Five breeding attempts of male Common Kingfisher (Alcedo atthis) during the season consisted of pairing with two females

In 2018, the unique breeding effort of Common Kingfisher was documented in the Danube River system, southwestern Slovakia. Preliminary observations indicated that one breeding pair managed to breed five times of which three attempts were successful. The aim of the present work was to determine whether the observed breeding pair exhibiting remarkable reproductive parameters did not undergo extra-pair interactions or partner exchange during a long breeding season using molecular techniques. Our results show, that male bred not with one, but with two females in sequence during the season. Male found a new mate during the incubation of the third brood. Due to the relatively short distance between nesting burrows and raising many offspring from both broods, we assume that the possibility of simultaneous bigamy is relatively low. Since the females very rarely leave males during breeding, we suggest that exchange of the female partner was due to a loss of the partner rather than a consequence of an abandonment by the female.