PATERNITY AND PATERNAL BEHAVIOR IN THE RED-WINGED BLACKBIRD, AGELAIUS-PHOENICEUS

The relationship between paternity and male parental behaviour was inv estigated in an eastern population of red-winged blackbirds. Data coll ected over four seasons revealed substantial variation in paternity an d the frequency of male provisioning. The feeding of nestlings by male s increased non-linearly with the age of the nestlings but did not dif fer within or between seasons. Average relative provisioning by males to individual nests was not associated with the proportion of nestling s sired by the territory owner (determined through multi-locus DNA fin gerprinting), either in a bivariate analysis or a multivariate analysi s with those variables found to be associated with male parental care in other studies of red-winged blackbirds. Males provisioned significa ntly less frequently at nests of order females, but paternity was not associated with female age. The later in the season a female settled, the higher her mate's paternity in her brood, yet male provisioning wa s not associated with female settlement date. Estimated total provisio ning by males (sum of all feeding trips over ah nests in each male's t erritory) was not associated with average paternity in bivariate and m ultivariate analyses. Total provisioning by males was positively assoc iated with the number of days in the season the male had a brood in a bivariate test, but not with male age, the number of females nor male condition in either bivariate or multivariate analyses. The lack of a relationship between paternity and paternal effort fits predictions of recent theory on the potential effects of reduced paternity on patern al behaviour given (1) the lack of consistent patterns of paternity am ong nests of different order, time of season and male and female age a nd (2) generally weak associations between possible behavioural cues a bout paternity and actual paternity.