Ski victim: As few as 1,800 mountain pygmy possums remain - the species has experienced the most rapid loss of genetic diversity ever recorded for a mammal.
Credit: University of Melbourne
SYDNEY: Australia's only marsupial that hibernates under a blanket of snow has been pushed towards extinction by the development of ski resorts.
A new study reveals that the endangered mountain pygmy possum (Burramys parvus) has been threatened by resort development at Mount Buller, in the state of Victoria, and not bushfires or climate change as previously suspected.
The study, conducted by researchers from the University of Melbourne and La Trobe University, also in Melbourne, details the most rapid loss of genetic diversity ever documented in a mammal. It is published in the British journal Biology Letters.
Rapid decline
"Pygmy possums at Mount Buller have been in rapid decline in the last few years. Their genetic diversity has plummeted by more than two thirds over the last 10 years and this has been caused by habitat loss due to ski resort development," said geneticist and co-author Andrew Weeks.
The mountain pygmy-possum is restricted to alpine habitats of mainland Australia at Mount Buller and the nearby Bogong High Plains and also Mount Kosciusko in the state of New South Wales. In 2003 a large portion of the endangered animal's habitat was burnt by a rare bush fire, which was further exacerbated by ski resort development.
Boulder fields are the primary habitat of the possum but are also the ideal location for ski field development. The reduced habitat, introduced predators and other factors mean there are less than 1,800 adults and numbers are declining.
The study focussed on a range of populations in the Bogong High Plains that were affected by the 2003 fires and also two populations at Mount Buller; one where resort activities have disturbed or eliminated 80 per cent of the possum's habitat and another which has not been developed, but consists of less suitable habitat.
"Sensitive development"
The researchers took hair samples from numerous possums in each population and used DNA analysis to assess their genetic variation. They found that the site with the ski resort had a reduced population size and greatly reduced genetic variety. However, the fire-affected populations and those in poor habitat areas showed no loss of genetic variation and population numbers had not declined since previous studies.
"We have shown that levels of genetic variation in possum populations were unaffected by the 2003 fires' but there was a rapid loss of genetic variation following resort expansion at Mount Buller. The most immediate threats to the mountain pygmy-possums existence is human developments, not natural catastrophes or climate change," said Weeks.
The results show that resort developments need to proceed in a sensitive manner that preserves possum habitats intact, added co-author Paul Mitrovski. "Individuals from other populations will need to be introduced to prevent inbreeding and increase their genetic variation," he said.
with the University of Melbourne
