Potorous tridactylus is a rabbit-sized rat-kangaroo with an elongated muzzle. The length of its head and body is approximately 300-400 mm, while its tail is about 150-260 mm long. Its pelage is straight, soft, and loose with a grey or a light chestnut brown coloration of its upper parts, a grayish or whitish underside, and often a white tipped tail. The median claws of its manus (fore foot) - well adapted for scratching and digging.
Potoroos have a down-curving, semiprehensile tail used for carrying bundles of nesting materials and it also has well-developed canines and bunodont molars. Potoroos have enlarged hind feet and powerful hind limbs which bestow them with adept hopping abilities.
The spread of foxes and feral cats throughout Australia has continued to reduce potaroo numbers at an alarming rate over the past 20 years in every habitat around Australia.
The aim of the Southern Ark project is to eliminate (as far as is possible) the introduced Red Fox (Vulpes vulpes) from an area of one million hectares of forested public land in Far East Gippsland, Victoria. The reason that this bold initiative is being undertaken is to significantly improve and reinvigorate the biodiversity of Far East Gippsland, and in particular to improve the conservation status of a range of endangered native mammals, ground-nesting shorebirds and reptiles. These species include the Long-nosed Potoroo, the Long-footed Potoroo, the Southern Brown Bandicoot, the Spotted-tailed Quoll, the Little Tern, the Hooded Plover and the Diamond Python.
The Southern Ark project is unique in Australia in a number of ways. Firstly, the project is operating across a very large area of land, and it is easily the largest area of public land in eastern Australia where foxes are controlled for biodiversity purposes. Secondly, while comparable large-scale fox control programs exist in Western Australia, the Southern Ark project is the only one in which baits are buried deep within constructed and maintained bait stations. This approach specifically targets foxes and successfully precludes poison baits being found and eaten by native non-target species. The Western Australian programs distribute baits from aircraft. Thirdly, within the area included as part of the Southern Ark project the ecosystems are essentially intact. Included in the Southern Ark program and they also support a full suite of predators, which includes dingoes, quolls, goannas, pythons, three species of large forest owl, and numerous diurnal birds of prey. This makes East Gippsland unique.
The eventual aim of the Southern Ark project is to have a substantial natural recovery of a wide range of rare and endangered species. This recovery of rare species will be complemented by the increase in species that are not regarded as being of particular conservation concern, such as the Ringtail and Brushtail Possums and the Long-nosed Bandicoot, and the re-establishment of a wide range of ecological processes that have deteriorated or ceased since the arrival of the Red Fox. Healthy forest and woodland ecosystems have large populations of bandicoots, potoroos and possums, turning over the soil in search of fungal truffles and invertebrates, improving soil aeration and water flow through the soil profile, helping to breakdown leaf litter and return nutrients to the soil, pollinating plants and spreading seeds. Their presence even influences fire behaviour, since they reduce the amount of fine fuels (leaf litter and other small vegetative material) on the forest floor. It is these fine fuels that carry and promote wildfires when they first start, and the reduction in the amount of fine fuels in the presence of robust populations of mammals makes it harder for fires to spread.
The only species that is currently extant in East Gippsland that it is anticipated that a captive breeding program may be undertaken to artificially increase the population following the implementation of the fox control program is the Diamond Python (Morelia spilotes spilotes). This species is confined to the far-east coast of the Southern Ark area of operation, and although it will appreciate the reduction in the fox population, the species potential for recovery is compromised by the fact that young pythons still fall prey to a wide range of predators, including goannas and other snakes.
Projects To Be Activated From This Funding
Long-nosed Potoroo, Potorous tridactylus
Project Summary: Long-nosed Potoroos have demonstrated a considerable population recovery in a number of experimental sites in Far East Gippsland as a result of nine years of continuous fox control. Tissue samples have been collected from most potoroos that have been captured, and a genetic analysis of these samples would be beneficial towards the understanding regarding the response of this species. For example, it would appear that although the surviving populations of potoroos have increased substantially in number, they appear to be occupying the same general areas that they were trapped when the program began. In other words, while there has been a population increase, there has not been an increase in site occupancy. At Cape Conran there are three discrete areas where potoroos have been captured. A genetic comparison of the individuals from each of these sites would determine if these populations, which are only a distance of several kilometres from each other, have remained isolated from each other despite intensive fox control. A genetic analysis will also confirm that the genetic makeup we have within the current potoroo population was present in the population when fox control commenced. This will confirm that what we are witnessing is a genuine increase in the resident population as a result of fox control, rather than an increase through immigration or because of an increase in the skills of those undertaking the trapping program. Given that we have collected tissue samples from almost all the potoroos captured, it is also hoped that we can determine maternity/paternity of the population, in order to generate a €śfamily tree€ť of the potoroo population.
The collection of tissue samples from almost all of the potoroos captured in a recovering population is unique; there are no other similar collections held anywhere in Australia. A genetic analysis of these samples will make an important contribution to the understanding as to how this endangered species responds to fox control, both temporally and spatially.
The Diamond Python
As discussed above, the Diamond Python is a species confined to Far East Gippsland in Victoria, and is regarded as endangered. It is known that adults, juveniles and eggs are all at risk from fox predation. Although adult pythons will benefit from the decline in fox numbers, it will take the python population some time to recover as juvenile pythons still fall prey to native predators such as goannas and other snakes.
This project is designed to assist the python population recover in Far East Gippsland. In the first stage (the stage in which funding is being sought for at this stage) a small number of captive breeding enclosures will be built on private land in East Gippsland, in an undisclosed location to ensure the safety of the snakes from theft. A number of adults will be captured from the wild and used as breeding animals. The captive population of pythons will be managed by staff and volunteers who have no contact with any other captive snakes or other wildlife to ensure that those snakes bred in captivity, when released, are not transferring any diseases back to the wild.
Orbost Spiny Crayfish, Euastacus diversus
The Orbost Spiny Crayfish is an endangered freshwater crayfish confined to a small area of East Gippsland north of Orbost. While appropriate management prescriptions are applied to those sites where the crayfish has been found, as part of the Flora & Fauna Guarantee Action Statement, no systematic survey has ever been carried out to identify the overall distribution of this species. While this project is not strictly part of the Southern Ark project, it does concern a species at risk from predation, in this case from the introduced Brown Trout.
The Southern Ark project has reached iconic status within Victoria, with fox control already implemented across 500,000 hectares of the total 900,000 hectares. While the Victorian State government provides funding for the baiting program and some broad-scale monitoring of the mammal response, funding for more detailed monitoring of the endangered species that have been driven to the point of extinction by foxes, but which have a fantastic capacity to recover, will be critical for the ongoing success of the project. Funding will also be required to monitor and assist the population recovery of native predators such as quolls and pythons, which have declined significantly after over 100 years of predation and competition by foxes.
Project Updates
http://forum.exetel.com.au/viewforum.php?f=323&sid=7921f33759cf99130d18660f0b5ebc49
Exetel has completed its financial commitments to this program and has not negotiated further financial support at this stage and therefore Exetel has ceased forwarding any customer donations as at May 31st 2010.. Any user who wishes to do so can make donations directly by visiting the sponsor’s site:
Detailed Species Information
http://en.wikipedia.org/wiki/Long-nosed_Potoroo
