BUYING up farms in northwest Victoria to conserve a vulnerable bird species has so far been a disaster, as CHRIS McLENNAN reports
Sheep are the unlikely heroes in a real-life drama to save the threatened Plains Wanderer.
Once derided as environmental vandals, farm animals are again grazing national parks but some fear it may already be too late.
More than 11,000ha of farmland has been bought across the Mitiamo and Kerang areas in Victoria's northwest in the past 20 years and turned into parks because agriculture was said to threaten the survival of some native species.
Now, that policy has been turned on its head after a dramatic decline in numbers of the Plains Wanderer, with neighbouring farmers being asked to run their sheep free of charge across the parks.
Where scientists once considered sheep the enemy of the Australian bush, they are now considered a necessary management tool.
Farmers were offered cash inducements to leave the northern plains because agriculture, particularly cropping and grazing, were thought to be threatening the future of native species. But after surviving alongside farming for 150 years, the quail-like Plains Wanderers are now gone, apparent victims of a bungled environmental policy.
A decade of drought masked the failure of the policy but a succession of wet years saw native grasses grow unnaturally thick for the tiny birds.
The state's expert on Plains Wanderers, ecologist David Baker-Gabb, travelled to the Terrick Terrick National Park last month to check on their progress.
"I couldn't find one, they're gone," Dr Baker-Gabb, a former director of Birds Australia and manager of threatened fauna for the former Department of Conservation and Environment, said.
He is an adviser to Trust for Nature and consultant to federal and state governments.
"The horse has bolted - they needed to have more sheep in these parks," he says.
Other environmentalists want urgent research into the effect of fire, a build-up of native grazing animals such as kangaroos and mechanical slashing.
When the land buy-up hit its straps a decade ago experts thought there were about 500-1000 Plains Wanderers in Victoria after more than a century of farming in the area.
However, Trust for Nature said not all surveys were complete. The group still hopes to find some birds on its properties in the Avoca Plains area near Kerang.
Dr Baker-Gabb said there have been some sightings on private land in the past year and he hopes some of the birds have flown north to Queensland.
Notably, the sightings on neighbouring farms have been in areas that have been constantly grazed.
The experts admit to being caught short after the long drought, when Plains Wanderers numbers were still strong, which was followed by a succession of wet years.
The frightened little birds need "inter-tussock spacings" to thrive.
These are essentially tunnels through the grass to give them cover to move around.
"As well as overgrazing, undergrazing can be a problem, allowing biomass to accumulate to a point where inter-tussock spaces are crowded," a government research report says.
Newspaper articles at the time said the north-central farms were being bought to "remove grazing pressure" on the Plains Wanderers. Today's advice is more about the removal of cultivation and cropping.
"Based on advice from expert scientists, it was determined there was a special situation where sheep grazing should continue under certain circumstances in order to protect these conservation values in order to reduce biomass, as some of the threatened species (such as Plains Wanderer) require open areas," Parks Victoria's manager of conservation research Tony Varcoe said.
"The challenge has been to get the appropriate conservation-based grazing regime in the right place at the right time, and DSE and PV have been taking advice from a technical group on an appropriate grazing regime."
Mr Varcoe said the Plains Wanderer population has been declining generally in Victoria and NSW during the past few years.
"Parks Victoria has been conducting bi-monthly surveys since the end of 2009 to the present. While no Plains Wanderers have been observed as part of these surveys since March 2011, they have been observed by local experts such as David Baker-Gabb.
"While there has been a decline in the population to levels which are of concern, there is no evidence of the species becoming extinct," Mr Varcoe said.
"Sheep grazing is a very effective environmental management tool to maintain suitable habitat for threatened flora and fauna."
Dr Baker-Gabb said more research was needed on how much grazing was needed in the grasslands for the Plains Wanderer.
"Locking out livestock obviously doesn't work for them," he said.
"They seem to get along just fine in a normal year but not so much in a drought year.
"Now an even bigger problem is the lack of grazing, there's not enough sheep and they seem to do the best job."
Dr Baker-Gabb said buying farms and closing the gate had not worked.
"The grasslands need to be managed a lot better than we are doing at the moment."