Bushfires, housing divisions, vehicle crashes and wall attacks – all of which have hurt koalas – have been devastating in recent decades.
Researchers have found that a combination of environmental impacts and human disturbances on koala habitats, puts many parts of Australia at risk of extinction.
“In the last 10 years, we have seen a significant increase in koala rescue as there are more koalas in the open and on the ground,” said Edward Narayan, a senior professor of animal sciences at the University of Queensland.
That is not a good sign for the species that live in the trees. For their survival, koalas rely on eucalyptus trees, which they use for food but also to find shelter and breeding.
Narayan says koalas are in danger because in the long run, chronic stress is detrimental to their immune system.
“Humans have all these artificial resistance mechanisms to deal with stress, but with animals, the problem is that most small animals are good at hiding their fears,” Narayan said. “You can not tell whether an animal is sick or not unless it hurts.”
“We have also found that cases are on the rise, so more and more koalas have been found to have a high prevalence of cholera, which is one of the diseases that affect koalas,” Narayan told CNN. “As a result, many koalas really need to be improved, but unfortunately.”
Human effects on koalas
Human population growth has had an increasing negative impact on the koala population through multiple stressors, according to Narayan.
“One of the biggest factors is land clearance,” Narayan said. “What is happening is that koalas are facing more and more pressure outside the city. That housing corridor is more vulnerable … we can see these developmental bubbles affecting koalas.”
Narayan added that agriculture also played a role in the decline of koalas, as natural land was set aside for agricultural development. The study’s researchers argued that sustainable farming practices and nature conservation were critical to saving koalas.
WWF aims to double the koala figure
WWF says planting more trees is necessary after the bush season, when 7,000 trees were harvested and 3 billion animals were slaughtered.
“Unprecedented damage calls for an unprecedented response,” Dermot O’Gorman, WWF Australia Executive Director, said in a statement.
O’Gorman added that efforts to increase the number of koalas by 2050 will benefit many other species as well as boost the economy of communities in the region.
“WWF is excited to experiment with specialized drones, some of which can grow up to 40,000 seeds a day, to create corridors so that koalas and other wildlife can move across landscapes divided by fire and land clearing,” he said.
“The koalas add to the voice of the Australian environment,” he said, adding that their decline signifies a bigger crisis in the natural world. “The amount of damage that has been done to the planet – we can not hide from it.”
“Ultimately what will happen to this effect on nature is that we will build our own grave, in any way possible,” he said.