Euastacus bindal is a species of small freshwater crayfish of the genus Euastacus. This species is less spiny than other members of the genus, with minimal spination on the abdomen and thorax in particular. However, the species does have two distinctive rows of spines along the fixed ‘finger’ of the claw (propodus). The species has a maximum size of approximately 37 mm in length from the eye region to the end of the main body segment (occipital carapace length (OCL)) and a maximum weight of approximately 34 g. The species colouration ranges from dull green to green-brown above and from dull orange to brownish-purple below. The top sides of the pincers are teal-blue to green in colour with a distinctive light-brown mottled pattern, while the undersides transition from a mottled light blue or blue-green colour near the tips to a mottled reddish or orange-brown colour near the base, and the spines are tinted yellow, reddish or orange-brown at the tips. Euastacus bindal is not likely to be misidentified, as it is readily distinguished from the only other species of freshwater crayfish occurring on Mt. Elliot (Cherax cairnsensis).
freshwater crayfish |
Status: Critically Endangered on the EPBC Act list
Government evidence of impact of climate change:
Australian Government, Conservation Advice, Euastacus bindal
Therefore; the species would be unable to retreat to an alternative location if its current habitat were compromised; or to move to higher ground in response to potential future climate change (Furse et al.; 2012a).Given its highly restricted range; Euastacus bindal is also extremely susceptible to stochastic events; such as localised impacts arising from natural disasters; severe weather events and bushfires (Furse et al.; 2012a).
Threat Threat type Threat Evidence base factor status Climate change Climate likely current and The increased temperatures; decreased rainfall change future and increased frequency of severe weather events that occur as a result of climate change pose a serious threat to this species.
Within Australia climate mediated threats; including impacts on water temperature and availability; are putting the conservation status of two thirds of all freshwater crayfish species at risk (Richman et al.; 2015).
Therefore; the species is unable to move into cooler environments in response to increasing temperatures (Furse 2010; 2014); Furthermore; the species has been shown to be at risk from natural disasters; including droughts; cyclones and other severe weather events (Furse et al.; 2012b); all of which are predicted to be exacerbated under climate change.
Climatic modelling of the Townsville region predicts increased temperatures; decreased rainfall and increased frequency of severe weather events under climate change (Hennessy 2006 IPCC 2007 Furse et al.; 2012a).
Therefore; E. bindal is likely to be particularly susceptible to climate change; which may lead to significant reductions in area of occupancy and number of mature individuals.
E. bindal was found to be highly sensitive to the impacts of climate change due to its specialised habitat requirements; narrow environmental tolerances (particularly thermal and precipitation tolerance) and its rarity (Hossain unpub. data; 2016).
The species was found to be highly exposed to climate change as a result of the predicted changes in mean temperature and precipitation within its geographic distribution (Hossain unpub. data; 2016).
Furthermore; studies on the thermal tolerance limits of other Euastacus species suggest that members of the genera are likely to be at risk from increasing environmental temperatures (Bone et al.; 2014); which are predicted by climate change modelling of the region (IPCC 2007).
Therefore; continuing declines in area; extent and or quality of habitat can be inferred based on likely impacts of climate change; including increased temperatures; decreased rainfall and increased frequency of severe weather events (Furse et al.; 2012a).
Similarly; species with such highly restricted extents of occurrence are extremely susceptible to the effects of small scale natural disasters; such as highly localised high intensity rainfalls; flash flood events and landslides; and any subsequent siltation events (Furse Coughran 2011b Furse et al.; 2012b).