Occupancy rates and nesting success of European storm-petrels breeding inside artificial nest-boxes

Abstract

We report on occupancy rates and nesting success of European storm-petrels Hydrobates pelagicus breeding in artificial nest-boxes for five years. Plastic nest-boxes were installed inside two natural caves on the island of Benidorm (western Mediterranean), where breeding colonies of the species occur. The location of nest-boxes was (a) over exposed natural nests or (b) at sites without nests, but usually close to them. Nest-boxes were visited during the breeding season following installation, when only nest-boxes over old nests were occupied. Occupancy rates in both types of nest-box increased gradually year after year, reaching 29% in the fifth year. Nesting success of pairs breeding inside boxes was higher than nesting success of pairs breeding at natural sites.