MELBOURNE, Australia – You might think koalas are easy to find and count. You are tall. They are fluffy. They are mostly immobile as they tend to sleep around 20 hours a day.
“It’s the fact that they don’t move much that makes them difficult to spot,” said Desley Whisson, a wildlife ecologist at Deakin University in Victoria.
This makes the efforts of the Australian government to count the population of native marsupials and record where they live all the more daunting. In November, the government announced that it would allocate Australian $ 2 million (US $ 1.5 million) to fund an audit of the species, using new methods to do so.
When the count begins, heat seeking drones, acoustic surveys and detector dogs will be deployed. Individuals put on hiking boots and go into the bush to spot koalas. Many will also look for koala droppings.
The estimates of koala populations have historically varied widely. In 2016 there were over 300,000 koalas in Australia, according to estimates by scientists. In mid-2019, the Australian Koala Foundation estimated fewer than 80,000 remained in the country and said the number could be as low as 43,000. Concern and confusion about the number of koalas heightened during the devastating bushfires in Australia last year, leading to news articles that the animals were “functionally extinct”. But scientists have questioned the accuracy of this narrative.
A study commissioned by the World Wildlife Fund estimated that over 61,000 koalas were killed, injured or displaced in the forest fires last summer.
Even before the bushfires decimated koala populations, there were growing fears that the animals were in trouble. Scientists and conservation groups say habitat loss from deforestation is sending more koalas into urban areas – and occasionally people’s Christmas trees – where they could be flattened by cars and attacked by dogs. According to experts, koalas are also more prone to deadly diseases when they are under stress.
The last national census in 2012 only asked scientists to estimate numbers in specific regions, which resulted in a number of approximations, such as: B. 33,000 to 153,000 for a state.
“With all the focus on koalas, scientists tell us that there is a serious lack of data on where the population is actually located, how they are and how they can best recover after the devastating bush fires,” said Federal Environment Minister Sussan Ley in a statement at the time of the announcement.
The traditional way of counting koalas was to simply let people see how many they could spot. But when the marsupials stand high up in trees, stand still, and are covered by a canopy, they’re easy to miss with the naked eye, said Dr. Whisson. The number can vary greatly from person to person and depending on the conditions, so this method can produce a figure of 20 to 80 percent of the actual population of a site.
“For me personally, I see more koalas in the morning than in the afternoon,” she said. “In the afternoon you might get a little tired, your eyes might be a little tired, and you want to go home so you can speed it up a little.”
Since this is Australia, venturing out in the bush to count koalas likely means repelling snakes or various crawfish that are biting, making it difficult to focus.
“All sorts of things can distract you from what you are looking for and change the chances of you seeing a koala,” said Dr. Whisson.
So the scientists decided to use some other methods. Koala droppings – small brown pellets – found at the base of trees can determine whether they live in an area. Sniffer dogs can locate both koalas and their droppings. Male koalas roar during the breeding season, so scientists can leave recording devices in place to determine if koalas are nearby.
Koalas in remote or hard-to-reach locations can be counted with heat-seeking drones, but only in colder weather, as the animals’ fur provides a lot of insulation and they don’t give off much heat.
When all of these methods are used together and well, a count can be achieved with a margin of error as low as 10 percent, said Dr. Whisson.
A spokeswoman for Ms. Ley, the environment minister, said a national workshop of koala experts will be held next year to find out how best to do the census. “The audit will take a few months from there, depending on the extent of the problems identified and the strategies identified,” added the spokesman.
Dr. Whisson stressed that Australian officials cannot wait for the results of the audit to address the population decline issue. There is already ample data to show that koala numbers are falling in parts of the country, she said.
“If it takes a few years to get the census, the numbers will keep going down during that time,” she warned.
In fact, 23 conservation groups last week in an open letter entitled “Koalas Need More Than A Census,” demanded that the government do more to protect habitats. “Koala habitat deterioration has increased under your government and is ongoing,” said the letter to the environment minister. “Koalas can’t wait for a national census to reveal their numbers. You are now up to date. “
Rebecca Keeble, Regional Director for Oceania at the International Animal Welfare Fund, said, “Counting koalas is like counting the deck chairs on the Titanic as they sink.”
Some conservation groups are already taking matters into their own hands.
The World Wildlife Fund has the ambitious goal of doubling the koala population in Eastern Australia by using drones to drop tens of thousands of eucalyptus tree seeds to regenerate land devastated by bushfires (koalas eat eucalyptus leaves and use the trees for protection) and to create a fund to encourage landowners To create koala havens.