Trial Watering of Private Wetlands Project
- A Tremendous Success !
In our previous issue of WeDs (#2) the MWWG announced a new and exciting initiative involving eleven wetlands on private properties. Nearly six months later and the Group is very pleased to report on the success of the trial!
In late-2001, the MWWG initiated a pilot project aimed at increasing wetland diversity within the area of operation of Murray Irrigation Limited (MIL). The pilot was part of the MWWG's objectives to develop and implement well-researched, technically sound and community-endorsed management programs for wetlands whilst developing a strategic approach to the management and rehabilitation of wetlands throughout the Murray and Lower Darling catchments within NSW.
"The MWWG identified a need to address wetland degradation in the MIL Area of Operations. This region was once one large floodplain that would only have been connected with the rivers in times of high flows, sometimes not for many years. Due to changes in land-use, draining of wetlands, building of levee banks and irrigation supply channels, these floodplain areas are rarely flooded, not even in times of high rainfall events or high river flows" explained Ms. Trish Alexander, the MWWG Project Officer who conducted the trial's monitoring.
"The majority of the 11 wetlands had not been inundated for periods of up to 20 to 40 years. However, despite this extended 'dry phase' the sites were selected on their existing wetland characteristics and we anticipated that we would see a positive biological response in both vegetation and wildlife if they did receive some water" said Trish.
"All the sites were unique, and included areas such as black-box depressions, prior streams, and lignum swamps."
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Mr. Chris Lahy's property "Uambi", Tullakool - one of the eleven private wetland areas participating in the Trial Watering project - showed a tremendous vegetation response to the trial watering. Week 0 - before water delivery (left) and 15 weeks later (right). Photos courtesy of Trish Alexander.
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Figure 1: Murray Irrigation Limited's Area of Operation,
showing the location of the private wetlands involved in the trial (indicated by a star).
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The MIL Area of Operation is located in central NSW and includes the towns of Deniliquin, Berrigan, Finley and Wakool (Figure 1). The region includes the Murray, Edward, Wakool and Neimur Rivers and their associated floodplains.
With the cooperation from MIL, the delivery of water to the 11 wetlands (total are of approx. 250 ha) was achieved by using MIL's delivery channel system. The water used was part of the 30,000 ML that the MWWG manages on behalf of the NSW Government for environmental purposes.
To detect changes in the vegetation and bird communities throughout the wetting and drying phases of the wetlands, a monitoring programme had been developed by the MWWG, and was conducted by Trish Alexander and Matt Herring (employed by MIL for the project). Various methods were used including photopoints (to monitor broad changes in the wetlands over time), stratified random sampling using quadrats, estimates of vegetation cover/abundance, and 20 minute bird surveys. Monitoring was carried out once every 3 weeks whilst the sites were wet, and a final monitoring session after a period of 9 weeks was done after each individual site had dried.
Some of the key outcomes from the trial include:
- Increased abundance in wetland plants such as reeds (Juncus spp.), rushes (Eleocharis spp.), nardoo (Marsilea spp.).
- Regeneration of wetland plants from the existing seed bank, including water ribbons (Triglochin spp.), starfruit (Damasonium minus), and water milfoil (Myriophyllum spp.).
- Black box trees at all sites exhibited signs of new growth, and some flowered.
- Improved landholder knowledge and understanding of wetlands and the benefits of delivering water to these formerly dry sites.
"There were many positive responses detected through this project. The improved health of the trees within these wetlands was obvious. Trees started to produce new growth, and some started to flower. This leads to the possibility of seed being dropped and, with the residual moisture in the soil, regeneration may occur" explained Trish.
"The increase in abundance of plants that were already present, and the emergence of new plants at the wetlands after they received water was remarkable! Some plants had a 100% increase in abundance. Finding plants that were not detectable prior to watering, and that were quite abundant after inundation, was one of the most positive results of this project. It gives a good indication of the resilience of wetland plants and gives us the knowledge that the seedbank of these plants and others will be renewed."
The results of this trial watering also found that as the period of inundation increased, so too did the number of wetland plant species (in number and abundance). In addition was the interesting result that numbers of introduced plant species declined whilst native terrestrial plant species were relatively unaffected by the duration of inundation.
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Photopoints of the wetland area on Susan & Neil Bull's property "Union Plain", Deniliquin. Week 0 - before water delivery (left) and 12 weeks later (right). Photos courtesy of Trish Alexander.
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The response in bird communities was also positive with a total of 140 species recorded during the six months of monitoring. At most of the sites bird species diversity, comprised of waterbirds, shorebirds, and woodland birds, increased after inundation. The vast majority of waterbirds were observed foraging in shallow open areas, mudflats were found to exclusively support resident and migratory shorebirds such as Latham's Snipe and Black-fronted Plovers; and Black-tailed Native Hens occupied the Lignum bushes at the water's edge. Woodland bird observations included species considered to be in decline such as the Red-capped Robin, Chestnut-rumped Thornbill and Jacky Winter.
