A Recovery Plan for the Great Desert Skink (Egernia kintorei) 2001-2011
Prepared by Steve McAlpin
On behalf of the Arid Lands Environment Centre, February 2001
- A Recovery Plan for the Great Desert Skink (Egernia kintorei) 2001-2011 (PDF - 233 KB) | (RTF - 1.9 MB)
The Great Desert Skink (Egernia kintorei) is a large burrowing lizard restricted to sandplain and gravelly habitats in the western deserts region of central Australia. Listed nationally as vulnerable, the Great Desert Skink has a scattered distribution across its range, and is known to have disappeared from former habitats, particularly in the Gibson Desert and Great Sandy Desert regions.
All currently known populations are on Aboriginal lands, and there is little coordinated management currently occurring for this species. A national Recovery Team for Tjakura (Great Desert Skink) was set up in 1999 to identify management priorities and to coordinate the national recovery effort.
The main threats to the ongoing survival of the Great Desert Skink appear to be inappropriate fire regimes and, to a lesser extent, exotic predator pressure. This Recovery Plan identifies a number of actions aimed at improving the conservation status of the Great Desert Skink. For logistical reasons, on-ground recovery actions are focussed in three key management areas: at Uluru-Kata Tjuta National Park, on Ngaanyatjarra Lands in the vicinity of Warburton Community, and on Aboriginal Land Trust lands in the Tanami Desert in the vicinity of Sangsters Bore.
Recovery actions detailed within this document are focussed on improving our understanding of current distribution, ecology, management needs and conservation status of the species. On-ground recovery actions are directed at implementing fire management (specifically reinstating patch burning regimes) around key populations, and undertaking predator control work in areas where the impact of fox and cat predation on Great Desert Skink populations is shown to be unsustainable.
The Recovery Team will annually review progress toward objectives detailed in this Plan, and results of these reviews and any changes to the Recovery Plan made as a result of new information or trends shown in monitoring programs will be made available to all stakeholders and groups or individuals with an interest in the recovery of the Great Desert Skink.
The Great Desert Skink (Egernia kintorei : Scincidae) is listed as vulnerable under the Commonwealth Environment Protection and Biodiversity Conservation Act 1999 (EPBC Act).
A Great Desert Skink Recovery Team was formed in March 1999 to coordinate national recovery actions in South Australia, the Northern Territory and Western Australia. The team is made up of representatives from the following bodies and agencies - Arid Lands Environment Centre, Uluru-Kata Tjuta National Park; Threatened Species Network NT, Central Land Council, Parks and Wildlife Commission NT; Alice Springs Desert Park; Ngaanyatjarra Council; Department of Conservation and Land Management, South Australian Museum; Anangu-Pitjantjatjara Council Land Management; and Department of Environment and Heritage SA.
This Recovery Plan has been prepared and written by Steve McAlpin for the Arid Lands Environment Centre with the assistance of the Recovery Team and a management team of Dr. Colleen O'Malley (TSN) and Dr. Craig James (CSIRO).
Knowledge of current distribution derives largely from consultations with Aboriginal people living in western desert regions, plus the few scientific records from survey or monitoring work in the region during the past 20 years. Most museum specimens of Egernia kintorei were collected by exploration parties or museum workers in the late 19th or early 20th century. Extant populations have recently been found at several sites where there had not been any previous records. However, many former localities appear to be currently uninhabited by the Great Desert Skink. Key populations have been documented in the course of this project and recommendations are made for their regional management.
The Great Desert Skink has historically occurred over a vast area (Fig. 1), from the northern Great Sandy Desert south to the south-eastern Great Victoria Desert, and from the central-west of Western Australia, near Wiluna, east to the eastern Tanami Desert in the Northern Territory. This area - over 20% of the landmass of continental Australia - is referred to as the western deserts region. The area is extremely remote from large population centres. Access for survey or research is difficult or impossible due to lack of roads. The tenure of much of this land is either Aboriginal Freehold or Leasehold Trust Land.
The Great Desert Skink is a large burrowing skink that grows to about 440mm total length and weighs up to 350g. The tail is slightly longer than the head and body and in good seasons becomes swollen at the base where fat is stored. The dorsal surface ranges from a bright orange-brown colour, similar to the desert sand, through to dull brown or light grey in some northern specimens. The ventral surface of adults ranges from a brilliant lemon-yellow in southern specimens to cream or grey in northern specimens. Adult males tend to have blue-grey flanks while females and juveniles may have either plain brownish flanks or vertically barred with orange and cream. Males attain greater body weight than females and have a broader head. New-born juveniles measure 70-80mm snout to vent length and weigh about 9-13g.
The Great Desert Skink constructs large burrow systems to a depth of over 1m and 10m in diameter. The burrow may start as a simple single tunnel with one entrance. New tunnels are added progressively and over a period of two summers a complex with 5-10 entrances and a network of connected tunnels five or six metres across may develop. A burrow system that is inhabited for many years may become very large. On the surface the burrow system of the Great Desert Skink is identifiable by at least one large external latrine. Scats are deposited in the latrine by the occupants of the burrow system and a large number of scats may accumulate over an area of one to three square metres.
Burrows of other animal species are also sometimes taken over, adapted and enlarged. The burrows of the Mulgara (Dasycercus cristicauda), Spinifex Hopping Mouse (Notomys alexis), Night Skink (Egernia striata), and Sand Goanna (Varanus gouldii) have been recorded as being appropriated and adapted by Great Desert Skinks (McAlpin 1997). Conversely, Mulgara, Dunnarts (Sminthopsis sp)and Ningaui (Ninguai ridei) have also been recorded on using the burrows systems of the Great Desert Skink, and the occupancy of a single burrow may transfer from one species to another (McAlpin 1997, 1998).
