Urban breeding Herring Gulls: aspecs of biology in Lorient (Britanny, France)

摘要

A ten-year study of urban breeding Herring Gulls has been carried out in Lorient, Britany (France). The nests of the main group are found on a sloping roof, and density remains low (0.3 to 1 nest per 100 square metres). The average date of breeding (around the 1 super(st) of May) is almost the same as in natural breeding sites elsewhere in Britany; few late clutches are laid. Fledglings leave the colony before mid-July. Neither predation nor cannibalism occurs, and the production of 1.4 fledglings per nest is higher than in natural sites.