance of the dead ones, may reduce the cost of incubation and thermoregulation. Moreover, the live beech trees have long life expectancy compared to other tree species. Our results provide evidence that large alive beech trees with the number of holes excavated by Black Woodpeckers are necessary for maintaining breeding population of the Stock Dove.