Carrion Crow (Corvus corone corone) Science Article 5
abstract
The effect of group size and the number of helpers on reproductive success is crucial to understand theevolution and maintenance of cooperative breeding. In northern Spain, carrion crows form kin-groups(three to nine individuals) where up to five individuals contribute to rearing the young
DANIELA CANESTRARI et al, ANIMAL BEHAVIOUR, 2008, 75, 403-416