Despite the seemingly large effort that goes into constructing a burrow system, occupancy appears to be dynamic, with some lizards moving between burrow systems (McAlpin 1998) and some burrows eventually becoming deserted. The reasons for this dynamism are not understood but may relate to the search for a mate, formation of new pair bonds, mortality, or predation pressure. A large burrow is generally occupied by an adult pair and juveniles from the current and previous year. Up to 10 individuals may inhabit one burrow system. Females give birth to from one to seven live young in early summer (S. McAlpin, D. Pearson unpublished data).
Great Desert Skinks are omnivorous, eating a wide range of invertebrates (principally termites) and also any vertebrates small enough to be swallowed. During good seasons they consume leaves, flowers and fruits from several species of plants including Bush Tomato (Solanum spp.) fruits, Parakeelya (Calandrinia spp.) leaves and Paper Daisy (Leuchochrysum stipitatum.) flowers (McAlpin 1997). Young Great Desert Skinks grow rapidly and during good seasons reach sexual maturity in their second year. Maximum size is reached in the third year and young males are unlikely to participate in breeding until they are fully grown and living in a well established burrow system. Great Desert Skinks are may live to a considerable age. Other species in the genus Egernia have been recorded to live for over 20 years in captivity (Swan 1990).
Lizards disperse from their natal burrow in their second year. Young males attempt to establish a burrow system and attract a mate. Many of these lizards are apparently unsuccessful as most small, newly established burrows fail (McAlpin 1999). The reasons for this are unknown, but a small, simple burrow would offer less protection from predators than large, burrow complexes with many tunnels. It is highly likely that predation pressure is greatest on this age-class of lizards. Ref?
In Central Australia during the past 100 years numerous species, mostly mammals, in the critical weight range (CWR: 30-1500g) have either become totally extinct or have been reduced to relict populations (Burbidge and McKenzie 1989). This catastrophic species loss is thought to be due to the combined pressures of exotic predators, competing feral herbivores, and the cessation of traditional burning practices.
The Great Desert Skink is a key species of some of the extensive habitats in the western deserts. These habitats supported a diverse mammal fauna until the early to mid 20th century, when extinctions began to take place. Great Desert Skinks are near the peak of the food chain for these habitats. Their large, elaborate burrow systems are utilised by many other species including the 'Vulnerable' Mulgara. The importance of their burrows in terms of ecosystem function is likely to be considerable.
Habitat management through regular, patch burning is seen as the most beneficial method of aiding the recovery of the Great Desert Skink. This system of land management had been in place for many thousands of years prior to European settlement. By burning while hunting and traversing their country Aboriginal people created a mosaic of different fire-age habitats on a relatively fine scale. Patches of hundreds or thousands of hectares were burnt at one time. Ref? This practice prevented the possibility of the huge wildfires that now characterise the fire regime in the western deserts region. When a fine-scale mosaic is maintained a large fire simply could not carry into areas of regenerating vegetation. These small patches would be usually 'fire-proof' for a period of up to 15-20 years in southern desert areas. In northern areas, where more rain falls, this was a shorter period of 5-10 years. Ref. Matched numbers with those given on P7 Patch burning may have taken place as soon as an area would carry a fire. The area may also have been further broken-up by lighting a fire that was unable to carry over all of a previous burn.
The cessation of this intensive, low intensity burning for a period of time as short as 20 years is enough to allow the build up of large fuel loads so that vast wildfires are able to burn through country. Once all the vegetation is mature a fire is able to burn unchecked. In an area north of Warburton where this intensive burning practice has been more or less continuous during the past century the Great Desert Skink is still relatively common. Aboriginal people travel along a road between two communities and the area is subject to constant hunting and small-scale patch burning. The country for several kilometres either side of the road is managed in this fashion over a distance of more than 200km. The landscape is a patchwork of different size and aged areas of regenerating spinifex shrubland. The patches range in size from 50ha to a few thousand hectares.
Despite the pressure of hunting, Great Desert Skinks have persisted and appear to be flourishing in this area. By contrast, the adjacent country around the Gibson Desert Nature Reserve is no longer managed in this fashion. Within this large area few access roads exists, visitation by Aboriginal people is infrequent, and little burning work is done. As a consequence fires tend to burn through hundreds of thousands of hectares at a time, creating extensive patches of even-aged vegetation. No Great Desert Skinks were located during a recent four day transect search in this region. Aboriginal people who had not visited this area for many years expected to see the Great Desert Skink 'all through this rirra country' and were surprised at the apparent decline of the species.
The creation of a mosaic of habitat patches of varying ages may also benefit other species. Recovery actions undertaken for the Great Desert Skink are also likely to benefit several other species listed under the EPBC Act - the 'Vulnerable' Mulgara, the 'Vulnerable' Bilby (Macrotis lagotis), the 'Endangered' Northern Marsupial Mole (Notoryctes caurinus) and the 'Endangered' Southern Marsupial Mole (Notoryctes typhlops). The Great Desert Skink is often found in association with the Mulgara and Marsupial Mole at Uluru (McAlpin pers. obs.). In the Tanami Desert the Bilby is often found at the same locality as the Great Desert Skink (Masters et al 1997). Reintroducing traditional patch-burning regimes across the western deserts region is likely to benefit biodiversity generally, by maintaining plant diversity and creating patchy landscapes at a scale appropriate to animals that depend on this plant diversity and structural complexity of habitat.
The Great Desert Skink is well known to senior Aboriginal people throughout the western deserts region, and is known as Tjakura (Pitjantjatjarra/Yankunytjatjara) or Warrarna (Warlpiri). Many old people grew up hunting this species and celebrating it through story and ceremony. It is an important component of Tjukurpa (or Law) in the western deserts, and sites for the Great Desert Skink are spread across the region. The skink retains an important status for many traditional people who continue to hunt and gather on their lands. Central to this is the facility to teach following generations about the range of traditional activities undertaken, and also of all the species present within country and of their significance.
