Occurrence of extra-pair paternity and intraspecific brood parasitism in the Whiskered TernChlidonias hybrida

Capsule Patterns of parentage were studied in a colony of Whiskered Terns Chlidonias hybrida in central Poland. We assessed the parentage of 64 chicks from 30 broods using five polymorphic microsatellite loci. The rate of extra-pair paternity was estimated at 8.1% of offspring and 11.8% of broods (the upper 95% CL: 16.9% and 27.1%, respectively), whereas intraspecific brood parasitism was recorded in 4.7% of offspring and 10.0% of broods (the upper 95% cl: 9.9% and 20.7%, respectively). The data obtained on the occurrence of alternative reproductive strategies in Whiskered Tern are consistent with general patterns of parentage found in other colonial larids.