The human impact on koala numbers is debated but there is no doubt logging, such as this near Kin Kin in southeast Queensland, has destroyed habitat.
- 12:00AM December 30, 2017
Environment Editor
Sydney
There’s a tree change taking place on the frontline of Australian conservation. Images of the Great Barrier Reef and tales of bleaching and troubled waters are fading. Increasingly they are being replaced by pictures of koalas in distress. WWF Australia has been adopting out koalas for Christmas. Fifteen dollars a month buys bandages and medicines for injured animals, $30 a month will help plant a corridor of trees, and $50 will help take the fight to government on land clearing.
“Koalas are essential to the Australian identity,” WWF conservation science manager Martin Taylor says.
Koalas provide a rich canvas on which to explore bigger issues around land clearing and how humans share their space with animals. Governments can talk a big game on protections but often fail to deliver. Conservation laws with big intentions can create perverse outcomes and result in unintended consequences.
A key question is how best to protect abundant species that face critical issues in some areas but not in others.
Bad news for koalas can be good news for fundraising, but could it be true that the much-loved tree-marsupial is hurtling towards extinction?
Sceptics such as Vic Jurskis have accused lobby groups of making an icon out of what he considers to be a forest pest. The ecological historian argues that koalas are intrinsically rare animals — and sparse populations a marker of healthy forests — but environment groups and historical records disagree.
Millions of koalas were killed, skinned and exported for waterproof gloves and hats at the beginning of the 20th century. Ironically, it was then US secretary of commerce Herbert Hoover who banned the US import of millions of koala pelts each year in 1927.
Koala numbers did recover but urbanisation, disease, climate change and loss of habitat have numbers mostly in steep decline.
In areas where numbers are booming — Victoria and South Australia — there is argument over whether populations are sustainable and whether they should even be counted because they are introduced rather than endemic.
Elsewhere, urban development has clearly trumped koala protections. From 2009 to 2014, about 10,000 koalas were admitted to four emergency shelters in southeast Queensland, out of an estimated local population of fewer than 20,000 animals. WWF says the injuries were mainly caused by dog attack and car strikes. The region has a special koala ambulance to deal with the carnage.
Of those admitted for treatment, rehabilitation was largely unsuccessful, with only 2 per cent of koalas admitted for fractures from car strikes rehabilitated and released. The rest died or had to be put down.
NSW Chief Scientist Mary O’Kane admitted in a report in December last year examining the decline in koala numbers that “it may not be possible to ensure that all koala populations continue to persist in all locations”.
For conservation groups, koalas bring native animal protection directly to the household. “Koala campaigns hit a nerve because there are thousands of people who say they used to see koalas in their back yard all the time but now they are gone,” Wilderness Society national campaign director Lyndon Schneiders says.
But a snapshot of koala population health nationally presents a mixed picture. They are listed as vulnerable in Queensland, NSW and the ACT under the Commonwealth Environment Protection and Biodiversity Conservation Act. They also are listed as vulnerable on the International Union for the Conservation of Nature’s Red List of Threatened Species.
Abundance estimates for koalas nationally are highly contested. The NSW Chief Scientist’s report last year said Australia had about 330,000 koalas, with an estimated 36,000 in NSW. Australians for Animals founder Sue Arnold describes these figures as “highly questionable”. Arnold successfully lobbied for koalas to be listed as threatened under the US Endangered Species Act. She cites a 2015 Commonwealth Scientific Committee estimate that put the total population of koalas in Australia at about 85,000 animals.
Oisin Sweeney, senior ecologist at the National Parks Association of NSW, says he has no reason to doubt research showing almost all koala populations in NSW, Queensland and the ACT are in decline — many sharply so.
“In NSW we have seen alarming declines in almost all populations,” says Sweeney, “including 50 per cent declines in a 20-year period on the north coast.” There have been “major crashes of up to 90 per cent in the Pilliga (n the northwest plains of NSW) and southeast Queensland”.
A Queensland Environment Department report last year showed a decline in densities of about 80 per cent in the Koala Coast area, south of Brisbane, and 54 per cent in Pine Rivers (north of Brisbane in the Moreton Bay region) between 1996 and 2014, despite protection measures.
