Philopatry, Nest-Site Fidelity, and Reproductive Performance in Buffleheads

I examined the consequences of breeding-site fidelity and natal philopatty on reproductive performance in Buffieheads (Bucephala albeola).Return rates of breeding females averaged 44% over 4 years.Females were twice as likely to return after their second breeding year than after their first.This difference was not associated with a poor reproductive performance in the previous year because birds that failed to return to the study area had a reproductive performance similar to those that returned, irrespective of breeding experience.Probability of return for successful breeders (45%) did not differ significantly (P > 0.1) from failed nesters (29%).However, nest-site fidelity was high (68%) and was associated with nesting success because successful breeders (83%) were much more likely to reuse the same nest site than were failed breeders (29%).Nest-site fidelity provided some benefits to females.Birds who used the same site laid earlier and laid more eggs.The return rate of females banded as ducklings was 13% in the first two years after banding.Natal philopatty was strongly female-biased and no male ducklings were known to have returned to the study area.The average distance of natal dispersal for returning females was 0.99 km.My results supported Rohwer and Anderson's (1988) prediction that female ducks should gain in terms of reproductive success by returning to a familiar area.