It comes amid renewed concerns from experts and environmentalists that the koala is now at risk of being functionally extinct, with koala populations estimated to have halved since the early 2000s.

In April last year, director of development and growth Natalie Robertson claimed council had commissioned a consultant to assess the koala overlay in the city's planning scheme, which exists to protect the local koala population and habitat.

"We have engaged a consultant to review the overlay itself and the policy to give us some understanding of the koala movement through the area," she said in response to concerns raised by Friends of Canadian Corridor (FoCC) president Bob Hartmann.

Three weeks ago, the same consultant's review was again referenced by Ms Robertson, who told The Courier the "consultant's findings will inform" the City of Ballarat's new biodiversity policy and strategy, which is yet to be formalised.

When asked to provide a copy of the consultant's report or, at minimum, the findings of the consultant's report, the City of Ballarat refused without giving a reason for the decision. When pressed to provide a reason, council again declined.

It's since emerged, through freedom of information, that not only does the report not exist, but that the consultant's review was never, in fact, commissioned.

FoCC convenor Jeff Rootes expressed little surprise at the revelation, saying he would have been more astonished to find that environmental groups, such as the FoCC, had been excluded from any such review.

"Quite simply, if there was an inquiry into the environmental overlay, surely we would have been involved," he said.

Nevertheless, the revelation hangs a question mark over the transparency of the City of Ballarat and, more specifically, the fate of its separate promise to embed a koala committee within council.

That promise, repeated on numerous occasions since the inception of council's 2006 koala plan, was reframed by Ms Robertson a few weeks ago as no longer a promise but a possibility contingent on the overall form of council's future biodiversity policy and strategy.

"The consultant's findings [into the koala overlay] will inform the biodiversity policy and strategy, and a koala committee could be formed by [its] outputs and findings," Ms Robertson said in a statement.

As recently reported, environmental groups, including the FoCC, have long-lobbied for a koala committee, which they say is required to prevent council planners from ignoring or diminishing the protections provided by the koala overlay in the planning scheme.

Noting this, Mr Rootes said council planners too often privileged the views of developers above community knowledge with respect to koala movements and habitat.

"The balance is tilted towards developers - council is too influenced by them, particularly in heavily vegetated areas," he said.

"When we put in objections to a development about an area containing koala habitat, we get nothing - no calls," he added. "But when we have had calls, and there's two or three examples of that, we get good outcomes.

"The number of koalas has declined, and they've declined for several reasons, but one of the key reasons is urban incursion into koala areas - loss of habitat."

In contrast to other states and territories, such as Queensland, New South Wales and the ACT, where the koala is officially recognised as endangered under federal environment legislation, the marsupial is denied that status in Victoria.

Marking Save the Koala Day on Friday, Australian Koala Foundation chair Deborah Tabart said this anomaly owed to unrealistically rosy estimates of koala populations in the state, the most recent estimate of which is 450,000, up from 73,000 in 2010.

"There is not enough habitat [in Victoria] for that many koalas," she said.

Since white settlement, over 80 per cent of the koala's natural habitat has been lost, with much of the remaining 20 per cent located on privately owned land.

Mr Rootes said this sheeted home the overriding reason council planners ought to ensure the objectives of the koala overlay are met with precision.

"Council's intention should be 'how do we keep our koalas in Ballarat', not 'how do we let developers knock down koala vegetation for a fast buck'," he said.

"We really need council to be stronger in its advocacy in actually protecting koalas and environmental corridors."

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