2025 Volume 74 Issue 1 Pages 71-78
In 2015, the captive breeding of Japanese Night Heron Gorsachius goisagi was successfully achieved for the first time in Japan. Information on the species' breeding biology is generally lacking because of the difficulty in obtaining detailed field observations. In this study, we recorded detailed information on the reproductive behavior of two captive pairs, the individuals of which were identifiable by their leg bands. The start of the breeding season and the length of the nest building to brood rearing period were consistent with reports on wild birds. Males and females spent approximately the same amount of time for each reproductive behavior. Notably, we documented, for the first time, that pairs made second breeding attempts in the same year, showing that this species is physiologically capable of reproducing twice in the same year. The second breeding attempt began after the first brood fledged, but its progress was disturbed by interactions with the fledglings from the first clutch.
