Meeting Abstract
P2.1 Saturday, Jan. 5 The life and times of a sex addict in northern Australia: understanding the breeding dynamics of the world’s largest semelparous mammal HEINIGER, J*; DICKMAN, C; WILSON, R S; The University of Queensland; University of Sydney; The University of Queensland r.wilson@uq.edu.au
The northern quoll (Dasyurus hallucatus) is a medium-sized (approx. 1 kg) predatory marsupial previously common across the entire top-end of Australia. It is the largest known semelparous mammal in the world, which means mating is highly synchronous, males live for only one year, and males undergo total die-offs soon after the mating season. Such population-wide male die-offs are presumably due to the physiological stress of procuring copulations and the intense fighting among males. Despite large population declines on mainland Australia a thriving population is found on Groote Eylandt, an Indigenous-managed island off the coast of the Northern Territory that is free of the invasive species linked to the rapid decline in mainland populations. During the past year a mark-recapture study was conducted on Groote Eylandt to determine the population dynamics, ecology, reproductive output and performance of 150 individuals found within a 125ha area on the island. We have found that this high-density population is sex-biased towards females and there are large morphological differences among males with consequences for their biting and running performance. Interestingly, some of the males of this population survive for an extended period past the breeding season (previously extremely uncommon in this species) and their condition appears to recover after the abrupt weight loss and decline in condition that accompanies the intense mating bout. In the upcoming field season we wish to determine the parentage of all pouch young and discover what combination of male traits (morphology and performance) equates to a siring a greater number of young. We also aim to determine why some males die immediately after the breeding season while others have the ability to live past this point.
