Mountain pygmy possum (thing)

The Mountain Pygmy Possum (Burramys parvus) is a small marsupial found only in the high mountain country of New South Wales and Victoria in Australia. It is an unusual creature from several points of view.

Burramys was originally only known as a partial fossil - dated back to the Pleistocene age. It was first found as a fossil in 1894 in the Wombeyan Caves in New South Wales by a Dr. Broom. Broom thought it was a miniature kangaroo, and named it from the Aboriginal word Burra burra - meaning rocky ground, and the Latin parvus and mys - meaning small mouse. More bones were later found at that site which showed it to be a pygmy possum. The other fossil site was found around 1960 by Norman Wakefield and Bob Warneke, near the Murrindal River in eastern Victoria.

The fossil fragment that distinguished Burramys was the lower jaw bone - found at both sites. The jaw had a huge, jagged premolar tooth projecting from half way along its length. No other pygmy possum has such a tooth - leading to Broom's original classification as a kangaroo species.

Burramys parvus remained a fossil mystery for many years. While Wakefield hoped to complete a skeleton - he had been unable to do so, and hence very little was known about the creature.

In 1966, a group of skiers at Mount Hotham in Victoria adopted a small pygmy possum that lived in the ski hut. As it was different to the usual native rats that infested the place, a skier named Ken Shortman, a scientist, took the possum home as a pet for his daughter.

Curious as to the possum's species, Shortman took the animal to the Department of Fisheries and Wildlife in Melbourne. Unable to identify it, they kept the possum, and started contacting experts in the field of Australian wildlife. As one of the leading naturalists of his day, Norman Wakefield was telephoned. Inspecting the possum's lower jaw, he found the huge premolar tooth that is only found in Burramys parvus. Dr. David Ride, Director of the Western Australian Museum, had worked on the Burramys fossils years previously. He wrote:

"Burramys had come to life. The dream dreamed by every paleontologist had come true. The dry bones of the fossil had come together and were covered with sinews, flesh and skin."

While that first Burramys soon died, it was not long before others were discovered, and a captive breeding colony established.

Burramys is only found in high, cold alpine areas - their habitat ranges in elevation from 1400m to 2230m . A colony lives all year round on Mount Kosciuszko, the highest peak on the Australian mainland. Other colonies are found in the Victorian alpine areas. They are omnivorous - eating mainly insects, seeds, and fruits from the mountain plum-pine. They live on the most inhospitable parts of the mountain - exposed to the fierce westerly winds, in areas where snow often reaches three metres thick. They hibernate in winter, occasionally waking to feed on cached food stores.

Burramys parvus is still a threatened species. While fairly common in its restricted habitats, the habitats themselves are at risk. Damage by visitors, weeds, development of ski fields or the enhanced greenhouse effect could all cause the Burramys' habitat to decline. The present habitat of Burramys parvus is less than 10 square kilometres, and the present population is around 2600 adults. Other threats come from predation by introduced species, and factors that disturb hibernation, such as loud noises.

Burramys is a difficult species to breed. Taronga Zoo in Sydney has tried for some years to breed them, but with no success. The animals require a cold environment, and the budget has not yet stretched to a walk in refridgerator for the animals. The males are also unable to breed if carrying too much body fat - a problem for captive animals.

Various conservation strategies are underway to protect the Mountain Pygmy Possum. Development of ski fields is restricted in Burramys habitat areas, populations are regularly monitored, genetic research is being undertaken, and wildlife corridors created to improve population dynamics.

Since the bushfires that began in January 2003 through much of New South Wales and Victoria – a large portion of the habitat of Burramys parvus has been destroyed. When comparing maps of the area burnt with distribution maps of the species, the results are alarming. The main Victorian habitat areas of the possum have been burnt – and while patches of habitat may still remain, in most areas the fire did not follow the classic mosaic pattern that would allow these habitat patches to survive. All the areas in Victoria where Burramys has been recorded in the last 20 years are within the burned areas.

In New South Wales, the Kosciuszko National Park has been burned over about 75% of its area in the last spate of bushfires. While the peak of Mount Kosciuszko itself escaped – hopefully providing sufficient refuge for any Burramys that survived the blaze – it is too much to hope that many of the possums were not killed.

It is yet to be established what portion of the possum communities has survived. The impact on the populations could be severe indeed. The fires occurred only shortly after the birth season of the species (November-December) – meaning that many vulnerable juveniles were likely to be lost. The gender distribution of breeding adults is already skewed heavily towards the female – around 80%. This may well give the species a better chance of rapidly regaining their numbers – however, if too many males were killed, the species may be under dire threat through sheer inability to breed. In addition – the fact that the next breeding season is 8 or 9 months away means that the remnants of the population will have to survive until then in order to begin replenishing their numbers.

As information comes to hand I will update this node. For now, there is still hope for the species – sufficient habitat and individuals may well have survived to re-establish the populations. If not, there are still captive populations in existence, and if the wild population were to fall to drastic levels it is certain that the breeding of captive populations would be given more priority than it has had in the past.