The Pulse of Murrumbidgee Water availability Environmental water was delivered to around in 2015-16 in the 16,000 hectares on the Lowbidgee floodplain 2015-16 supporting water quality. Southern Basin In the Murrumbidgee, Native fish numbers in wetlands increased from the previous year. The delivery of water to Edward-Wakool, Goulburn wetlands coincided with spawning in at least nine 970 GL native species of fish including the critically endangered and delivered silver perch (EPBC Act). In wetlands, carp gudgeon, Australian smelt and bony herring successfully recruited, Total availble Scientific monitoring and evaluation of and juveniles were seen in the Nimmie-Caira for environmental water use to help all water the first time since monitoring began in 2008. for use Condamine–Balonne users to better understand flow regimes Moonie 1294.5GL (Lower Balonne) Watering supported wetland and refuge habitats and their various components. This work is and maintained water quality in the Nimmie- Border Rivers helping to improve understanding about Caira, Redbank and mid-Murrumbidgee wetlands. how flows relate to the health and diversity This stimulated micro-invertebrate populations, which Queensland of fish and bird populations, vegetation Warrego support wetland and riverine foodwebs, increasing food and ecosystems as well as water quality supply for fish, , turtles, waterbirds and other and river hydrology (water flow and water New South Wales . connectivity to wetlands and floodplains). Gwydir Waterbirds such as threatened Australasian bitterns (EPBC Act 1999), freckled ducks and magpie geese were recorded foraging and nesting, with some breeding in wetlands where Paroo Namoi environmental water had been contributed. Barwon-Darling Nine aquatic plant communities and 43 water- dependent species were recorded across 12 wetlands. In Yarradda Lagoon important water Macquarie Murray River dependant native species, including spiny mud grass, Southern tall-spike rush and fringe lily re-established following allocation: successive years of environmental watering. Environmental water reduced salinity levels in the Lower Darling 937.6 GL Lower Murray Channel, Lower Lakes, Coorong and Breeding activity for six species (plains Lachlan Murray Mouth. It also transported nutrients Murray froglet, barking marsh frog, inland banjo frog, throughout the river system, providing food for aquatic perons tree frog, southern bell frog and spotted plants and animals. Environmental water provided 100 marsh) was recorded. The Vulnerable southern bell frog per cent of flows between November 2015 and June 2016 was recorded at Yarradda Lagoon for the first time since into the Coorong. the 1970’s. Using environmental water to raise weir pools in the Lower Murray provided higher connections between the floodplain and the river, which in turn provided more Commonwealth environmental flows occurred fish food. In years of relatively low flow, changes in weir Murrumbidgee in the Mid–Murray and Lower Murray, from Hume pool levels in conjunction with environmental water use Dam through to the Coorong, Lower Lakes and can maximise ecological benefits between the river and Murray Mouth to support the management of floodplain, such as nutrient exchange and wetting of Edward-Wakool Australia’s wetlands of international importance fringing vegetation. Eastern Murray (Ramsar listed wetlands) and sites that support Loddon Due to low flows, there was little spawning and Mt Lofty Wimmera-Avoca nationally threatened species including Barmah- recruitment of golden and silver perch in the Ranges Goulburn Ovens Millewa forests, Hattah Lakes, and wetlands Lower Murray. Compared to the previous year, the -Broken throughout the Victorian-NSW Mallee region, number and diversity of small-bodied fish remained high, South Australian Riverland, Lower Lakes and however, there was an increase in number of exotic Coorong. These flows sought to support in- Victoria goldfish and common carp. Campaspe channel, wetland and low elevation floodplain habitat thereby improving the condition, For the second consecutive year, small Murray cod movement and recruitment of native fish were found in the Lower Murray, indicating successful (including Murray cod silver and golden perch) the recruitment. The contributing conditions which have condition of riparian and wetland vegetation and supported this recruitment remains unclear. the managed export of salt from the River Murray.

Otolith (ear bone) analysis of fish in the lower Murray shows that the population is made up of fish from all over the southern connected Edward-Wakool Goulburn River Although macroinvertebrate numbers declined Murray-Darling Basin, including from the in 2015–16, environmental water may have Darling and Upper Murray Rivers. This highlights Water delivered to the Barmah-Millewa forests Long-distance movements of golden perch buffered against the effects of the particularly the importance of providing connectivity and and nearby floodplains was reused along the were detected frequently, with one fish dry conditions, as reduction in numbers was less severe in passageway for between these parts of the system length of the Murray River, including the Edward- travelling around 600km from the Goulburn the Goulburn River following environmental water use, to support a healthy fish population. Wakool system resulting in connectivity between the River, through the Murray River and to the junction of than in the nearby Broken River which received no Carryover: Yallakool Creek and parts of the Wakool River. The timing the Wakool River in two months. These results highlight environmental water. 357 GL of these flows was early enough in the season that carbon the importance of hydrological and biological Spring environmental flows improved native inputs from the floodplain to the river channels were connectivity in the management of flow and habitat for vegetation abundance and diversity along achieved without causing water quality issues in the golden perch across catchments. Edward-Wakool system. areas of riverbank. This builds on past efforts to Over the past two years, endangered have improve and re-establish aquatic and semi-aquatic Lake Eildon Native fish diversity and condition was been found below Shepparton, which may indicate a plants through consistent flows of environmental water maintained. Growth of the Murray cod population recent expansion in range since 2003 when they were during spring. (those not released from hatcheries) remained only found further upstream. steady in 2015-16 indicating that spawning is resulting in Carefully managed declines in environmental flows can Spawning was detected for five native fish including the successful recruitment. allow a layer of mud to be deposited onto the riverbank Murray cod, Australian smelt, carp gudgeon, flathead that provides an ideal location for the germination There has been gradual improvement in the gudgeon and Murray River rainbowfish. and growth of new plants. This activity will be a focus diversity and cover of riverbank and aquatic Large numbers of young carp were found in a reach of the of future monitoring in the interests of continuing to plants at sites in Yallakool Creek and the mid Lower Goulburn River close to the Murray. It is not known support plants and manage bank erosion. Wakool River that have consistently received whether this breeding was enhanced by the delivery of environmental water over the past five years. environmental water in early spring to support plants on the riverbank, or whether carp spawned in the Murray and moved into the Lower Goulburn River. Murray Cod. Credit: Murray Darling Basin Authority. Fishing on the Murray River, Murray-Darling Basin Authority.