Water for the Environment News

The 2012-13 water year began with many dams at high capacity, water readily available and wetlands with two very wet years under their belt. However, climate forecasts predict average to below-average rainfall for the coming summer.

The watering priorities across the valleys reflect the favourable watering conditions and include:

• inundating wetlands to build on the positive ecological response seen in the last two years and support bird breeding events
• delivering in-channel flows to support native fish habitat and breeding.

If conditions turn dry, as climate forecasts predict, water is likely to be available to be carried over for future years.

Derek Rutherford, Director Water, Wetlands and Coast Division (OEH), describes the guiding plans as flexible, allowing OEH water managers to factor in weather and river conditions and respond to opportunities and changes in water resources, as well as monitoring key wetland species.

'The health of NSW wetlands has generally improved thanks to two years of near-record rainfall and environmental water delivered by OEH to extend the duration and extent of flooding to enable plants and animals to breed successfully,' Derek says.

'However, in wetlands that lost long-lived tree species such as river red gums, restoration of some habitat components is a long-term objective.

'Recruitment of young animals and the setting of seeds are our best insurance policy to ensure the continuation of species and build ecosystem resilience,' Mr Rutherford concluded.

Dr Jennifer Spencer, Environmental Scientist (OEH), says that wetland monitoring in the Murrumbidgee Catchment has shown that floodplain wetlands provide important habitats for a range of native fish species, from small-bodied gudgeons, smelt and rainbowfish to larger bony bream and golden perch.

'Most native fish species increased in abundance with increasing wetland area. This was most noticeable in golden perch which became more widespread in the wetlands after large floods,' Jennifer says.

As the state’s environmental water manager, OEH is able to deliver environmental water that recreates aspects of natural river flows important for supporting native fish by:

• providing cues for fish breeding
• assisting the dispersal of eggs, larvae and juvenile fish
• allowing adult fish to move to new habitats to maintain diversity in populations
• providing refuges during drought or other extreme events
• maintaining nutrient supply and water quality at standards suitable for fish growth and survival.

During October and November this year, OEH delivered an environmental flow of nearly 250,000 megalitres to the Murrumbidgee River to support Murray cod and encourage trout cod and golden perch to breed. Both Murray cod and trout cod are listed as threatened species.

This flow comprised water from the NSW Government, the Commonwealth and The Living Murray initiative.

More information on the recent monitoring of native fish in the mid-Murrumbidgee wetlands by a number of agencies

Full results of the 2011-12 monitoring of the mid-Murrumbidgee wetlands

'Water and Wetlands' is one of the 'themes' of the Knowledge Strategy. Dr Neil Saintilan (OEH) led the process to prioritise actions to address the knowledge needs for this theme. These actions were first implemented in 2011, then reviewed and updated for 2012-13.

Some of OEH's top priorities for the Water and Wetlands theme are to:

• support environmental water management by improving monitoring and modelling techniques
• assess river, wetland and groundwater-dependent ecosystem extent and condition in partnership with the NSW Office of Water, to meet our obligations under the NSW Monitoring, Reporting and Evaluation Strategy
• identify ecological assets and their water requirements to support Rural Floodplain Management Plans.

Each priority action under the Knowledge Strategy, such as vegetation monitoring, helps water managers understand how ecosystems respond to environmental water, how resilient the biodiversity is, and how vegetation communities are faring now that things are wetter after the drought. But, unlike vegetation monitoring, many actions don't involve going out to gather new data.

'Often the knowledge already exists, but it's hard to access or use,' Neil says. 'The Knowledge Strategy process highlights these issues so we can work to ensure that everyone who needs the knowledge has access to it. For example, my team is working with CSIRO to help them get the most from existing tools and systems."

Email knowledge.strategy@environment.nsw.gov.au for more information.

Poor management of unsealed roads can lead to erosion and sediment runoff which may in turn flow into local waterways, causing environmental harm and resulting in costly repairs. Sediment runoff can cause siltation of river channels and fill wetlands. It also reduces light penetration and can lead to a loss of habitat and spawning sites for some fish.

Poor management can also be a safety hazard and lead to expensive repairs.

