Intraspecific adoption and foster feeding of fledglings in the North Island robin
Intraspecific foster feeding and adoption has rarely been observed in birds, with the exception of waterfowl. In this study, I document for the first time the existence of intraspecific foster feeding and adoption of fledglings by adult passerines with their own young. During a three-year study of the North Island robin (Petroica longipes), a species with very low levels of extra-pair paternity, eight fledglings (4% of the fledglings in the population the study years) were fed by adults other than their parents, with four of these being adopted.