Several Aboriginal communities will be affected by the Great Desert Skink Recovery Plan. It is considered that benefit to these communities will be derived through opportunities to participate in recovery actions. A concomitant increase in the biodiversity of these regions should also benefit the communities by providing a higher standard of living in relation to both traditional hunting and cultural activities.
The precise distribution of the Great Desert Skink is likely to remain vague. Thousands of patches of potentially suitable habitat exist within an area of more than 1 500 000 sq km in the western deserts region of the Northern Territory, Western Australia and South Australia. Most of this area is remote with no roads or tracks, and much potential habitat remains unsurveyed.
Historically the Great Desert Skink has been recorded from widely scattered localities across the western deserts region (Fig. 1). Prior to 1980, museum specimens have been collected in Western Australia from the vicinity of Broome - given as Roebuck Bay; the northern end of the Canning Stock Route; at Kathleen Valley between Wiluna and Leinster; from north west of Warburton adjacent to the Rawlinson Range; and from south of Warburton at Skipper Knob. The type specimen was collected in 1891 from the northern Great Victoria Desert, about 150km SE of Warburton. The only historical record from South Australia is of a single museum specimen collected in 1934 at Pundi Rockhole, between the Everard Ranges and Emu Junction. In the Northern Territory specimens were collected prior to 1980 from Mt Liebig; Angus Downs Station; from near Yeundumu; and in the Tanami Desert from the vicinity of The Granites gold mine. Recent records have added several additional localities in both Western Australia and the Northern Territory, and one from South Australia (Fig. 2).
Currently the strongholds for the Great Desert Skink appear to be the Tanami Desert, Uluru and an area of the Gibson Desert north of Warburton. An extensive sandplain of several hundred square kilometres to the east of Kiwirrkura also contains a significant population (Fig. 2). This population is currently 'managed' by traditional methods. In the context of what is known about the current overall distribution of populations the Kiwirrkura sandplain population is also regarded as significant. There may also be a significant population within the Rudall River National Park and recommendations for survey and monitoring in this area are made later in this document.
The Great Desert Skink first became known to wildlife authorities and scientists at Uluru in 1980. This is the only currently confirmed population from a protected Reserve or National Park. The population size inside Uluru-Kata Tjuta National Park is about 500 individuals (McAlpin 1998). This population spans the boundaries of the Park and continues into the Yulara resort land and also onto the Yulara airport land.
A specimen of E. kintorei was recorded at Watarru in north-western South Australia in 1998, the first for that state in 64 years (Daniel 1999.). In 1997 a new locality north of Warburton in Western Australia produced the first museum specimen from that state in 33 years (Pearson pers. comm.). There are numerous small populations in the Tanami Desert. These populations appear to be very mobile, presumably in response to the more frequent fire regime. Because of the higher and more dependable rainfall in the Tanami Desert region, plant growth and consequent fire susceptibility in this northern locality is greater in comparison to southern localities that receive significantly less rainfall. There have been two episodes of extremely extensive wildfires in the Tanami within the past 10 years - in 1994 and again in 2000. How these fires affected the current populations of Great Desert Skinks is unknown.
Aboriginal people living in remote communities have led the Recovery Team to previously undocumented populations. Undoubtedly other populations will be documented following further fieldwork. Nevertheless numerous populations that were known to Aboriginal people have apparently become locally extinct. A series of interviews was conducted with senior Anangu living at Uluru, who had grown up in widely scattered areas. Most stated that the skinks were no longer found at sites they had known them from in their youth. Senior Traditional Owners at Watarru (Anangu-Pitjantjatjara Lands) also recalled the skink as common and frequently eaten back in the 1950's and 1960's (Daniel 1999). During a recent survey in the Gibson Desert Nature Reserve, WA several Traditional Owners showed surprise and alarm that no Great Desert Skink burrows were located at all. People were confident at the start of the journey that Great Desert Skinks occurred 'all across the rirra country' that we drove through. Senior men living at Yuendumu recently reported two former localities near Yuendumu where Great Desert Skink were once found but no longer occur.
There are several historic localities that have not produced specimens since the original records. Some of these localities, such as Mt. Liebig, Yeundumu and Roebuck Bay are not isolated and could be expected to produce specimens if the species still existed in the region. Other historic localities such as Kathleen Valley (now Wanjarri National Park) have been the focus of general fauna surveys but no specimens have been located. A recent broad-scale survey of the Little Sandy Desert failed to locate any specimens (Kendrick pers. com.). There are no historic records of Great Desert Skink for the Little Sandy Desert region, though large areas of potentially suitable sandplain habitat exist.
Great Desert Skinks occupy a variety of habitat types within the western deserts region. They generally occur on hummock grass sandplains and some adjacent dunefield swales. In the Tanami Desert and parts of the Great Sandy Desert they also inhabit paleodrainage lines characterised by giant termite mounds and titree (Melaleuca spp.) shrubs. The recently discovered population in northern S.A. was located in an area of spinifex and Woollybutt Grass (Eragrostis spp.) with scattered mulga. Extensive areas of dunefields, rocky ranges and mulga woodlands occur through the western deserts and are considered unsuitable habitat. However the area of potentially suitable habitat within the region is tens of thousands of square kilometres.
Sandplain vegetated by spinifex and scattered shrubs seems to be the habitat type most widely used. These sandplains range in size from a few hundred hectares to tens of thousands of hectares. They are characterised by a dominant cover of spinifex grasses, usually Triodia basedowii, but also T. pungens and T. schinzii. Growing among the spinifex hummocks are scattered shrubs and occasional trees from the genera Acacia, Eremophila, Grevillea, Hakea, and occasionally Eucalyptus. Why some sandplains are currently occupied while others are not is unknown, but may relate to recent fire history. The swales of dunefields adjacent to sandplains may also be occupied by Great Desert Skinks. The vegetation in these adjacent swales is generally similar to the sandplain.
