|Scientific Name:||Euastacus girurmulayn|
|Species Authority:||Coughran, 2005|
|Red List Category & Criteria:||Critically Endangered B2ab(iii) ver 3.1|
|Assessor(s):||Furse, J. & Coughran, J.|
|Reviewer(s):||Collen, B. & Richman, N.|
|Contributor(s):||Livingston, F., Livingston, F., Soulsby, A.-M., Batchelor, A., Dyer, E., Whitton, F., Milligan, H.T., Smith, J., Lutz, M.L., De Silva, R., McGuinness, S., Kasthala, G., Jopling, B., Sullivan, K. & Cryer, G.|
Euastacus girurulayn has been assessed as Critically Endangered under criterion B2ab(iii). This species has a severely fragmented distribution, and an area of occupancy of 6.5 km2. There has been a continuing decline in the quality of habitat due to the destructive nature of a number of exotic species in the area, some of which also predate upon this species. There is also destruction of suitable rainforest habitat in parts of its range, and a very high risk of pollution incidents with management of the national park and the high numbers of visitors in the area. This species also faces the consequences of global temperature rise. As a restricted range species, dependent on cool, clear headwater streams, a slight increase in temperature could rapidly extirpate this species. Research is needed on the thermal tolerances and hydrological requirements of this species to enable predictions of potential reduction in their distribution, habitat, and abundance due to anthropogenic climate change. A better understanding of this species habitat requirements and key threats will enable effective conservation measures to be prescribed.
|Range Description:||This species is endemic to New South Wales, Australia. It is currently known from only three localities, Tuntable Creek in Nightcap National Park, Gibbergunyah Creek, and a gully in the Cooper's Creek catchment, both within the Whian Whian National Park (New South Wales). All individuals were collected between 460 m and 580 m above sea level. Extent of occurrence is estimated to be 396 km² and area of occupancy has been estimated at 6.5 km² (Coughran 2007). The localities are rainforested headwaters of different streams, and should be regarded as severely fragmented due to the effective barrier to dispersal by the intervening lowland areas (Morgan 1997, Ponniah and Hughes 2006).|
Native:Australia (New South Wales)
|Estimated area of occupancy (AOO) - km2:||6.5|
|Range Map:||Click here to open the map viewer and explore range.|
|Population:||There are no population data available for this species, however it is uncommon at the sites it inhabits (J.M. Furse and J. Coughran pers. comm. 2008).|
|Current Population Trend:||Unknown|
|Habitat and Ecology:||This species occupies different habitat types at each site, including a gully and headwater streams. Individuals were collected from both shallow excavations under rocks, and complex burrow networks. All sample sites were within closed forest cover (Coughran 2007).|
|Use and Trade:||This species is taken from the wild by collectors.|
Despite being found in a national park and a state conservation area, this species may also be adversely affected by pesticides and pollution associated with the maintenance of the areas. These could be herbicides or pesticides, or as a result of visitation. e.g. vehicle pollution, or infected trapping gear. As this species occurs in an area of high visitation there is a very real risk of pollutant or infectant introduction (Coughran 2007). Wildfire or management burns may also lead to siltation and deoxygenation of habitats.
Although this species occurs within a national park it is susceptible to the following potential threats: 1. Given its highly restricted range, the species is extremely susceptible to localized impacts, including bush fires, forest management practices, habitat destruction and over exploitation by collectors; 2. Climate change, including increasing temperature, alterations to hydrological regimes, severe weather events, loss of suitable rainforest habitat and increased potential for bushfires (Chiew and McMahon 2002, Howden 2003, Hughes 2003, Pittock 2003, Hennessy 2006, Westoby and Burgman 2006, IPCC 2007); 3. There is a potential large scale threat from Cane Toads (Rhinella marina) (DEH 2004a) although there are no specific data on impacts for this species; 4. Other exotic species (cats, foxes, pigs, goats) that have generally been found to impact on crayfish (e.g. Green and Osbourne 1981, Horwitz 1990, Merrick 1995, Eyre et al. 1997, ACT Government 2007, O’Brien 2007) also occur in this species’ range (DEH 2004b,c,d,e). Given this species highly restricted distribution, these exotic species could have serious impacts on E. girurmulayn and lead to serious declines in distribution and/or abundance. Due to the narrow thermal tolerance of this species, and its restricted range (restricted to cool, headwater streams in forested catchments), global temperature increase has resulted in range contraction. This species is further compromised by the presence of exotic species (feral pigs, goats, foxes, Cane Toads and cats) which are known to predate on crayfish and degrade riparian habitat; while the precise effects of these threats on this species are not yet well understood, they are believed to be significantly impacting the long term viability of the population (J. Furse and J. Coughran pers. comm. 2010).
There are no species-specific conservation measures in place for this species, however its distribution range falls within the Whian Whian and Nightcap national parks. Further research is needed on the possible threats impacting this species. Research should be initiated to include population assessment and monitoring, biological and life history information, habitat requirements, investigations into thermal tolerance and resilience to exotic species.
In New South Wales, a minimum recreational size limit of 90 mm Orbital Carapace Length is in place for any spiny crayfish (NSW DPI 2007). This crayfish species does not attain that size, and so is indirectly protected by this restriction.
|Citation:||Furse, J. & Coughran, J. 2010. Euastacus girurmulayn. The IUCN Red List of Threatened Species 2010: e.T153646A4526116. . Downloaded on 10 February 2016.|
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