Male quolls that lose their testicles can live twice as long as the rest of the male quoll population.
Jaime Heiniger from the University of Queensland reported this unusual observation at the annual meeting of the Ecological Society of Australia this week.
"I've been studying quolls on Groote Eylandt. One of the males that I was tracking had an accident in which it lost its testicles, but this allowed it to survive to a second year," said Ms Heiniger.
Groote Eylandt, in Australia's tropical Gulf of Carpentaria, is one of the few places quolls now survive because there are no cane toads and fire isn't too frequent or intense.
"Quolls are promiscuous. Males can mate with many different females and in my population can sire up to 34 young. Incredibly, females can produce a single litter with up to six different fathers," said Ms Heiniger. "Males die after such a prolonged sex frenzy, except in rare accidental cases."
Worryingly, quoll numbers are declining on Groote Eylandt, and Ms Heiniger aims to discover why.
"Quolls are keystone predators, and their voracious appetites keep many other species in check. So if quolls are lost from Groote Eylandt, there will be big impacts on the island ecosystem."
"Loss of the Groote Eylandt population would be a major blow because this species is threatened on the mainland, particularly by cane-toads, feral cats and inappropriate fire regimes," said Ms Heininger.
The Ecological Society of Australia is holding its annual meeting in Adelaide, with over 600 delegates participating in 6 concurrent sessions and field trips.
Jaime Heininger 0403685093.