Rather than a slowing in the rate of decline, there was some evidence to suggest the rate of decline had accelerated, the report said.
On simple analysis, it’s a different story in Victoria and South Australia. Sweeney says koala populations have been introduced in Victoria and South Australia beyond their natural range.
“These populations have on occasion grown to the extent that they have decimated their own food sources. This can be typical of an introduced species,” Sweeney says.
Ecological consultant David Paull says that while some koala populations in Victoria and South Australia are growing sharply, others are in trouble. Much depends on whether a population has been introduced to an area or is endemic, he says.
A ranger handfeeds a koala to prevent its dehydration in hot weather. Picture: Wesley Monts
Populations of unique genetic stock associated with a particular area are for the most part in decline, while most introduced populations in Victoria and South Australia seem to be enjoying a phase of population growth.
“Like any introduced pest,” says Paull, “it is able to do well for a while in its new environment, as the trees may not have the natural defences that would otherwise limit palatability and population growth.”
Paull argues that introduced populations should be excluded from any threatened status, while indigenous populations should be included. Such a change would be significant and raises questions about the adequacy of national conservation laws.
Frank Carrick, a koala study program chief investigator at the University of Queensland, says a fundamental flaw of the federal Environment Protection and Biodiversity Conservation Act is that a species has to be in diabolical trouble across its entire range before the protection of the act is engaged. He says in this respect, the US Endangered Species Act has a better structure. “Specifically, in the case of koalas, one size definitely does not fit all,” he says.
A national koalas recovery plan, as required under the federal vulnerable listing in 2012, was set to be finalised three years later but was delayed by former environment minister Greg Hunt until June next year.
Of course not everyone believes koalas have a problem. A controversial new paper by Jurskis, published in the CSIRO journal Wildlife Research, claims there are more koalas today than at the time of European settlement.
Jurskis argues that a sign of a healthy eucalyptus forest is when koalas are found in sparse numbers, roaming large areas of isolated bushland. He says early settlers didn’t see any koalas and the first recordings were in 1798.
“The reasons they (koalas) are in large numbers is we are not managing the bush properly,” he says. Jurskis wrote in Quadrant online last year that koalas “became the poster animal for greenies and empire-building bureaucrats only after they became pests”.
“Regardless of ecological realities, it suits the activists’ cause to depict them as in danger and requiring salvation,” he wrote.
But Jurskis’s critics say it is difficult to reconcile his analysis with the historical records of culls. Research by the Australian Koala Foundation shows at least eight million koalas were killed for the fur trade, with their pelts shipped to London, the US and Canada between 1888 and 1927.
The foundation says that by 1912, koalas had been hunted to functional extinction in South Australia. By the 1920s, they were reduced to a few hundred individuals in NSW and 1000 in Victoria. In 1927 a final but highly controversial Black August hunt in Queensland killed more than 800,000 koalas in a single month.
For Paull, these numbers are sufficient to demolish Jurskis’s argument. Exports of two million skins a year represent more than 20 times present Australian total koala population estimates.
“The truth is koalas have never fully recovered from this period of intense culling and habitat loss,” he says. “It took over 30 years (in the 60s) before people started noticing koalas about in their rural neighbourhoods. It took another 20 years for koalas to become common in some areas, such as the Pilliga forest, where it is thought to have had a population of about 10,000 in the 1980s and 1990s.
“Prior to culling and widespread habitat loss, the population size in NSW could have been in the region of two million animals at any one time.” According to Paull, the only increases in populations since the cull period have been localised and modest. And many of these are declining.
Sweeney says Jurskis seems to have placed considerable confidence in observations that may be unreliable.
“It’s hard to see koalas in the bush, even where they are in high numbers, so settlers not seeing many is not surprising,” he says. “It seems incredible that within a century the European population could have altered the entire eastern part of Australia to the extent that koala populations increased from a few thousand to millions.
“The dual assertion that population declines are desirable because they are a correction from previous highs and that habitat loss is no problem is a major departure from conservation biology and from the research published on koalas. We know that since European settlement huge areas of koala habitat have been cleared and fragmented, and therefore population declines are no surprise.”
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