The study led by Dr. Frederik Saltré from Sydney Technological University (UTS) and the Australian Museum revealed that the koala population in the Mount Lofty Ranges area of South Australia has reached 10% of the total koala population across Australia.
If no intervention is made, the koala population in the region is expected to increase by 17% to 25% over the next 25 years. Excessive population density is causing the rapid depletion of eucalyptus forests, the koalas' primary food source, through over-browsing.
Dr. Saltré noted that if the current trend continues, the next few decades could see mass koala deaths and widespread starvation.
As koalas are iconic animals in Australia, traditional methods such as culling (mass killing) or relocation are not seen as ethically or practically appropriate. Instead, scientists propose a proactive and humane solution:
It has been calculated that sterilizing about 22% of adult female koalas in the region each year could stabilize the population. The focus is recommended on the "hot spots" with the densest population instead of the entire region. The total cost of this 25-year management plan is estimated to be around 34 million dollars.
This "abundance" in South Australia is actually a side effect of a conservation success. In the 1920s, koalas faced extinction and were placed on islands and parks in the region. This population, free from diseases like Chlamydia that devastated the population on the east coasts, reproduced unexpectedly quickly due to suitable environmental conditions.
