Mountain pygmy possums, which feed on bogong moths (Agrotis infusa) face worse threat of endangerment as their main food source is practically depleted.
The drastic decline in bogong moth numbers has left pygmy possums (Burramys parvus) starving and unable to feed their young. Recent routine checks in the Australian alpine showed dead litters in the pouches of the females.
Approximately 2 billion moths migrate from the grasslands of New South Wales and Queensland to approximately 1,000 kilometers (621 miles). However, a survey of 50 known sites of bogong moth caves in Victoria and Canberra revealed that these insects are gone.
"Last summer numbers were atrocious. It was not just really bad, it was the worst I had ever seen. This year we found just six moths. Last week we went back and there were none," ecologist Dr. Ken Green said, referring to a survey done in the Snowy Mountains of New South Wales.
Scientists believe that climate change and recent droughts affected the animals' survival mechanisms.
"Climate change across the vast migratory route of A. infusa is likely to further affect survival and availability for consumption by B. parvus," reported a study published in the journal Wildlife Research.
Alpine regions are most vulnerable to the risks of climate change. Droughts, severe bushfires, and the presence of feral cats and foxes are threats to mountain pygmy possums.
In 2011, scientists started a genetic rescue program in an attempt to increase the population of mountain pygmy possums. Healthy male mountain pygmy possums from Mt. Hotham were introduced to a female group in Mt. Buller.
These two groups have lost contact for over 20,000 years. This led to inbreeding that caused the lack of genetic variation among them.
Lead author Dr. Andrew Weeks from the University of Melbourne said the offspring from the genetic rescue were bigger than those born outside the program.
As of October 2017, the population of interbred mountain pygmy possums reached 200. The study confirmed that genetic rescue is successful in conserving isolated or threatened species.