In one corner, a heavyweight tag team of ecologists, environmentalists, researchers and animal rights activists.

In the other, an equally muscled powerhouse of regulators, lawmakers and developers.

In the middle, weighing in at up to 14kg, munching on eucalypt leaves, nodding off for 16 hours a day and blissfully unaware of the rumpus around them, Australia's koala.

The future of the unique arboreal marsupial is again under fierce scrutiny in an inquiry by the Senate environment committee, and through a decision federal Environment Minister Tony Burke will make by November on whether to declare the koala a threatened species.

In this process the koala's greatest problem may be uncertainty: Burke's department has advised against a "threatened" status, noting significant gaps in knowledge about the animal's national population.

Koala advocates agree much more research is needed, but argue that given the truckload of threats to its survival, delaying greater protection could be disastrous. Attached to the debate are planning laws, major developments, the design of transport systems and the established value of the koala to national, state and local economies.

Research by the Australian Koala Foundation found the marsupial's contribution to tourism includes 9000 jobs and and an economic value as much as A$2.5 billion ($3.1 billion) a year.

"The koala is unmistakably Australian," Dreamworld life sciences manager Al Mucci told the Senate inquiry. "This makes koala conservation an imperative of more than just biological and cultural concern, but an issue of national identity, international image and reputation."

No one is in any doubt real problems exist, even if accurate population figures are not available. The latest national estimate is between 43,515 and 84,615, mostly in southeast Queensland and northern New South Wales.

In Queensland state Environment Department research revealed a "dramatic collapse" in populations in the Koala Coast, southeast of Brisbane, with numbers falling by more than 50 per cent in three years to 2008. Mucci said trends suggested the koala was being driven towards extinction.

In central Queensland, Dr Alistair Melzer, of Central Queensland University's Koala Research Centre, said koala populations had contracted or collapsed during a decade of drought and tree death in the 1990s.

The reasons for the alarming decline have been well documented: loss of habitat, injury or death from traffic or dogs - between them accounting for more than 4000 a year - pesticides and fertiliser runoff, overcrowding and increased competition for food and territory, and disease - especially chlamydia and koala retrovirus.

Climate change is regarded as an increasing threat.

The official response has been fragmented and, according to critics, inadequate. The federal Government has no specific legislation yet to protect the koala, other than listing as a native species.

In New South Wales, the koala is a declared vulnerable species, while South Australia supports listing the species as vulnerable - so long as it does not include introduced populations.

In southeast Queensland, koalas are a vulnerable, protected wildlife throughout areas from the NSW border north to Gladstone and west to Toowoomba, with more than A$50 million ($62.8 million) committed so far to a koala crisis response strategy.

This includes a requirement for state agencies to include koala conservation in their plans and regulatory processes.

But the Senate inquiry has been told that management has been left in the hands of the states and lacks a consistent national approach.

Even the comprehensive Queensland measures, the Koala Action Group told the inquiry, have been "spectacularly ineffective".

In northern NSW, conservationists in Byron Shire said critical koala habitat had been "blatantly removed and destroyed", with more to come.

They said the last remaining eastern wildlife corridor on the Australian mainland, connecting the Mt Warning caldera to coastal reserves, was inadequately protected and was now under threat of further development.

In Queensland, the state Wildlife Preservation Society said that in spite of regulations and legislative powers - rarely or infrequently used - urban development was allowed to expand into known key habitat.

State agencies continued to ignore management requirements, the inquiry was told.

The Education Department, for example, had sold land supporting a significant koala community to a private organisation, Queensland Rail had cleared significant mature koala food trees in Ormiston, an area already under pressure from urban expansion, and land had allegedly been illegally cleared in a koala conservation area.

Koala habitat had been handed over for housing, industrial estates, quarries and sand mining - "all under the watchful eyes of state government agencies".

But moves to tighten controls and declare koalas a threatened species are being opposed by other interest groups, such as the Property Council of Australia, representing developers, construction companies, financiers, and investment property owners and managers with combined assets of more than A$300 billion ($377 billion).

The council said in its submission to the inquiry that while it supported the protection of "an icon of Australia's fauna", virtually no work had been done to examine the size of the koala population and its present habitats.

Nor had there been any specific scientific mapping to determine whether the koala was really under threat.

The council said listing the koala as a threatened species would hit local economies, increase the cost of affordable housing, lead to poorly planned communities and strip landowners of basic rights, without compensation.

"The use of the mechanism of a prohibition on development and land use is a blunt and draconian tool," it said.

Koala economy

Jobs in the tourism sector linked to visitors seeking out koalas

$1.3 billion
The minimum economic contribution spun off from koala-related activities. The upper range is a hefty $3.1 billion