Genetic relationships of Cory's Shearwater: Parentage, mating assortment, and geographic differentiation revealed by DNA fingerprinting

We used DNA fingerprinting to assess genetic structure of populations in Go ry's Shearwater (Calonectris diomedea). We analyzed mates and parent-offspr ing relationships, as well as the amount and distribution of genetic variat ion within and among populations, from the level of subcolony to subspecies . We found no evidence of extrapair fertilization, confirming that the gene tic breeding system matches the social system that has been observed in the species. Mates were closely related, and the level of genetic relatedness within populations was within the range usually found in inbred populations . In contrast to previous studies based on allozymes and mtDNA polymorphism , DNA fingerprinting using microsatellites revealed consistent levels of ge netic differentiation among populations. However, analyzing the two subspec ies separately revealed that the pattern of genetic variation among populat ions did not support the model of isolation by distance. Natal dispersal, a s well as historic and/or demographic events, probably contributed to shape the genetic structure of populations in the species.