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Home , Golden bandicoot, Kimberley rock rat, King George River

Kimberley bouncing back

Better management of the wild north Kimberley—made by Ian Radford, possible by funding provided under the state government’s Carolyn Thomson-Dans, Kimberley Science and Conservation Strategy—is producing encouraging results, with populations of several Richard Fairman and threatened native species already bouncing back. Ed Hatherley he north Kimberley is one of The Kimberley mammal and bird species found in the T few relatively untouched large Kimberley, and more than 500 plant wild areas left in the world. Covering species. about 105,000 square kilometres of Mitchell Plateau is one of the most high-rainfall monsoonal tropics, it is a scenic and biologically important areas National Biodiversity Hotspot, with at of the state, with spectacular gorges and least 230 plant, 16 fish, 10 frog, 31 reptile, waterfalls, extensive fan palm forests on six mammal and two bird species found its lateritic top and small patches of nowhere else. Mammals endemic to the rainforest around its margins. Up to 50 region include the scaly-tailed possum mammal species, 220 bird species and (Wyulda squamicaudata), monjon Mitchell rivers. This vast, natural region 86 species of reptile and amphibian (Petrogale burbidgei) and Kimberley has a rich Aboriginal heritage, with may occur in the area. rock rat ( woodwardi). North Aboriginal people retaining strong Kimberley landscapes are famed links and responsibility for country. Critical situation for their enormous complexity and The dramatic islands and coastlines The far north Kimberley is among beauty. The region includes the entire are unique. The complexity of the the least disturbed environments in catchments of the Prince Regent and northern coast and islands is such that and, until quite recently, the 2,581 mapped islands between critical weight range (those Yampi Sound and the King Edward weighing between 35 grams and Above Golden-backed tree rat. River give rise to some 12,850 5.5 kilograms) were thought to be kilometres of coastline, although the secure in this region. However, it Right Scaly-tailed possum. Previous page straight-line distance between Yampi now appears that a number of native Photos – David Bettini Main Mitchell Falls in the Kimberley. Sound and the is mammals are declining in many parts Photo – David Bettini only about 400 kilometres. of northern Australia, including the Insets from left to right Kimberley rock Prince Regent National Park, rat, brush-tailed phascogale and monjon. north Kimberley. Evidence for these Photos – Jiri Lochman rugged sandstone and volcanic declines has come from comparing in the north. This is a particularly country at the core of the north historical records with current important conservation issue because Below . Kimberley, contains more than half the knowledge, large-scale monitoring the north Kimberley is the last mainland Photo – Kevin Coate/Sallyanne Cousans programs, documentation of Aboriginal refuge for many mammal species. Photography knowledge and targeted studies of While the reasons for mammal individual species. declines are complex, there is no doubt There have been major contractions that the Kimberley region is under in the range of a number of mammal increasing pressure. In 2009, cane toads species including the brush-tailed crossed the border (Conilurus penicillatus) and and continue to spread west into WA, the golden (Isoodon auratus). despite efforts from community groups This continues a trend of declining and government to halt their progress. mammal distributions and extinctions, Other feral animals, particularly feral particularly in the arid zone, ever since cattle, and changing fire regimes European settlement of Australia. are altering both the landscape and In the Northern Territory, there plant and composition and have been documented declines in diversity. Studies by Northern Territory the ranges of species such as the scientist John Woinarski revealed that released in June 2011 and provides a committed $21.5 million over five black-footed tree rat ( significant mammal declines in the chance to address this situation across years for this terrestrial conservation gouldii), common brushtail possum Northern Territory were linked with the region. program, with ongoing funding of $5.5 (Trichosurus vulpecula) and northern fire frequency; the most severe declines Threats to Kimberley biodiversity million a year. quoll (Dasyurus hallucatus), which have were associated with the most fires. occur across all land tenures including contracted northwards over a 20 to In other regions of Australia, feral cats parks, pastoral lands and Aboriginal Fire management 30-year period. Surveys by Department are implicated as one of the primary lands. The Kimberley Science and One of the most significant of Environment and Conservation causes of mammal declines (along with Conservation Strategy therefore has initiatives under the strategy addresses (DEC) scientist Tony Start and others foxes which are not present in the a tenure-blind approach. This means possibly the greatest threat to the in 2003–04 found that similar patterns tropics), though this is not yet proven that to adequately address threats, biodiversity of the region—extensive were evident in the Kimberley, with for tropical savannas. such as fire, feral animals and weeds, bushfires. Large and intense fires in the many animals contracting into the far cooperation is needed across property late dry season have caused changes northern coastal strip. At the local scale Conservation in action boundaries via partnerships between to vegetation structure such as the too, mammals appeared to be declining The state government’s bold DEC, traditional owners, pastoralists loss of large hollow-bearing trees, the in many areas. These findings led to vision for this region’s long-term and other key land managers such as removal of shrub layers, increased soil serious concerns that another major conservation—the Kimberley Science the Australian Wildlife Conservancy erosion and declines in native animal extinction event could be imminent and Conservation Strategy—was (AWC). The government has populations. Fires often rage across