Large areas of the Gibson Desert are characterised by undulating low hills. This habitat is known locally as rirra. Some of the hilltops constitute rocky outcrops, usually of laterite. The surface of the hills and upper slopes are covered in laterite pebbles and small stones. The lower slopes and valleys have a more sandy surface. The soil under the laterite cover is a fine sand that also contains numerous laterite pieces. In mature areas of this habitat hard spinifex (Triodia basedowii) is the dominant plant and few other species are present. Sparsely scattered shrubs of Desert Fireweed (Rulingia loxophylla), Keraudrinia nephrosperma, Desert Raisins or Bush Tomatoes (Solanum spp.), Parakeelya (Calandrinia spp.), Rusty Sand-sage (Dicrastylis exsuccosa) and Black Wattle (Acacia pruinocarpa) and patches of mulga often occur on the hilltops. The lowest valleys may be lined with Acacia and Grevillea shrubs. In this country Great Desert Skinks inhabit the open areas on the hilltops and slopes. They appear to be absent from the heavily shrub-lined valleys.
During the course of survey work for this project several previously undocumented populations were recorded. A very extensive, scattered series of populations documented from the 'rirra' country between Warburton and Karilywara are 'managed' by traditional methods in which frequent, small scale, low intensity fires are lit while hunting for animals. These populations are scattered by the nature of the topography and habitats, whereby areas of currently inhabited or regenerating rirra are broken up by areas of dunefields or rocky hills that are unsuitable for Great Desert Skinks.
Data exists from two separate surveys that recorded the presence and absence of Great Desert Skinks from a wide range of habitat types. Fifteen of 190 sites surveyed at Uluru had Great Desert Skinks present (McAlpin 1997). In this study lizards were not found in mallee woodland, mulga woodland or areas burnt more than 25 years previously. The majority of burrows at Uluru are in habitat burnt within the past 15 years (McAlpin 2000). In a survey in the Tanami Desert Great Desert Skinks were present at seven of 165 sites. Four of these sites had been recently burnt. During the same survey Mulgara were recorded at 34 of the 165 sites, and Bilby at 41 of the 165 sites (Masters et al. 1998). Bilbies were present at six of the seven sites where Great Desert Skinks were recorded.
Great Desert Skinks appear to be well adapted to a patch-burning regime, whereby loose colonies of lizards are able to move into adjacent, recently burnt habitat when necessary. Under such a strategy they are never able to occupy all the sandplain habitat at any one time, as some portions will always be of an unsuitable fire age, usually too young. In areas that are intensively managed by traditional methods patches will be burnt as soon as they are able to carry a fire, and thus patches are highly unlikely to become too old to provide suitable habitat. Cessation of these traditional hunting and burning practices and consequent proliferation of large-scale wildfires greatly limits recolonisation by Great Desert Skinks. Instead of numerous small patches of varying fire age vegetation, vast areas become a single fire age that may be either too old, or too young for successful habitation. Wildfire cycles are tied to rainfall totals. In the driest parts of Great Desert Skink's range this inter-fire period is thought to be about 15-20 years, while in the northern part of its range rainfall is more reliable and annual totals are considerably higher. Spinifex growth is comparatively rapid and wildfires may occur every 5-10 years.
Great Desert Skinks generally occupy areas of habitat that have been burnt within the previous 3-15 years. In 1998 in Uluru-Kata Tjuta National Park 57% of active burrows were in habitat burnt greater than 15 years previously. In 2000 this had fallen to 36%, with another 36% of active burrows in habitat burnt less than 10 years previously (McAlpin 2000). The research there also suggests that recently burnt habitat provides a better opportunity for successful reproduction. The productivity of Great Desert Skink burrows (in terms of numbers of juveniles recorded) is greatest in the areas burnt within the past 10 years. Thirty eight percent of burrows in habitat burnt in 1976 produced juveniles, whereas 59% of the burrows in habitat burnt in 1991 produced juveniles (McAlpin 1999). This greater breeding success may relate to an overall increase in biodiversity and productivity in recently regenerating habitat.
Surviving a large-scale fire may be difficult or impossible for this species. During a hot wildfire virtually all vegetation is removed over a very large area. Most of the invertebrates and small vertebrates that live among the vegetation are also destroyed. While Great Desert Skinks are able to survive the initial effects of the fire down in their burrow, the subsequent lack of cover and food resources may mean the lizards are unable to persist. A large fire may create distances that are too great for lizards to be able to cross to successfully colonise a new area.
The population at Uluru has been studied since 1996. Initially the basic biology and ecology was documented (McAlpin 1997). All burrows that could be located in the Park were then mapped and a monitoring program was established (McAlpin 1998). One hundred and two active burrows were originally mapped in 1998. In 2000 only 50 of these burrows remain active, though there are still about the same total number of active burrows in the Park (McAlpin 2000). The population is extremely dynamic, and lizards appear to be moving out of habitat that is 15-25 years old and establishing burrows in more recently burnt areas. At Uluru sub-populations are found as clustered sets of active burrows, while large areas of similar, adjacent habitat remain unoccupied. The populations at Kiwirrkura and Warburton appear less clustered and more evenly spread across larger areas. This may be as a result of hunting pressure and a more intricate fire history in these latter areas.
Following the breeding season at Uluru in 1998, about 45% of the population were adults, 40% were juveniles and 15% were subadults. This relatively low percentage of subadults suggests that juvenile mortality is high, though this has not been specifically investigated or documented.
The population at Uluru is the only one to have been studied scientifically, and much remains to be learnt about population dynamics in response to post-fire plant succession and resource availability. No study has been undertaken on the dynamic between feral predators and the Great Desert Skink. Overall, most populations of E. kintorei appear to be small, scattered and usually isolated. Vast areas of potentially suitable habitat appear to be totally unoccupied or are at extremely low population densities. Historically, when patch burning was undertaken across all of the potential habitat, there may have been genetic flow between seemingly separated areas of occupation. This now appears highly unlikely.
