Investigations are ongoing into the death of about 30 koalas after the bulldozing of a Cape Bridgewater bluegum plantation in February.
Reports suggest over 30 koalas who inhabited the plantation had to be euthanized and dozens of were taken to the Mosswood Wildlife Rehabilitation Centre in Koroit for assessment or treatment.
Centre manager Tracey Wilson confirmed only 13 Cape Bridgewater koalas remained in her care.
"The ones that we have now are smaller," she said. "It's too cold at the moment, we can't release them in winter.
"These ones were dependant when they came in, some needed to put on extra weight but most were just too young to be released.
"They're all looking great now and eating heaps, they're definitely hanging out for release time but we can't just put them anywhere yet."
Mrs Wilson said it was difficult to know how many koalas had been through the centre after the plantation incident as some were transferred elsewhere for care.
Wildlife management and environmental expertise organisation EcoPlan were tracking some of the koalas after their release.
"We certainly haven't forgotten about the investigation though I know Covid has put everything on hold," she said.
"We try to keep our news alive on our social media as much as possible."
The Department of Environment, Land, Water and Planning are investigating the plantation incident and chief conservation regulator Kate Gavens said large amounts of evidence from the location had been examined. Forensic radiography and pathology had also taken place on animals located at the scene.
"Our investigators and experts are making progress with this complex case and we urge anyone with information to contact Crime Stoppers," she said.
Anyone with information can contact 1800 333 000.
Mosswood Wildlife Rehabilitation Centre is a registered shelter and donations can be made via mosswoodwildlife.org.au or its social media pages.
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