The Pulse of Gwydir Water availability Four species, the broad-palmed rocket in 2015–16 in the frog, spotted marsh frog, barking marsh frog, 2015–16 and eastern sign-bearing froglet, bred in the Northern Basin wetlands of the lower Gwydir system in response to In the Gwydir, Junction of environmental water. the Warrego and For the first time since 2013, a population of 78 GL threatened olive perchlet was seen in large Darling, and Lachlan rivers delivered numbers in the Gwydir. Environmental water was Total available critical to maintaining flow into the Gingham Waterhole for use Scientific monitoring and evaluation of where the olive perchlet were observed. 156.4GL environmental water use helps all water Condamine–Balonne Three other threatened species were also seen including users to better understand flow regimes Moonie , silver perch and the freshwater catfish. and their various components. This work is (Lower Balonne) Border Rivers This confirms that positive ecological outcomes can helping to improve understanding about be achieved by using relatively small amounts of how flows relate to the health and diversity environmental water at critical times, particularly during Queensland of fish and bird populations, vegetation Warrego periods of low or no river flow. Northern and ecosystems as well as water quality allocation: New South Wales and river hydrology (water flow and water 69.4 GL connectivity to wetlands and floodplains). Gwydir The western population of the olive perchlet was once widespread throughout the Murray-Darling system of South Australia, Paroo Namoi Victoria, western New South Wales and southern Queensland. This population has suffered a serious decline and is now found only at a few Barwon-Darling sites in the drainage. Macquarie

Junction of Warrego and Darling rivers (Toorale) Lower Darling An outbreak of the floating aquatic weed Azolla Murray Lachlan in part of the Darling River channel was dispersed following flows in spring 2015 which included environmental water, preventing potential decline in water quality. Flows in the Darling River supported connectivity and provided native fish with access to habitats such as snags and anabranches. These flows helped maintain water quality throughout the year. Murrumbidgee There was a notable increase in fish populations Olive perchlet. Credit: Murray-Darling Basin Authority such as the bony herring and spangled perch in the in March 2016, compared to Edward-Wakool 59 waterbird species were recorded, including Carryover: October 2015. Environmental flows upstream of Toorale Murray contributed to connectivity along the length of the river Eastern five species listed under theNSW Threatened Mt Lofty Loddon 87 GL and supported breeding and recruitment of native fish Wimmera-Avoca Species Conservation Act 1995; the brolga, Ranges Ovens including bony herring, spangled perch, golden perch and Goulburn magpie goose, black-tailed godwit, black falcon and Hyrtl’s catfish. -Broken black-necked stork. These birds benefited from habitat maintained using environmental water. Small-scale 87 species of birds were seen in the Warrego Victoria waterbird breeding was supported for 16 species; River and the Western Floodplain, including three Campaspe however, as expected, the overall abundance and species listed under international migratory bird breeding activity was smaller than the wetter conditions agreements; the wood sandpiper, common sandpiper and in 2014–15. eastern great egret. Waterbird numbers and diversity were higher in drought refuge sites along the Warrego. Wetland vegetation improvements from previous watering years were maintained through a dry year with small but significant contributions of environmental water. These wetland vegetation species included water couch, spike- rush, tussock rush, lignum and river cooba, and floodplain species such as coolibah and river red gum. Significantly, areas of water couch meadow that received environmental water were shown to have reduced Lachlan Small flows delivered to the Booligal coverage of lippia, an invasive weed species. Wetlands helped the breeding of four When a storage has reached a certain Environmental water was released down the Native fish populations benefited from high species - the spotted marsh frog, barking capacity, a small amount of water is allowed lower Gwydir, Gingham, Mehi and Carole channels flows created by the combination of water marsh frog, eastern sign-bearing froglet and the to flow through river systems to replicate a in April 2016 providing critical connection between released from storage under “translucent flow” great banjo frog. Successful recruitment of the natural response to rainfall. This is known isolated refuge pools, sustaining native fish, invertebrate arrangements and environmental flows. Seven native spotted marsh frog and the great banjo frog also as translucent flow — a type of planned and other aquatic communities. Brolgas at Toorale Station. Credit: L. Copeland fish species spawned including Australian smelt, Murray occurred in Murrumbidgil Swamp. environmental water event intended to restore cod, carp gudgeon and flat-headed gudgeon. However, natural medium to high flows, seasonality, and there was no evidence (eggs or larvae) that golden flow variability. However, they are independent perch responded to environmental water in 2015–16. of Commonwealth environmental water flows. The timing of flows in relation to unseasonably high Translucent flows are triggered according to river temperatures may have contributed to this. specific rules that apply to individual storages Improvements in foliage cover, decreased dead as per State water sharing plans. For further canopy and the health of native riverbank and information, please refer to www.water.nsw. wetland vegetation such as red-gum and black gov.au/watermanagement/water-sharing/ box trees occurred at sites that were inundated. environmental-rules/rivers#flows