The total population size of the Great Desert Skink is difficult to estimate with any certainty. There are undoubtedly undetected populations in remote areas of the western deserts region. The population within Uluru-Kata Tjuta National Park is about 500, while total numbers in the Tanami are unlikely to be greater than 2000. The total population in Western Australia may exceed 5000. In South Australia no other Great Desert Skinks have been located since the rediscovery of two active burrows in 1998.
There is considerable anecdotal evidence of a general decline in the overall population of the Great Desert Skink, and it has disappeared from many sites during the past 50 years (McAlpin 1997). The skink is well known to Aboriginal people throughout the western desert region of N.T., W.A. and S.A. Numerous informants reported that in areas where they had grown up, Great Desert Skinks had once been common but had since vanished or had greatly reduced in numbers (McAlpin 1997).
The cessation of traditional land management practices over most of the western deserts region has created a new fire regime. Vast areas remain unburnt for many years. When a fire eventually burns in these unmanaged areas, either by lightning strike or through human intervention, it is likely to be a very hot, extensive fire that creates a huge swath of burnt country with few patches of unburnt habitat within it. Small animal populations at the edge of such a fire may be able to survive, but the chance of finding a suitable patch of unburnt habitat for most animals within the fire zone is greatly diminished. Over time such a fire regime is likely to eliminate most populations until only a few fragmented, small populations persist. The arrival of two efficient feral predators - the cat and fox - adds to the pressure on these isolated populations. This appears to be what has occurred to the Great Desert Skink.
Both the fox and cat have been identified as predators of Great Desert Skinks. Cats prey on the skinks, particularly juveniles, by sitting near a burrow entrance and waiting to pounce on a lizard when it emerges (S. McAlpin pers. obs.). Foxes catch skinks after dark when the lizards are actively foraging out from their burrows (I. Noble pers. com.). The extent of this predation is unknown as is the overall threat to the species or to individual populations. Rabbits have been recorded moving in to one active burrow system of the Great Desert Skink, causing the lizards to abandon the burrow system (McAlpin 1997). Mulgara are known to prey on Great Desert Skinks (S. McAlpin pers. comm.), possibly concentrating on juvenile or hibernating lizards. The impact of this predation pressure on Great Desert Skink populations is currently poorly understood.
Populations at Yulara (near Uluru) are currently under threat from increasing tourism development. Tourism infrastructure at Yulara and within Uluru-Kata Tjuta National Park has occasionally been inadvertently sited close to active Great Desert Skink burrows, resulting in burrow abandonment, or mortality of lizards on roads. A very significant population of Great Desert Skinks occurs in the Yulara borefields area, where the water supply for Yulara township is sourced. There are some concerns that planned increases in the volume of artesian water harvested may impact on the biologically diverse borefield's flora and fauna, including Great Desert Skink populations. A spinifex harvesting program conducted as part of a fire management program around tourism infrastructure at Yulara is also thought to pose a threat to resident populations of Great Desert Skinks in this area.
The only populations of the Great Desert Skink that appear to be secure are found in areas that currently have intensive fire management occurring. One of these populations is in Uluru-Kata Tjuta National Park where patch burning has been recommenced to enhance biodiversity conservation as well as to mitigate the threat of extensive wildfire. In other populations intensive fire management has been as a result of continuous traditional hunting practices. Optimal patch-burn size for the Great Desert Skink is as yet unknown. Current adaptive management practices at Uluru, combined with continued population monitoring should enable a patch burning prescription to be developed for possible application in other parts of the western deserts region.
The actions listed in this Recovery Plan do not commit the identified stakeholders, organisations or agencies to any works or to allocation of funds for works, but, rather, act as a guide for planning management for Great Desert Skinks in a coordinated way across the species' range.
The timeframe for this Recovery Plan is ten years. The main reason for opting for a ten-year management period relates to the characteristic variability of arid environments in which large seasonally-related fluctuations in populations are normal, such that a ten-year monitoring cycle is necessary to show actual trends in populations unrelated to this climatic variability. Other reasons for this extended management timeframe relate to the remote nature, and resourcing needs of the region in which Great Desert Skinks live. Major constraints to implementation of this Plan are the high costs associated with work in remote regions, and the absence of any existing regional threatened species management programs across much of the Aboriginal Lands in which Great Desert Skink populations survive.
Management actions listed in the Recovery Plan focus on collecting further basic data on which to assess current conservation status, population trends and threatening processes. Other actions are focussed on key known populations and represent adaptive management approaches based on the best currently available data. In the course of implementation of the Plan, these actions may need to change to take into consideration new information or newly emerging threats.
The Recovery Plan focuses management actions around three key populations of Great Desert Skink:
- Uluru-Kata Tjuta National Park
- on Ngaanyatjarra Lands in the Gibson Desert
- on Aboriginal Lands in the Tanami Desert in the vicinity of Sangsters Bore
The reasons for focussing the Plan this way were largely logistical. It is not considered feasible to plan effective management over the entire western deserts region given the vast area and remoteness from community living areas in many instances. Recovery of this species (as with many other threatened desert animals) is likely to rely on ongoing management both of fire and predators, and there fore requires ongoing commitment from communities living in the vicinity of populations. Lastly, the difficulty in resourcing recovery work on extensive Aboriginal lands required the choice of focus areas.
- At Uluru an ongoing Great Desert Skink monitoring program was established in 1996. Cooperative management programs involve both Anangu Rangers and Park staff. Fire management by patch burning is being conducted and a recent review and Fire Management Plan has been undertaken. A Vertebrate Pest Management Strategy for the Park is currently being formulated.