34 Landscope Landscope 35 Left A DEC Aboriginal ranger lighting a back burn at a wildfire. Photo – DEC

Below left Northern quolls have re-established populations near Mitchell Falls. Photo – David Bettini

Bottom left A late dry season wildfire near the Mitchell Falls walk trail. Photo – Ed Hatherley/DEC

hundreds of thousands of hectares because, once started in the heat of the dry season, they are almost impossible to contain, particularly in the rugged parts of the region. Not only do these fires occur on a massive scale, they often occur in the same areas year after year, providing insufficient time for the plants and animals to recover. Above Golden bandicoot. Since 2008, DEC, in collaboration Photo – David Bettini This involves placing numerous small- since 2007, despite significant annual with traditional owners, the Kimberley trap quadrats (survey sites) across the trapping efforts, and were trapped for Land Council, Aboriginal ranger landscape to sample representative the first time at the Mitchell Falls groups, the Department of Fire and Cattle are known to have adverse habitats. Sampling is based on major ranger’s camp in 2012. Emergency Services, pastoralists, effects on mammal populations due habitat and vegetation differences, as The brush-tailed rabbit rat has the AWC and other partners, has to habitat degradation. Surveys by different mammal communities are suddenly become very abundant in developed and applied improved fire Sarah Legge of AWC on Mornington typically associated with different some areas. Up to 17 individuals were management strategies. Contemporary Station showed dramatic increases in habitats. So far, the results have been caught in 2011 and 2012 at Lone science is being integrated with both the numbers of individual animals extremely encouraging. Dingo, north of the main Mitchell traditional Aboriginal knowledge. and species richness after the AWC Plateau, whereas only one was caught Prescribed burns are being conducted removed cattle from the area. These Animals return here during Tony Start’s survey in 2003, in the late wet and early dry seasons to changes were most dramatic four years Northern quolls are still common which used more traps. This species has create a mosaic of burnt and unburnt after the removal of cattle and were and abundant in sandstone habitat in also appeared at sites near Surveyors areas. The resulting patchwork effect evident across all habitat types. the north Kimberley, for example on Pool where it had not been recorded from these prescribed burns reduces DEC initiated cattle-culling the Mitchell Plateau, in Prince Regent previously. the amount of fuel available and has operations on the Mitchell Plateau in National Park and in King Leopold Seasonal changes don’t seem to resulted in fewer large, intense and 2009, and increased the operations as Ranges Conservation Park. However, explain these differences on their own damaging fires later in the dry season. a result of the Kimberley Science and since 2008, with DEC’s changes in because there is no clear relationship For the region’s wildlife this means Conservation Strategy’s landscape-scale fire regimes, quolls have been found between rainfall and mammal numbers distances between patches of unburnt conservation initiative (see ‘Looking in areas south of the Mitchell Falls in the north Kimberley as there is habitat are reduced. after country’, LANDSCOPE, campground, where they were not in the desert. It appears brush-tailed This treatment has been applied to Autumn 2012). Together with changes initially captured in trapping studies. rabbit rats might respond dramatically large areas of the north Kimberley, and in fire regimes implemented under the These areas have historically been more to cattle removal, as Lone Dingo and funding available under the Kimberley initiative, these measures may already frequently burnt. However, quolls are Surveyors Pool are the areas where Science and Conservation Strategy be benefiting the mammals of the still much less common in the south cattle culling has been most effective. has enabled DEC to expand these Mitchell Plateau. (around the King Edward River area) These areas once held up to two beasts programs across almost 20 million and in non-rocky habitats. per square kilometre, whereas surveys hectares of land. It is also estimated that Are we making a difference? Golden-backed tree rats and culling records now show less than this vast prescribed burning program is DEC has the important task of (Mesembriomys macrurus) were rarely one beast per two square kilometres. significantly reducing the amount of monitoring areas that have been the captured on the Mitchell Plateau until Also apparently doing well and carbon released into the atmosphere focus of improved management under the 2011–2012 surveys, although they well represented in the 2011 and 2012 every year. the conservation initiative in the north were present in the area in the 2003 monitoring and evaluation surveys Kimberley. survey. However, the recent surveys are golden , Ningbing false Effects of cattle To determine how the mammals are showed they had reappeared at a antechinus (Pseudantechinus ningbing), Expansive feral animal and weed responding to the new fire and cattle number of sites where they formerly the Kimberley rock rat and other control projects are also underway as management regimes, they are using a occurred. They had also spread into including the pale field rat part of the Kimberley Science and monitoring method developed by John a number of sites in sandstone areas (Rattus tunneyi) and grassland melomys Conservation Strategy. Woinarski in the Northern Territory. where they had not been recorded (Melomys burtoni). Although the brush-

