AUSTRALIAN WILDLIFE SOCIETY Funds a new strategy to save the mountain pygmy-possum from extinction
The mountain pygmy-possum boulder fields and dense alpine rock Hibernating mountain pygmy-possums (Burramys parvus) is a small nocturnal crevices of southern Victoria and reduce their body temperatures from marsupial, endemic to the alpine Kosciuszko National Park in New the normal active temperature of 36°C regions of Australia, and has been South Wales. It survives winter by to approximately 2°C during torpor selected as the Society’s 2020 wildlife hibernating for up to seven months bouts. To hibernate successfully, of the year. and is dependent on the insulation mountain pygmy-possums require provided by snow, and its primary temperatures between 1.5°C and 2.5°C. Through sponsorship from Kinder food source, for its survival. Therefore, Hibernation can last between five to (Ferrero Australia), the Society is changes in climate pose a considerable seven months. The mountain pygmy- playing a key role in the preservation risk to this species. of the mountain pygmy-possum by funding a program to help save this Hibernation is a seasonal response Above: The mountain pygmy-possum is a species from a changing climate and to changes in climate and food small, mouse-sized nocturnal marsupial of possible extinction. availability. Hibernating mammals Australia found in dense alpine rock screes endure prolonged intervals of torpor, and boulder fields, mainly southern Victoria The mountain pygmy-possum has during which the body temperature, and around Mount Kosciuszko in Kosciuszko adapted to live exclusively in alpine metabolism, and other metabolic National Park in New South Wales at elevations habitat. It is found in highly elevated functions are significantly reduced. from 1,300 to 2,230 metres.
Australian Wildlife Vol 2 - Autumn 2020 17 possum prepares for hibernation by doubling its bodyweight before winter begins. The mountain pygmy-possum will eat as much as it can to store enough energy to last through the duration of its dormant period.
The survival of the mountain pygmy- possum depends not only on its immediate environment but also on the regional migratory patterns of its major food source, the bogong moth (Agrotis infusa). Each spring, the bogong moth leaves the heat of their breeding grounds in southern Queensland and north-western New South Wales to fly more than 1000 kilometres until they reach the Australian Alps in south Victoria and Kosciuszko National Park, in summer, where they congregate in huge numbers. Once there, they switch their bodies into a dormant state, not unlike hibernation (in summer this dormancy is called aestivation). The peaks of the boulder fields and rock crevices are used as their aestivation The mountain pygmy-possum is mainly grey-brown with paler grey/brown to cream underneath. Its sites. A few months later, the moths fur is fine but very dense keeping the animal warm in sometimes freezing temperatures. It has a migrate back north to breed as their darker ring of fur around its eyes, rounded ears and a long tail. larvae cannot tolerate cold conditions.
The mountain pygmy-possum is the largest of Australia’s five species of pygmy-possum, yet it only weighs 45 grams and could easily fit in the palm of your hand.
18 Australian Wildlife Vol 2 - Autumn 2020 Hibernation, the insulation provided endangered on the International Union endangered mountain pygmy- by snow and the migratory patterns of for Conservation of Nature’s Red List possums at warmer, lowland rainforest the bogong moth, play a key role in the of Threatened Species. Its threatened conditions and lower altitude of mountain pygmy-possum’s survival. Dr status is one of the reasons why the 1000 metres. This strategy has been Hayley Bates, from the University of New Australian Wildlife Society selected the implemented to assist the mountain South Wales, stresses that if there isn’t mountain pygmy-possum as its 2020 pygmy-possum to adapt, shift and enough snowfall or snow melts early due wildlife of the year. acclimatise to a more temperate to a warming event, as climate modelling climate, like its ancestral habitat. This predicts, the cold air will penetrate the To combat the effects of climate strategy will provide the mountain alpine rock crevices and adversely affect change, scientists from the University pygmy-possums with the opportunity the survival of the mountain pygmy- of New South Wales have established to adapt to a warmer temperature, possum. Temperatures below 0.6°C a breeding program at Secret Creek providing it with the chance for survival will wake a mountain pygmy-possum Sanctuary, based on evidence provided and preventing it from becoming a from its hibernation and put it at risk of by the fossil record of its ancestors. potential victim of climate change. shivering to death. Furthermore, due to The Australian Wildlife Society is the migratory patterns of its food source, helping to fund this program to help While there are many unanswered if woken early its food source will not save the mountain pygmy-possum questions and there is still so much be present, and therefore the mountain from extinction. The fossil records more to learn about this species, the pygmy-possum is also at risk of starving show that the prime habitat of the breeding program at Secret Creek to death. If the mountain pygmy-possum mountain pygmy-possum’s ancestors Sanctuary provides the opportunity experiences two consecutive winters of was rainforest environments. to study the animal and its breeding decreased snowfall, warming climate behaviours at a warmer temperature. and non-present key food source, then As Australia dried out, some animals If the program is a success and it can the species could collapse and go extinct. adapted, however some, including be demonstrated that the mountain As a result, in New South Wales, the the ancestors of the pygmy-possum, pygmy-possum can establish a foothold mountain pygmy-possum is listed as were so connected to the rainforest in a more temperate environment, an Endangered Species on Schedule 1 environment that they followed the UNSW Professor Mike Archer predicts of the Threatened Species Conservation environmental shift eastward. The that other threatened animals could be Act 1995 and is classified as critically program aims to breed the critically preserved using the same strategy.
The mountain pygmy-possum is the only marsupial in the world known to store food and hibernate for extended periods.
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