- On Ngaanyatjarra Lands in the Gibson Desert an Indigenous Protected Area is currently being set up as a cooperative program between Ngaanyatjarra Council and the WA Department of Conservation and Land Management. Land management - including patch burning, predator control and threatened species monitoring - is currently being undertaken by Ngaanyatjarra Council staff and Aboriginal community members.
- At Sangsters Bore there has been on-going threatened species monitoring work carried out by Parks and Wildlife Commission staff with assistance from Aboriginal people. Sangsters Bore area is an important biological refuge area and until the early 1990s supported the last known population of Mala (Lagorchestes hisutus). Bilby, Mulgara and Great Desert Skinks are all known from the area. In 2000 a trial predator management project involving Aboriginal people was established in the Sangsters Bore area, and further funding is currently being sought by the Threatened Species Network to expand this project.
The major focus of the plan is on land management through the continuation and expansion of traditional patch burning practices. This approach will be combined with feral predator control, viewed as the second tier of threat to E. kintorei populations. For the success of this Plan Aboriginal co-management and involvement in recovery actions is critical. Several Aboriginal communities exist near Great Desert Skink populations and all currently known populations are on Aboriginal land. The bulk of knowledge on patch burning resides in these communities, and it is expected that much can be learnt by developing cooperative management projects. Increasing our understanding about the fire management needs of the Great Desert Skink is likely to benefit other threatened fauna of spinifex desert ecosystems (Mulgara, Bilby, and Mala), and if active landscape-scale fire management can be implemented across these regions to recreate the patchy habitats Aboriginal people formerly managed, there are likely to be significant general biodiversity benefits.
- To maintain or improve the conservation status of the Great Desert Skink over the next ten years
- To change fire and feral animal management in three focus areas of the western deserts to benefit populations of the Great Desert Skink
|Specific Objective||Performance criteria||Actions||Stakeholders||Approximate cost|
|1.1 To collect sufficient data to determine the extent of the current population range, and assess causal factors in recent declines or local extinctions in particular locations, and to determine critical habitat.||1.1.1 Reduce the gaps in the knowledge of current range and produce a distribution map by 2004.||126.96.36.199 Identification factsheet and record datasheet produced and disseminated to Aboriginal communities, Aboriginal service agencies, wildlife management agencies, ecotourism operators, mining industry and 4WD networks by 2002.||Recovery Team and agencies and organisations represented.||$1,500|
|188.8.131.52 Records database established in 2001 and incoming information used to compile current distribution map by 2004.||Recovery Team and agencies and organisations represented.||$250|
|184.108.40.206 Fauna survey of Rudall River National Park completed by 2003, and management recommendations made for any Great Desert Skink populations identified.||CALM, KLC and Mardu Community.||$5,800|
|220.127.116.11 Further survey work on Anangu-Pitjantjatjara Lands in SA completed by 2002.||AP Land Management, DEH||$2,750|
|1.1.2 Causes of recent population loss from at least two areas established by 2006.||18.104.22.168 Identify two sites from which the Great Desert Skink has disappeared in the last 20 years (based on Traditional Owner knowledge), and collect data on vegetation condition, fire history and predator loads. Compare this with data from sites with current populations, and determine likely causes for local extinctions. Use this data to update Recovery Plan actions.||Recovery Team and agencies and organisations represented, various Aboriginal community members, NT Bushfires Council.||$15,000|
|1.1.3 Critical habitat determined and mapped by 2006||22.214.171.124 Use records database, comparative locality data and monitoring data to determine critical habitat and produce critical habitat map by 2006.||Recovery Team and agencies and organisations represented.||$5,000|
|1.2 To manage by 2010 at least two key populations to maintain or improve population levels as measured against an initial baseline figure derived from monitoring data collected over five seasons to account for seasonal population fluctuations.||1.2.1 Overall, an increasing trend in numbers of active burrows recorded in Uluru-Kata Tjuta National Park over the period 2001 to 2010.||126.96.36.199 Continue to map active and abandoned burrow systems within UKTNP on an annual basis, and record information on spinifex structure, fire history and predator sign along permanent transects.||Parks Australia in collaboration with Office of Joint Management and Anangu Rangers.||$2,500 p/a|
|188.8.131.52 Continue patch burning program around burrow sites at UKTNP, and monitor impact on burrow occupancy. Undertake further research to determine links between spinifex and plant community age or structure and frequency of burrow occupation.||Parks Australia in collaboration with Office of Joint Management and Anangu Rangers.||$3,300 p/a|
|184.108.40.206 Monitor predator impact around active burrows using track surveys and predator scat analysis. If necessary undertake predator control work in accordance with UKTNP Vertebrate Pest Management Strategy. In winter months collect Mulgara scats within monitoring sites and analyse these for possible predation on hibernating lizards.||Parks Australia in collaboration with Office of Joint Management and Anangu Rangers.||$2,560 p/a|
|220.127.116.11 Produce educational materials (by 2001) for Ayres Rock Resort Corporation and other organisations with infrastructure adjacent to Great Desert Skink populations to encourage adoption of conservation management measures and to discourage further development in these sensitive areas.||Recovery Team||$1,200|
|18.104.22.168 Encourage further research into likely biodiversity impacts of further increases in amount of water drawn from the Yulara borefields.||Recovery Team||N/A|
|1.2.2 Baseline data on at least two key populations on Ngaanyatjarra Lands and in the Tanami Desert collected by 2007. Overall population trends at these sites shown to increase over a ten year period.||22.214.171.124 Establish monitoring sites in at least two locations on Ngaanyatjarra Lands and in the Tanami Desert by 2002. Collect annual burrow activity data at these sites, and use five consecutive years' data to estimate baseline population levels by 2007.||Ngaanyatjarra Council, CALM, TSN, CLC, PWCNT.||$12,800|
