Male Bias in Road-kills of Macropods

Abstract

I determined the sex of a total of 251 road-kills of six macropod species in southern Australia over a 13-year period. There was a significant bias towards males in five species, ranging from 65 to 92% males, but there was no difference from parity in the red kangaroo, Macropus rufus. Male eastern grey kangaroos, M. giganteus, and male western grey kangaroos, M. fuliginosus, probably behave in ways that expose them to vehicles more than females. Male-biased road-kills of swamp wallabies, Wallabia bicolor, may reflect skewed population sex ratios. There are insufficient data on the behaviour and population structure of the red-necked wallaby, M. rufogriseus, and rufous-bellied pademelon, Thylogale billardierii, to determine which explanation is responsible for male-biased road mortality in these species.