36 Landscope Landscope 37 Above Mitchell Plateau fan palms (Livistona eastonii) occur over much of the Mitchell Plateau itself. In 2007 and Mitchell Plateau. 1981–82. More research is needed in 2008, only three animals were caught the north Kimberley to determine the Below Monjon. over almost 1,000 trap nights (0.31 status of this giant . Photos – David Bettini per cent trap success). Since then, trap success has improved markedly to more What does it all mean? than five per cent (an animal in every It appears that concerted efforts to tailed phascogale (Phascogale tapoatafa) 20 traps) on the northern Mitchell better manage fire and feral animals was not trapped, there have been a Plateau. However, trap success is still (cattle in particular) by DEC and number of sightings of this species very low (two per cent) in more inland other organisations such as AWC are near the Mitchell Falls campgound areas closer to King Edward River. improving the status of threatened since 2007. It may be that alternative These areas are still often affected and other mammals in the Kimberley methods to monitor this species (such by fires lit off the Kalumburu Road, region. DEC’s monitoring and as nest boxes) will prove more effective despite the best efforts of DEC and evaluation found there was a very in determining its numbers. other agencies. strong relationship between mammal While native mammal populations abundance and diversity and fire Trends and concerns of the Kimberley appear to be bouncing frequency, with areas being burnt more Overall there are a number of back, there are some exceptions. than once every two years having far interesting findings in the mammal Although often recorded in surveys on fewer mammals. Sites in which the data from 2007 to now. There appears Theda Station, the rock ringtail possum fire frequency was less than one in five to have been a period of very low (Petropseudes dahli) was not recorded in years (such as parts of Prince Regent mammal abundance and diversity the Mitchell Plateau, King Leopold or National Park) have the highest rates of around 2007–08, followed by recovery Prince Regent areas in 2011–12. The mammal trap success. of populations. The 2007–08 season nabarlek (Petrogale concinna) or little However, there are still areas of high coincided with very high cattle rock-wallaby has not been confirmed cattle density and high fire frequency numbers, with cattle invading areas in the area, although people who sight (such as the King Edward River area) such as Mitchell Falls campground. this animal could easily confuse it where improvements need to occur. Fires were also very large and with the monjon, which is reasonably When patterns of fire frequency are widespread beyond the Mitchell Falls common. The huge black-footed tree mapped, it is clear that there are more campground area. rat, which grows to 800 grams, has not fires the further away the area is from A key habitat in which trapping been recorded at all during the surveys, the coast. These areas will be the focus of success has improved enormously since nor was it recorded in 2003. The last efforts under the Kimberley Science and 2007 is the tall forest on top of the recorded animals were captured in Conservation Strategy in coming years.

Ian Radford is a Department of Environment and Conservation (DEC) research scientist and can be contacted on (08) 9168 4217 or by email ([email protected]). Carolyn Thomson-Dans is a senior policy officer with DEC and has written and edited numerous books and LANDSCOPE articles. She can be contacted on (08) 9442 0300 or by email ([email protected]). Richard Fairman is a DEC fire technical officer and can be contacted on (08) 9168 4239 or by email ([email protected]). Ed Hatherley is DEC’s regional fire coordinator in the Kimberley and can be contacted on (08) 9195 5522 or by email ([email protected]).

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