Looking for mice in the mangroves
By Cheryl Bolzenius, WetlandCare Australia
Last year WetlandCare Australia initiated the Coastal 20 (C20) Wetlands Program to celebrate 20 years of achievement in wetland conservation. The Australian Government committed a $2.5 million budget for the program through a Caring for Our Country contract. The program involves working in partnership with community, government and industry to rehabilitate 20 important wetlands from Gladstone in southern Queensland to Kempsey on the northern NSW coast. A total of 37 Site Action Plans were approved by the project steering committee and on-ground action is now underway.
One of the C20 sites covers 65 ha of mangrove, casuarina and marine grassland on the Maroochy River, on Queensland’s Sunshine Coast. In late 2011, a worker from the Queensland Parks and Wildlife Service (QPWS) discovered several water mouse (Xeromys myoides) nests at the site. The water mouse inhabits coastal areas of central and SE Queensland, Northern Territory and New Guinea, and is typically found in coastal saltmarsh and mangrove areas. A key sign of their presence is their nesting mounds, which range from free-standing mounds in saltwater couch grasslands to sheltered mounds in opportunistic sites such as the base of old grey mangrove trees (Avicennia marina) located within the intertidal zone. The water mouse forages in the mangroves at night, feasting on invertebrates such as crabs, shellfish and snails. Loss, fragmentation and degradation of their mangrove and saltmarsh habitats are key threats to their survival. The water mouse is listed as nationally vulnerable and was previously unknown at the C20 Maroochy River site.
WetlandCare Australia is now working with ecologist Nina Kaluza (BEnSc), QPWS and community volunteers to survey and monitor water mice along a 1.7 km stretch of the Maroochy River covering several land tenures. We have located and mapped 114 nesting mounds in total, and recorded information on their distribution, habitat preference and potential threats including erosion and invasive weeds.
The Coastal 20 project has also enabled Traditional Owners to undertake rehabilitation to address threats and protect this specialised mammal’s habitat. Weed control along the banks of the Maroochy River is underway to remove broad-leaf pepper tree (Schinus terebinthifolius), singapore daisy (Sphagneticola trilobata) and ground asparagus (Asparagus aethiopicus cv. Sprengeri). Mangroves are being propagated and reinstated to prevent further erosion of coastal saltmarsh. The habitat rehabilitation will also benefit many threatened and migratory species that rely on these vegetation communities.
WetlandCare Australia and the project team have developed an informal network to share knowledge with similar water mouse projects in SE Queensland including the Great Sandy Strait region. We envisage that data collected through these projects will guide future conservation activities and support key actions identified in the national recovery plan for the water mouse.
Water Mice and their mound nest, captured on a motion sensor monitoring camera.
Photo: Nina Kaluza
Nina Kaluza and staff from WetlandCare Australia and QPWS undertaking site surveys of Water Mice mounds.
Photo: Adam Gosling