|126.96.36.199 (Also see 188.8.131.52) Undertake regular patch burning and predator control work at monitoring sites on Ngaanyatjarra Lands and Tanami Desert.||Ngaanyatjarra Council, CALM, TSN, CLC, PWCNT.||$7,800 p/a|
|184.108.40.206 Analyse stomach contents of feral predators during predator control work, and collect and analyse predator scats in vicinity of Great Desert Skink populations.||Ngaanyatjarra Council, CALM, TSN, CLC, PWCNT.||$2,500|
|1.3 To improve community knowledge of the Great Desert Skink and increase community involvement in recovery management.||1.3.1 Increased involvement of Aboriginal people in management programs for the Great Desert Skink||220.127.116.11 Ensure that all projects focusing on Great Desert Skink management have strong involvement of Aboriginal people. Include funding for wages for Aboriginal participants in monitoring, fire management and predator control work.||Recovery Team||N/A|
|18.104.22.168 Undertake training in contemporary survey and monitoring techniques and predator control with Anangu at UKTNP, From communities in the Tanami Desert and on Ngaanyatjarra Lands by 2003.||Parks Australia, OJM, Anangu Rangers, Ngaanyatjarra Council, CALM, TSN, CLC, PWCNT.||$10,500|
|1.3.2 Increase in reported sightings by ecotourism operators and 4WDers by 2005.||22.214.171.124 Establish a records database (see 126.96.36.199 & 188.8.131.52) for the Great Desert Skink and advertise its existence among Aboriginal Communities, ecotourism operators, the 4WD community, mining companies and agencies working in the western deserts region in 2002.||Recovery Team||See previous costing.|
|1.4 To secure ongoing funding for implementing recovery actions identified in this Recovery Plan.||1.4.1 Funding secured for at least 70% of the Recovery actions identified in the Plan.||184.108.40.206 Seek sponsorship from mining companies for Great Desert Skink recovery work in the Gibson, Great Sandy Desert and Tanami Desert.||Recovery Team||N/A|
|220.127.116.11 Seek funding from philanthropic trusts for collaborative recovery projects with Aboriginal communities.||Recovery Team||N/A|
|2.1 To determine the best fire regime that leads to sustained or increased populations of Great Desert Skink over a 10 year timeframe||2.1.1 Improved understanding of scale, frequency, timing and patterning of fires to benefit Great Desert Skinks by 2010.||18.104.22.168 Create GIS database for data on fire history, spinifex structure and burrow occupancy, and use this to record monitoring data from the 3 focal areas.||Recovery Team, Bushfires Council NT, CSIRO.||$2,750|
|22.214.171.124 Correlate fire history data from areas within UKTNP and parts of the Tanami Desert with presence/absence data for Great Desert Skinks. Produce a predictive map of potential Great Desert Skink habitat based on fire patchiness. Continue to refine map with survey and monitoring data collected over the next decade.||Recovery Team, Bushfires Council NT, CSIRO, Post-graduate student.||$5,875|
|2.1.2 Increase in the patchiness of habitat around monitoring sites at UKTNP and on Ngaanyatjarra Lands by 2008||126.96.36.199 Maintain patch burning program at UKTNP, with up to 5% of suitable habitat burnt each year, and not less than 10% burnt over any 3 year period. Record all fire data on GIS database.||Parks Australia, OJM and Anangu Rangers.||$4,500 p/a|
|188.8.131.52 Establish a fire management program at monitoring sites on Ngaanyatjarra Lands by 2003. Annually record data on timing and extent of fires and enter this data with burrow occupancy data onto GIS database.||Ngaanyatjarra Council and CALM.||$6,500 p/a|
|2.1.3 Development of fire prescriptions for management of Great Desert Skink populations, and incorporation of these into fire management plans at UKTNP, within the IPA areas on Ngaanyatjarra lands by 2010.||184.108.40.206 Based on 10 years of data from UKTNP and Ngaanyatjarra Lands, develop fire management prescriptions for Great Desert Skink populations and ensure that this information is used in planning management programs||Recovery Team, Bushfires Council, Parks Australia, OJM, Ngaanyatjarra Council.||N/A|
|2.2 To reduce number, impact and extent of destructive wildfires in Great Desert Skink focus areas over the next decade.||2.2.1 A reduction in the frequency and size of wildfires on a regional scale in the vicinity of UKTNP, the Tanami and Ngaanyatjarra Lands focus areas by 2010.||220.127.116.11 Form working group of stakeholders, scientific experts and Bushfires authorities to prioritise areas for fire management and to plan strategic control burns.||Recovery Team, CSIRO, Bushfires Council NT, CLC, CALM.||$4,500|
|18.104.22.168 Involve Aboriginal communities in implementing strategic control burns outside of UKTNP, in parts of the Tanami Desert and Ngaanyatjarra Lands IPA.||Recovery Team, Ngaanyatjarra Council, CALM, CLC, Bushfires Council NT.||$7,800|
|2.3 To implement feral predator control programs that lead to sustained reductions in feral predator loads around two focus populations of Great Desert Skinks over the next 10 years.||2.3.1 Predator levels around monitoring sites at UKTNP and Ngaanyatjarra Lands maintained at levels where impact on Great Desert Skink populations appears to be minimal (as determined by numbers of juveniles recorded each season).||22.214.171.124 Establish permanent predator track transects in the vicinity of the study sites at UKTNP and on Ngaanyatjarra Lands and record predator numbers regularly in course of monitoring work.||Parks Australia, OJM, and Anangu Rangers, Ngaanyatjarra Council, CALM.||$2,500 p/a|
|126.96.36.199 Undertake regular predator control work around monitoring sites using both traditional tracking and hunting, and contemporary baiting programs where appropriate.||Parks Australia, OJM and Anangu Rangers, Ngaanyatjarra Council, CALM||$4,200|
At this stage there are insufficient data on the distribution of the Great Desert Skink and on the conservation status of individual populations to recommend against certain activities in the vicinity of specific known populations. These guidelines therefore apply generally to the species and to all locations which support Great Desert Skink populations. As further survey data becomes available this Plan will be updated to include management recommendations for particular populations considered to be key to the ongoing survival of the species across its distribution range.