A total of 9 bird species recorded are listed under the NSW Threatened Species Conservation Act, and of these, 4 are also considered threatened species under national legislation.
"The project has provided an important benchmark for the sites involved and generated useful data on initial avian responses to environmental flows" Trish said.
Apart from the terrific biological response observed, the reaction from landholders was also extremely positive. All landholders were pleased to see the health of their trees improve and were surprised at the diversity of plants that emerged from the soil. Many did not realise that their sites supported the different kinds of wetland plants that 'appeared' after being dry for 20 to 30 years.
Susan and Neil Bull of Deniliquin (pictured below) are two of the landholders whose wetland was chosen for the trial, and have been very happy with the results on their property.
"We should have done this years ago" Susan said. "It's absolutely beautiful down there. The trees look great. We are so pleased with it all!"
Being keen bird observers the Bull's were also thrilled with the birdlife response that they saw on their property, "What has struck us with great force is the contrast with the flow of Box Creek. At very best you might see between 2 and 6 ducks. In our small wetland there are hundreds of birds, representing a wide variety of species. We are pleased to have maintained our bush birds, as well as gaining the water birds."
With such an overwhelming success the MWWG is looking at repeating the project for the coming summer.
Many thanks must go to all the participating landholders - Linda & Donald Barclay, Susan & Neil Bull, Lyndall & Peter Horne, Lorraine & Brian Hopper, Michelle & Alan Jones, Chris Lahy, Kerry & Nick Lowing, (the late) Nol Neesom & Family, Ken Prowse and Meredith & Lachlan Stevenson; the Board and staff of Murray Irrigation Limited, especially Jenny McLeod, George Warne, Chris Shaw & Peter King; and John Naimo & Jack Chubb (DLWC) for their assistance and cooperation throughout the project.
Message from the Chairman
"Many community groups like ours are facing an uncertain future with the ending of NHT funding as we have known it for the past few years. Wetland rehabilitation projects often take longer than anticipated and require a great deal of time and effort - and in particular, they need Project Officers to drive them. Of course the world changes and plans have to be modified, but the fact remains that without funds for staffing, our Group's activities would simply stop. So the struggle to maintain staffing levels will continue, as the framework for allocating funds takes on a new direction. We will strive to continue to do our work to the best of our abilities and hope the importance of healthy riverine and wetland environments remains a high priority within the community.
"Now that NHT funding is to be more directed towards Catchment Management Board priorities, an issue for our Group is to consider when it should accept lead roles in projects that are not necessarily considered core activity by us or the Boards. We must be careful of over extending ourselves with limited resources, but we still need to encourage cooperative projects with other community groups and agencies. One example of a very successful cooperative project is the partnership the Group has developed with the MDBC to continue the Commence-to-Flow and Wetlands Database within the Murray Region. This project is leading the way in providing essential information for environmental flows within the region and will assist other community groups such as Catchment Boards on both sides of the border. Hopefully, with the recently announced increased government funding for fishways and the move towards manipulating weir pool levels, there will now also be a more strategic approach to solving some of the major riverine issues which also affect the riverine wetlands.
"Finally, the 'Trial Watering of Wetlands on Private Properties' project has been a fundamental success. The way forward now is to determine how much interest and commitment to the project is out there, and how our staff levels can cope with demand to oversee this exercise. I believe we can achieve much in promoting our aims, and wetlands in general, through engaging others in this exercise." - Howard Jones
Major Projects Round-up
The MWWG is currently involved in a number of differing projects. Listed below are a few of the major projects and information on their progress:
Commence-to-Flow Project:
- Project Officer Damian Green has been working on a consultancy with the Murray-Darling Basin Commission's (MDBC) Environmental Flows team. The consultancy is looking at how the River Murray Wetland Database can assist with modelling.
- The MWWG has received funding from the MDBC, which will enable the project to further develop.
- The appointment of a Project Officer, for the project's second phase, is expected to be finalised within the next month.
Trial Watering on Private Wetlands:
- Monitoring has finished and a draft final report has been completed.
- The project was deemed very successful both on a biological response level and as an education/engagement tool for participating landholders.
Stevens Weir Fishway:
- Delays are expected to continue until it is determined whether or not a hydroelectric scheme will proceed at the weir.
Wetland Monitoring Kit:
- A final draft has been completed.
- The Department of Land & Water Conservation (DLWC) has offered funding to cover printing costs of the kit.
Thegoa Lagoon:
- The implementation of Thegoa Lagoon Management Plan is being pursued. A review of all stakeholders commitment to the Plan is to be conducted.
