Extensive and multiple bushfires ignited in Victoria on February 7th 2009. This date is routinely referred to as ‘Black Saturday’. These fires followed a long period of exceptional weather, with many records set for maximum temperature, heatwave duration and low rainfall (BOM 2009). Both Lake Mountain and Mount Bullfight Nature Conservation Reserve (NCR) were burnt by the ‘Murrindindi’ bushfire during the afternoon and evening of Black Saturday. The entire Lake Mountain plateau, including all woodlands, heathlands and mossbeds, was burnt (Figure 1). At Mount Bullfight NCR, 98% of the reserve was burnt; however, the fire was of a lower intensity than that at Lake Mountain (Tolsma and Shannon 2009).
Lake Mountain lies within the Yarra Ranges National Park in the Victorian Central Highlands, and Mount Bullfight NCR is situated approximately seven kilometres north-east of Lake Mountain. Parks Victoria co-manages the Lake Mountain plateau, with the skiing infrastructure managed by the Lake Mountain Alpine Resort under a Heads of Agreement. Parks Victoria is responsible for the management of Mount Bullfight NCR (Parks Victoria 2002).
1.3 Project background
In 2009, Parks Victoria received funding from the Australian Government’s Caring for Our Country fund to investigate the impact of the Black Saturday ‘Murrindindi’ fire on a range of threatened species. The results of the herpetofauna components of this work were reported by Howard et al. (2010) and Clemann and Antrobus (2010). Second year surveys were also funded by the Victorian and Commonwealth governments ‘Rebuilding Together’ – Statewide Bushfire Recovery Plan, announced in October 2009 This report documents the second season’s surveys for threatened herpetofauna at Lake Mountain and Mount Bullfight NCR.
1.4 Distribution and conservation status of the Alpine Tree Frog, Alpine Bog Skink and the Mountain Skink
1.4.1 The Alpine Tree Frog
The Alpine Tree Frog Litoria verreauxii alpina is listed as a threatened taxon under the Victorian Flora and Fauna Guarantee Act 1988. It is also listed as Critically Endangered by DSE (2007), and as Vulnerable nationally under the Environment Protection and Biodiversity Conservation Act 1999. A draft Victorian Action Statement (Clemann in prep.) and a draft National Recovery Plan (Clemann and Gillespie 2007) have been prepared for this
Historically, the Alpine Tree Frog was distributed across most of the high country of the south-eastern Australian mainland (Osborne et al. 1999) (Figure 2). Within this broader range, the frog has a small and fragmented geographic distribution due to its restriction to isolated mountain peaks and plateaux. Within Victoria, records of the Alpine Tree Frog extend from the vicinity of Tom Groggin in the north-east of the state, across the higher altitudes of the Great Dividing Range, to Mt Baw Baw in
the south-west of the taxon’s range (Figure 2).
The Alpine Tree Frog occurs in high montane, subalpine and alpine environments. It is a habitat generalist, recorded in a range of terrestrial habitats including woodland, heath, grassland and herb fields, and human modified habitats. Although the Alpine Tree Frog was once common and abundant throughout its range, there have been severe declines in recent decades (Clemann and Gillespie 2007), including local extinctions e.g. Mount Baw Baw and the Bogong High Plains. Alpine Tree Frogs were common at Lake Mountain during the 1960’s, with the last voucher specimen collected in 1970. Only one Alpine Tree Frog has been recorded at Lake Mountain since then, in 1993 (Victorian Fauna Database). Unfortunately this individual was only heard and not observed. Therefore this record should be treated cautiously given known declines, uncertainty in taxonomy, and the similarities between the call of the Alpine Tree Frog and related species. The Alpine Tree Frog was first recorded at Mount Bullfight NCR in December 2009, during the first year of this study
(Howard et al. 2010).
The draft National Recovery Plan for Alpine Tree Frogs lists disease (chytridiomycosis, caused by the Amphibian Chytrid Fungus) and climate change as major threats (Clemann and Gillespie 2007). The Amphibian Chytrid Fungus has been strongly implicated in the declines of amphibians worldwide (Berger et al. 1999). The disease has been detected in Alpine Tree Frog populations in the Snowy Mountains, the Dargo High Plains and around Mount Hotham (Hunter et al. 2008, Clemann et al. 2009). Another potential threat is the likely increase in the frequency, extent and severity of wildfire due to climate change or extended periods of drought.
1.4.2 The Alpine Bog Skink
The Alpine Bog Skink Pseudemoia cryodroma is only known from Victoria, where it is listed as threatened under the Flora & Fauna Guarantee Act 1988. It is also listed as Endangered in Victoria by DSE (2007). Alpine Bog Skinks are restricted to the north-eastern highlands in Victoria (Figure 3). Although Alpine Bog Skinks have not been recorded in New South Wales, the presence of populations close to the border (at Davies Plain), and the difficulties in capturing and identifying the species (Clemann 2002a), suggest that it may yet be detected in alpine areas of southern New South Wales.
Alpine Bog Skinks occur in alpine and subalpine habitats above 1000 m elevation. They commonly occur in bogs, boggy creeks, alpine grasslands and wet heath, and less commonly in dry heath and Snow Gum woodland (Hutchinson and Donnellan 1992, N. Clemann unpublished data). Although sympatric with the Tussock Skink
P. pagenstecheri and Southern Grass Skink P. entrecasteauxii, the Alpine Bog Skink tends to occur in wetter microhabitats than the Tussock Skink, and more open areas than the Southern Grass Skink (Hutchinson and Donnellan 1992). The similarities between the Pseudemoia species often makes it difficult to confidently identify individuals. Maggie Haines (Melbourne University) is completing a PhD studying the genetics of the Pseudemoia genus. It is hoped that this study will remove the ambiguity associated with identifying members of this genus of skinks.
A draft Action Statement (Clemann in prep.) prepared
for Alpine Bog Skinks identifies several threats to the species, including:
• climate change;
• loss and degradation of habitat due to development of roads, tracks, ski resort infrastructure, weed invasion, inappropriate fire regimes, grazing and trampling by exotic herbivores (cattle, horses, deer);
• direct mortality due to fire;
• direct mortality due to elevated levels of predation by exotic predators (Feral Cats Felis catus and Red Foxes Vulpes vulpes); and
• extreme vulnerability of populations to stochastic events such as disease.
1.4.3 The Mountain Skink
The Mountain Skink Liopholis montana is a recently described species (Donnellan et al. 2002) that occupies montane, subalpine and alpine areas, typically in open forest, snow gum woodlands and heathland in the uplands of south-eastern Australia. The occurrence of Mountain Skinks is usually linked to granite boulders, slabs or rock screes. Mountain Skinks are a burrowing species that typically shelter in elaborate burrow systems excavated beneath rocks (Chapple 2003). Although not well known, it is likely that this species’ distribution is disjunct. Within Victoria records exist from the upper Yarra Valley, along the higher elevations of the Great Dividing Range, to Davies Plain in the far north-east of the state. Mountain Skinks
are listed as Data Deficient by DSE (2007).