The following actions may negatively impact on population viability and recovery of the Great Desert Skink:
- Siting of roads, tracks or built infrastructure within 5km of known populations of the Great Desert Skink;
- Mining activities sited within 5 km of active burrows of the Great Desert Skink;
- Spinifex harvest activities or other vegetation clearance carried out within 1km of active burrows of the Great Desert Skink.
The progress of recovery actions listed in this Plan will be monitored and evaluated on an annual basis by Recovery Team members and reported to relevant funding agencies, project sponsors, Aboriginal Land Councils and wildlife management agencies. To assess progress Recovery Team members will review the activities of individual projects and evaluate outcomes against actions and performance criteria listed in the Plan. If deficiencies are identified, or if the timeframes set for particular actions are not being met, the Recovery Team will reassess the importance of the particular action, and if deemed to be a priority, will work with the appropriate stakeholder group to ensure completion of the project. Where additional funding is identified as a constraint to completing an action the Recovery Team will assist the stakeholder group in accessing funds from sponsors, philanthropic groups or Commonwealth or state funding agencies.
Biological data on fire management and fire regime impacts on burrow occupancy, and data on predator abundance and impacts will be complied by the Recovery Team from individual projects on an annual basis, and included in the annual progress report.
The Recovery Team will use data from the sightings database and additional survey data from agencies, ecological consultants and Aboriginal organisations to update the distribution map for the Great Desert Skink on a biennial basis. This map will be made available to Aboriginal organisations and communities, wildlife management agencies and mining companies and tourism ventures with operations in the region.
The Recovery Team will evaluate community involvement and awareness on a biennial basis by assessing the numbers of Aboriginal people participating in recovery work, and reviewing the numbers of reported sightings of Great Desert Skink made by the general public. The Recovery Team will actively encourage the production of plain-language, pictorial-style 'big books' for each Aboriginal Community participating in recovery work. These books are a very useful record of community involvement and encourage ownership of projects, as well as being useful education tools for younger people.
The Recovery Team will be responsible for reviewing the progress of this Recovery Plan in 2006, and again in 2011. These reports will be made available to all relevant stakeholders, sponsors and funding agencies and to Environment Australia.
- Arid Lands Environment Centre
- AP Land Management
- Anangu Pitjantjatjara Council Land Management Section
- Department of Conservation and Land Management
- Central Land Council
- Commonwealth Scientific and Industrial Research Organisation
- Department of Environment and Heritage SA
- Environment Australia
- EPBC Act
- Environment Protection and Biodiversity Conservation Act
- Kimberley Land Council
- Office of Joint Management (Uluru-Kata Tjuta NP)
- Parks and Wildlife Commission NT
- Threatened Species Network
- Uluru-Kata Tjuta National Park
- World Wide Fund for Natur
- Steve McAlpin - Arid Lands Environment Centre (RT Chairperson)
- Peter Copley - DEH SA
- Matt Daniel - Anangu-Pitjanjatjarra Council Land Management
- Glenn Edwards - PWCNT
- Greg Fyfe - Alice Springs Desert Park
- Mark Hutchinson - SA Museum
- Ro McFarlane - Ngaanyatjarra Council (from 9/00)
- Sean Moran - Central Land Council
- Keith Noble - Ngaanyatjarra Council (until 9/00)
- Colleen O'Malley - Threatened Species Network
- David Pearson - CALM
- Sam Rando - Uluru-Kata Tjuta National Park
- Arthur Robertson - Ngaanyatjarra Council
A Recovery Plan for the Great Desert Skink (Egernia kintorei) 2001-2011
Funding to prepare this Recovery Plan was received by the Arid Lands Environment Centre from the Threatened Species Network Community Grants Program (a joint initiative of the Worldwide Fund for Nature Australia and the Natural Heritage Trust).
The contributions of the following Traditional Owners from Uluru-Kata Tjuta, Anangu-Pitjantjatjara Lands, Ngaanyatjarra Lands and the Tanami Desert were crucial to the understanding of current and past distribution and ecology of the great desert skink: Norman Tjakalyiri, Imanatura Richards, Millie Okai, Daisy Walkabout, Jimmy Muntjatji, Johnny Tjalyiri, Simon Brumby and Jacob Wongin (Uluru-Kata Tjuta); Mary Pan, Illawanti Ken, Vera Pan, Brenton Ken, Ian Gibson and Yanyi Ken (Anangu-Pitjantjatjara Lands); Arthur Robertson, Pulpuru Davies, Janey Ward, Gregory Fox, Nowali Campbell, and Nancy Carnegie (Ngaanyatjarra Lands); Charlie Walabi, Charlie Ward, Patrick Jungarrayi, Ray James Jangala, and Donna James Nungarrayi (Kiwirrkura), Yuendemu George Tjapanangka and Willie Tjungarrayi (Kintore), Thomas Rice Jangala and Shorty Jangala (Yuendumu).
Besides the author's input into this document, significant input was received from Colleen O'Malley (TSN) and Craig James (CSIRO). Thanks also to Brigitta Wimmer (Regional Wildlife, EA), and to Dave Pearson (CALM) and Peter Copley (DEH SA) and other members of the Tjakura (Great Desert Skink) Recovery Team (see membership list p 23) for comments on earlier drafts. Ann Hardy (National Reserve System Section, EA), Rod Nowrojee (ERIN, EA), Jake Gillen (EA) and Jim Longworth (CSIRO) generously provided GIS data and created the maps for this document.
© Arid Lands Environment Centre Inc. 2001
Copies of this document can be obtained from:
Arid Lands Environment Centre
PO Box 2796
Alice Springs NT 0871
Photo: Great Desert Skink outside its burrow at Uluru-Kata Tjuta National Park. Source: Steve McAlpin