Bottle Bend Billabong:
- Surveys focussing on the aquatic fauna and vegetation have been organised to collect baseline data and to provide management recommendations for the billabong (located within the Gol Gol State Forest).
- Two piezometers have been installed near the billabong to gauge the influence of the Mildura Weir Pool on the groundwater movement into and under the billabong.
Wetland Mapping Within the Murray Catchment
The 'Wetland Mapping within the Murray Catchment' project is one of the MWWG's projects that has been steadily progressing - and has so far identified over 1000 wetlands!
The project was designed by the MWWG, in conjunction with the Murray Catchment Nature Conservation Working Group Inc., to collect baseline information on the number of wetlands, their size and condition within the Billabong Creek and Upper Murray catchments. The project began in 2000, after being contracted to Ecosurveys Pty. Ltd, and is funded through the State Wetland Advisory Committee (SWAC).
With an overall objective to map all wetlands within the Billabong Creek and the Murray River (upstream of Hume Dam) catchments, there are four main aims to the project:
- map and develop an inventory of wetlands 1 ha or greater in size;
- assess the hydrology, geomorphology, vegetation and condition of each wetland;
- provide adequate information for assessing the rehabilitation potential of these wetlands and developing priorities for wetland rehabilitation; and
- develop a GIS database of wetlands for each of the specified catchments.
Using aerial photography, over 700 wetlands have been identified in the Billabong Creek catchment (from the headwaters east of Holbrook downstream to Moulamein) and approximately 320 wetlands in the Upper Murray catchment. The majority of identified wetlands have their own data sheet recording information such as land use, wetland classification, impacts (eg: salinity, clearing, fire, grazing etc.), water control/storage structures, faunal and floral observations and the overall condition of the wetland. After the wetland's boundaries have been established this information is then transferred to topographic maps with scales of either 1:25,000 or 1:50,000.
Commenting on the data collected to date, Project Manager Mr. Rick Webster said, "So far we have identified over 1000 wetlands within these catchments - and this does not include those wetlands that are within areas managed by either NSW State Forests or the NSW National Parks and Wildlife Service. Within the Central Billabong Creek area, which stretches from Walbundrie to Jerilderie, we have identified 187 wetlands and in each of the Upper Billabong (upstream of Walbundrie) and Western Billabong (Jerilderie to Moulamein) reaches there are approximately 300 wetlands.
"The information gathered from this project will enable the MWWG to develop and prioritise strategic rehabilitation projects within the catchments. After completing on-ground assessments for 43% of the wetlands in the Central Billabong reach, we have determined that the majority of these have suffered from only minor to moderate disturbance - and only 8% fall into the 'extreme disturbance' Wetland Condition category. This is encouraging as it suggests a lot of these wetlands have the potential of being rehabilitated.
"We still have some work to do before the project is completed. The next step is to finalise the databases for each of the catchments which will then enable us to commence the analysis of the data on the wetland information gathered. The analysis will include a summary of the main features of the wetlands such as geomorphology, hydrology, Ramsar classification, dominant vegetation community, land use and site impacts and wetland condition. If all goes to plan the project should be completed sometime next year."
MWWG Membership Changes
The MWWG would like to welcome Ms. Alison King (left) who is the new NSW Fisheries representative replacing Ms. Michelle Perry. As the Conservation Manager for the Murray Region, based in Albury, Alison's expertise lies in fish recruitment and freshwater ecology.
As mentioned above the Group has lost from its committee Ms. Michelle Perry (NSW Fisheries), as well as Dr. Stuart Blanch (Australian Conservation Foundation) and Mr. Daryl McGregor (Murray CMB & Albury City Council) from its committee. The Group would like to thank all three for their contributions and wish them all the best for future pursuits.
Progress on Fishways Project
The Murray-Darling Basin Commission (MDBC) have begun investigations into the construction of fishways at Locks 7, 8, 9 and 10 (Wentworth) on the Murray River.
As part of the Commission's 'Basin Sustainability Plan' the Fishway Program is aimed at re-establishing migratory pathways of native fish from the 'Murray Mouth' to Lake Hume, and thereby reducing the decline in the distribution and abundance of native fish species.
In March a workshop was held to discuss issues associated with the installation of the fishways. Scientists, natural resource agency and environmental group representatives were all in attendance to discuss the most appropriate fishway design for each lock, as well the range of weir pool levels within which the fishways should be operational.
The Fishway Program has begun at Locks 7 and 8. It will next proceed to Locks 9 and 10 and then onto Locks 1, 2, 3, 4, 5, and 6. Lock 15 (Euston weir) is anticipated to have a fishway structure constructed that will be similar to that at Deniliquin as an interim measure, with the possibility of a vertical slot fishway being installed at a later date.
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Art work and joke by Victoria Palmer, Wentworth, NSW.
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