Scramble Competition Polygyny in Platypuses.

Abstract

Platypuses in the Upper Hastings river catchment, near the village of Ellenborough, mid-north coast of New South Wales, occur in small numbers in pools and raceways. Visual observations of platypuses at dawn and dusk during winter-spring breeding seasons included males that wandered, mate searched and attempted forced copulations. No intrasexual aggression between males was observed. Choosy female platypuses seemed to be able to control where and when males could mate. Rare observations of aggression among female and/or juvenile platypuses during summer may have been related to resource defence. Platypuses appear to fit the scheme of 'resources influence female dispersion influences male dispersion'.