For further information on environmental water Popular pastime at Toorale Station Straw-necked Ibis eggs. Credit: J. Spencer Pink-eared and blue-billed ducks management, in the unregulated rivers of the Northern Basin refer to www.environment.gov.au/water/ cewo/publications/restoring-protecting-northern- basin-2016-17 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 Murray rivers delivered silver perch (EPBC Act). In wetlands, carp gudgeon, Australian smelt and bony herring successfully recruited, Total available Scientific monitoring and evaluation of and Murray cod juveniles were seen in the Nimmie-Caira environmental water use helps all water for 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 and their various components. This work is habitats and maintained water quality in the Border Rivers helping to improve understanding about Nimmie-Caira, Redbank and mid-Murrumbidgee how flows relate to the health and diversity wetlands. This stimulated micro-invertebrate populations, Queensland of fish and bird populations, vegetation Warrego which support wetland and riverine foodwebs, increasing and ecosystems as well as water quality food supply for fish, , turtles, waterbirds and other and river hydrology (water flow and water South Australia New South Wales . connectivity to wetlands and floodplains). Gwydir Waterbirds such as threatened Australasian bitterns (EPBC Act), freckled ducks and magpie geese were recorded foraging and nesting, with some breeding in wetlands where environmental water Paroo Namoi had been contributed. Barwon-Darling Nine aquatic plant communities and 43 water-dependent species were recorded across 12 wetlands. In Yarradda Lagoon important Macquarie water dependant native species, including spiny mud Southern grass, tall-spike rush and fringe lily re-established allocation: following successive years of environmental watering. Environmental water reduced salinity levels in Lower Darling 937.6 GL the Lower Murray Channel, Lower Lakes, Coorong Breeding activity for six frog species (plains Lachlan and 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 marsh) was recorded. The Vulnerable southern bell frog 100 per cent of flows between November 2015 and was recorded at Yarradda Lagoon for the first time since June 2016 into the Coorong. the 1970s. 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 recruitment of golden and silver perch in the Ranges Goulburn Ovens Barmah-Millewa forests, Hattah Lakes, and Lower Murray. Compared to the previous year, the -Broken wetlands throughout the Victorian-NSW Mallee number and diversity of small-bodied fish remained high; region, South Australian Riverland, Lower however, there was an increase in the number of exotic Lakes and Coorong. These flows sought to Victoria goldfish and common carp. Campaspe support in-channel, wetland and low elevation floodplain habitat, thereby improving the For the second consecutive year, small Murray cod condition, movement and recruitment of native were found in the Lower Murray, indicating successful fish (including Murray cod, silver and golden recruitment. The contributing conditions that supported perch), the condition of riparian and wetland this recruitment remain unclear. vegetation and 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 Long-distance movements of golden perch buffered against the effects of the particularly the importance of providing connectivity and forests and nearby floodplains was reused were detected frequently, with one fish dry conditions, as reduction in numbers was less severe passageway between these parts of the system to along the length of the Murray River, including travelling around 600km from the Goulburn in the Goulburn River following environmental water support a healthy fish population. the Edward-Wakool system resulting in connectivity River, through the Murray River and to the junction use, than in the nearby Broken River which received no Carryover: between the Yallakool Creek and parts of the Wakool of the Wakool River in two months. These results environmental water. 357 GL River. The timing of these flows was early enough in the highlight the importance of hydrological and biological Spring environmental flows improved native season that carbon inputs from the floodplain to the river connectivity in the management of flow and habitat for vegetation abundance and diversity along channels were achieved without causing water quality golden perch across catchments. issues in the Edward-Wakool system. areas of riverbank. This builds on past efforts Over the past two years, endangered have to 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 Lower Goulburn River close to the Murray. It is not known support plants and manage bank erosion. mid 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. Credit: Murray-Darling Basin Authority.