The water mouse is a small rodent with short, dense silky fur that is dark slate-grey above and pure white below (Van Dyck and Strahan 2008). The water mouse occurs in three regions of coastal Australia: The Northern Territory, central south Queensland and south-east Queensland. Maps of these regional sub populations are provided in the draft significanty impact guidlines for the water mouse (see link above). The species may occur in the Kimberley region of Western Australia due to its close proximity with populations in the Northern Territory and the location of suitable habitat (Morris 2000). Within its range, it is patchily distributed and no where is it particularly abundant (Gynther & Janetzki 2008). Detail on the locality and extent of these known sub populations is provided in the national recovery plan. Since inception of the national recovery plan, significant new sub populations have been confirmed in Moreton Bay, which includes Pumicestone Passage between Bribie Island and the mainland (Gynther 2011). In the Sunshine Coast region along the Maroochy River system a combined total of 214 water mouse nests over 200ha of wetlands have been recorded since February 2012; locations include Glass Mountain, Hussey and Bells Creeks (pers.comm Nina Kaluza). Further north sub populations have been identified in the Gladstone harbour and at Laird Point on Curtis Island (QGC 2013).
Water Mouse, False Water Rat, Yirrkoo |
Status: Vulnerable on the EPBC Act list
Government evidence of impact of climate change:
Australian Government, Conservation Advice, Xeromys myoides
These wetland systems are susceptible to a variety of factors; including land use change; increasing human presence; invasive species and climate change (Eslami Andargoli et al. 2009).
Climate change Saltwater intrusion Status current future Climate change is leading to rising sea levels causing Confidence habitat loss and degradation from saltwater known inferred intrusion.
Consequence major In northern Australia; floodplain wetlands are Trend increasing highly susceptible to change caused by rises in sea Extent across the entire levels from global climate change; resulting in range; current in Top productive freshwater habitats being replaced by End part of range saline systems (DERM 2010 Traill et al. 2011).
Increased extreme weather Status current future Climate change is leading to an increase in events i.e cyclonic events; Confidence frequency and intensity of wildfires causing habitat storm surges and or spring known inferred loss and degradation (Ward et al. 2020) and sudden tides to impact on the Water Consequence major and temporary drops in sea levels resulting in mass Mouse and its habitat. mangrove dieback (Duke et al. 2017).
Climate change and extreme weather events Improve the resilience of Water Mouse habitats by removing or managing the impacts of local processes; such as feral pig damage; fires and weed invasions.
Wildfire is a Trend increasing major threat to Water Mouse habitat (Ward et al.
Fire is known to range directly impact Water Mouse mound nests and hollow bearing trees along intertidal areas of saltmarsh and sedge grass communities (Van Dyck and Gynther 2003) and fire also exposes the Water Mouse population to increased predation by foxes and cats (Kaluza 2019).
Weed invasion Status current The spread of exotic pasture grasses poses a threat Confidence known to the Water Mouse; modifying habitat and Consequence major increasing fire intensity and risk to Water Mouse habitat (Woinarski et al. 2011).
Most pastoralism Trend increasing relies on native grasses but; increasingly; non native Extent across part of its (mostly African) grass species have been introduced range (and spread beyond pastoral lands which radically alter understorey composition and structure; produce biomass far in excess of that of native grasses; and hence fuel fires of far greater intensity; exacerbating habitat degradation (Rossiter et al. 2003).