By Bridie Smith and Science Editor
He was quite the catch: young, good looking and fit. Spotted lounging in a tree not far from the edge of a road, this koala was a welcome addition to a study that hopes to shed light on why the Somers koala population is in decline.
Though he put up a bit of a protest initially - growling and snorting in a most undignified way - the young male koala was largely co-operative as three researchers coaxed him down to the ground.
Once secured in a hessian bag, he was weighed, measured and given a GPS collar to wear.
He also had a skin sample taken from his left ear for a DNA bank. He passed a quick assessment of his condition with flying colours; getting a solid eight out of 10 for his shoulder muscles and perfect 10 for his coat.
Deakin University researchers Desley Whisson (left), Kita Ashman (centre) and Darcy Watchorn measure a young male koala's head length.Credit: Justin McManus
The female koala sitting in the treetops a few hundred metres away could do a lot worse. But what has researchers puzzled is that the next generation of Somers koalas aren't arriving.
In almost a year of monitoring, Deakin University biologist Desley Whisson hasn't recorded a single joey living among the well-treed gardens of the seaside township 86 kilometres south-east of Melbourne.
Instead, most of the koalas in Somers are older, with an average age of seven.
Exactly why the koala population is in decline is a mystery. Though Dr Whisson has her suspicions.
This young male koala had a GPS collar attached so researchers can study his movements.Credit: Justin McManus
Increasing traffic and development, as well as dogs and disease, could all be contributing to the area's joey drought.
The young male caught on Thursday will join the cohort that researchers are studying to learn about urban koala populations in Victoria, of which very little is known.
The male koala caught in Somers on Thursday was weighed, measured and given a GPS collar to wear before being released.Credit: Justin McManus
Since last March when 16 koalas were fitted with radio collars, Dr Whisson and her team have learnt that the urban koalas in Somers travel far greater distances than their forest counterparts.
The small population that call Somers home roam about seven hectares over a month. In one case, a male nicknamed Romeo was tracked travelling through 133 properties. By comparison, the koalas in the Otways tend to stick to a hectare.
This aerial view shows the parts of Somers Rosie the female koala (pink) and Romeo the male koala (grey) call home. The dotted lines indicate their preferred areas. Credit: Desley Whisson
"That's a big difference," she said.
Dr Whisson suspects this is because the small population around Somers have to travel further to find a mate. Travelling greater distances exposes the animals to more threats, including roads, cars and dogs.
But there's no reason why koalas and people can't co-exist. Dr Whisson said the information gained from the ongoing study could inform the way the urban area is managed to benefit both types of locals.
"There's a lot of things that can make a difference, from planting certain trees to building timber rather than metal fences, so koalas can use them to move around out of reach of dogs," she said.