The field guide was initially developed for use in national parks but has now been refined and released for wider use. The guide provides support for those looking after unsealed roads to reduce soil erosion and minimise the amount of sediment entering the waterways. It recommends regular maintenance, with additional inspections after heavy rain, and provides practical advice on identifying problems and hands-on solutions.

The guide is free and has been designed to fit into a vehicle's glove box and OEH is hoping that it will become an indispensible tool for many land and road managers.

Paul Packard, Senior Wetlands and Rivers Conservation Officer (OEH) says that the Lachlan Valley Annual Environmental Watering Plan 2012-13 (120766lachlanwp.pdf, 1.7MB) reflects the significant flows and duration of inundations that have occurred over the past two years and the extensive ecological responses now occurring.

'In other wetland areas vegetation such as Lignum is growing vigorously and beginning to re-occupy those areas where wetland vegetation had died back due to reduced flows, compounded by the recent drought conditions,' says Paul.

Environmental water will also be used this year to support colonial bird breeding and build stronger fish populations by maintaining fish refuge and boosting fish movement and breeding.

Formed in 2009 by the Lachlan CMA to advise OEH on the use of environmental water, the Lachlan Riverine Working Group has won two 2012 Green Globe Awards and was shortlisted for a Banksia Award. On 3 September 2012, Robyn Parker, Minister for the Environment presented the group with a Water Award and the Regional Sustainability Award for their demonstration that successful partnerships between government, irrigators, graziers, environmental and Aboriginal groups can be established to benefit riverine and wetland health.

Find out more about environmental water and the Lachlan Valley, including the condition of wetland assets and the Lachlan Valley Annual Environmental Watering Plan 2012-13 (120766lachlanwp.pdf, 1.7MB).

The nationally endangered Australian painted snipe and the vulnerable magpie goose, freckled duck, black-necked stork and brolga were spotted.

Breeding was observed in at least 31 species of waterbird, including waterfowl, rails and crakes, cormorants, ibis and egrets.

Waterbirds Return as the Gwydir Floods photo-essay celebrates the successful 2011-12 colonial waterbird breeding event.

The Gwydir Environmental Contingency Allowance Operational Advisory Committee has endorsed a 'whole of season' watering approach to continue the good inundation of wetlands and build on the environmental outcomes of the previous two years.

Find out more about environmental water and the Gwydir Valley, including the condition of wetland assets and the Gwydir Valley Annual Environmental Watering Plan 2012-13 (120763gwydirwp.pdf, 1.8MB).

OEH continues to provide the environmental water flows needed by Murray and Lower Darling wetlands following a decade of drought. Environmental water allocations will be used to:

• help improve the health of stressed vegetation
• support recruitment of fauna communities, especially waterbirds, native fish and frogs
• complement naturally occurring high river flows to maximise benefits to wetland plants and animals
• assist in furthering our understanding of the biological processes and functions within wetlands and riverine habitats and better inform future management of environmental water.

Several projects are underway ranging from watering smaller private wetlands to larger scale collaborative efforts with landholders, and federal and state agencies which provide in-stream flows to benefit native fish.

Paula D'Santos, Senior Wetlands and Rivers Conservation Officer (OEH) says that the most encouraging results this season included the almost immediate response by riparian vegetation and the presence of the endangered southern bell frog in the Gwynnes Creek system.

'This system is located in the mid-Murray and has been dry for around 40 years and it's always terrific to see it able to respond so quickly. Landholder support has been amazing. We often receive phone calls and photographs from locals who are thrilled with the response,' says Paula.

Find out more about environmental water and the Murray and Lower Darling Valleys, including the condition of wetland assets and the Murray and Lower Darling Valleys Annual Environmental Watering Plan 2012-13 (120765murraywp.pdf, 1.7MB).

Debbie Love, Senior OEH Wetlands and Rivers Conservation Officer, says that vegetation in the marsh wetlands has benefitted from combined environmental water releases and flood conditions during 2010-12.

'The Macquarie and Cudgegong Environmental Flows Reference Group has recommended that environmental water management in 2012-13 should focus on improving resilience of ecosystems and promoting recovery of degraded wetland systems,' says Debbie.

