Long-tailed Tit (aegithalos caudatus) Science Article 2
abstract
In the cooperative breeding system of the long-tailed tit aegithalos caudatus failed breeders may become helpers at the nest of another pair to whom they are usually related. The aim of this study was to determine the effect of helping behaviour on the survival of helpers and the recipients of their help. We used capture-mark-recapture data and the MARK program to analyse survival of 482 birds ringed as fledglings and 155 birds ringed as adults. Juvenile males had a higher survival probability than juvenile females across all years whilst their subsequent adult survival was constant. Within sex, the survival probability of juveniles that fledged from nests with helpers was higher than those that did not receive help as nestlings.
Andrew McGowan, Ben J. Hatchwell and Richard J. W. Woodburn, Journal of Animal Ecology 72 (3), 491-499.