Death After Sex in the Australian Bush

Charleston wasn't just about pizza and beer, though with any scientific conference that's always a part of it ...

First up, we'll hear about Jaime's poster. Jaime did a 1st class honours degree in the lab, studying the way Rhinella marinus (cane toad) tadpoles respond to the presence of predators in their environment. But that's not what she was presenting here ... Jaime also recently was accepted into the PhD program at UQ to study quolls on Groote Eylandt, and she was keen to get the word out there about her new study system.


Now.

More about quolls and sex and the bush, as conveyed by Jaime and her co-authors on the poster, Robbie and Billy {with clarifications from me along the way}

image by Candice Bywater

Death after Sex in the Australian Bush: determinants of survival and reproduction in males of the world’s largest semelparous* mammal {*meaning they die after breeding!}

The northern quoll (Dasyurus hallucatus) is a medium-sized (approx. 1 kg) predatory marsupial previously common across the entire top-end of Australia. This species 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. A small proportion of females will survive to produce a second litter, but there are no documented cases of survival to a third breeding season. The young are born after a short gestation period and then carried in a rudimentary pouch for approximately 60-70 days.


Females will then leave young in dens while they forage, returning to suckle until young are independent at 4 – 5 months. Both sexes are solitary throughout the year with a home range averaging 35 ha for females and approximately 100 ha for males during the breeding season but varies greatly between individuals.


During {Jaime's} study, {she} will be investigating the morphological and performance determinants of both survival to reproductive-age and fecundity among males of this species on Groote Eylandt, an Indigenous-managed island off the coast of the Northern Territory. Northern quolls are still highly abundant on this island and this population offers a unique opportunity to understand the evolution of this extreme mating system and the role physical performance plays in the reproductive success of males.

We can't wait to hear more!