The Macquarie Valley Annual Environmental Watering Plan 2012-13 (120767macquarwp.pdf, 1.8MB) will focus on improving the resilience of 50,000 hectares of semi-permanent wetland vegetation in the Macquarie Marshes, including river red gum woodlands. There will also be a focus on flow requirements to promote native fish habitat and recruitment.

The marshes are the Macquarie River Valley's most extensive wetland asset and in the past have supported some of Australia's largest waterbird breeding events. Water will be set aside to support colonial waterbird breeding, if the need arises.

Debbie says that recent responses to OEH's environmental water delivery have been building with a recent bird survey in the Marshes and adjacent dry areas identifying 146 species at over 50 locations across the 200,000-hectare site.

'Local residents have noted increased numbers of waterbirds foraging in wetland areas. Colonial nesting egrets have also been observed in their breeding plumage. A handful of Australian white ibis have been observed nesting at one lagoon. These signs are not a guarantee that larger scale colonial nesting will proceed. However, they are good initial indications of favourable breeding conditions,' says Debbie.

The ecological character description for the Macquarie Marshes Nature Reserve and U-block components of the Ramsar site has been recently released.

Find out more about environmental water and the Macquarie Valley, including the condition of wetland assets and the Macquarie Valley Annual Environmental Watering Plan 2012-13 (120767macquarwp.pdf, 1.8MB)

Ongoing wetland monitoring has shown that wetland fish communities are recovering and are dominated by native fish species, including the renewed presence of golden perch.

However, thousands of dead mature trees remain, highlighting the severity of the previous dry spell. Native fish populations in the lower reaches of the river have been severely impacted by hypoxic blackwater during successive summer flooding.

The Murrumbidgee Valley Annual Environmental Watering Plan 2012-13 (120764mbidgeewp.pdf, 1.7MB) aims to prevent further decline in distressed wetland vegetation communities, in particular river red gum, black box and lignum communities.

The Murrumbidgee Valley provides habitat for a range of threatened and endangered native fish species. A primary focus for 2012-13 environmental water management is to support native fish breeding and recruitment within the Murrumbidgee River channel.

Wetland-dependent fauna, including threatened species such as the southern bell frog and fishing bat, will also be assisted through environmental water management.

The plan will build on last year's successful delivery of environmental water and significant investment in infrastructure at Paika Lake and Cherax Swamp. This resulted in the foraging and breeding of 35 species of waterbirds and the reinvigoration of struggling fringing river red gums and black box around the lakes. This year water will be delivered to areas further downstream at Hobblers Lake and Penarie Creek, which have not seen water for over 100 years.

Find out more about environmental water and the Murrumbidgee Valley including the condition of wetland assets and the Murrumbidgee Valley Annual Environmental Watering Plan 2012-13 (120764mbidgeewp.pdf, 1.7MB).

The surveys deliberately coincide with the annual Aerial Surveys of Waterbirds in Eastern Australia, conducted by the University of New South Wales.

Now in its 30th year, this long-term wildlife survey covers around one third of Australia.

Data collected through the aerial and ground surveys will provide information on:

• waterbird species diversity, including threatened and/or migratory species where present
• the relative abundance of each waterbird species and breeding activity.

This information is used to track the health of important wetlands over time.

Fundamental to the management of environmental water is knowing when, where and how much of the different parts of a wetland are flooded as a result of environmental water delivery or from natural flood events. In large highly variable wetland ecosystems flooding varies greatly in size over short and long time periods and this can be difficult to measure.

Rachael Thomas from the Water, Wetlands and Coast Science Division says that OEH scientists detect water from Landsat images to accurately map flooding over the large areas of the Macquarie Marshes, Lowbidgee floodplain, wetlands of the Lower Lachlan and Gwydir.

'The variable nature of flooding in inland wetlands has been evident in the last decade, highlighting the importance of satellite imagery and robust techniques to track flood distribution, as a key tool for environmental water managers,' says Rachael.

'Wetland plants and animals depend on a variable flooding regime to complete their life cycles. With a better understanding of flooding patterns over time, together OEH managers and scientists can assess the ecological outcomes of flooding from river flows for improved wetland conservation.'