no. 2 five oaks swamp

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2) "Dri Dri", Mid Western Highway, Gunbar 2711 John Harvey Wetland Management Planning Guide for Five Oaks Swamp Key Objective: To establish Five Oaks Swamp as a shorebird conservation refuge for the Wah Wah region. Key Actions: Increase flooding frequency to once every 2-3 years by delivering water from the No. 10 channel, with approximately 575 megalitres. Timing should coincide with peak shorebird activity between September and April. Maintain existing grazing regime prior to flooding to limit biomass of Canegrass and Lignum on mudflats. Water for Wildlife in the Wah Wah District: planning for the future

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Page 1: No. 2 Five Oaks Swamp

2) "Dri Dri", Mid Western Highway, Gunbar 2711John Harvey

Wetland Management Planning Guide for Five OaksSwamp

Key Objective: To establish Five Oaks Swamp as ashorebird conservation refuge for the Wah Wah region.

Key Actions: Increase flooding frequency to once every 2-3years by delivering water from the No. 10 channel, withapproximately 575 megalitres. Timing should coincide withpeak shorebird activity between September and April.Maintain existing grazing regime prior to flooding to limitbiomass of Canegrass and Lignum on mudflats.

Water forWildlifein the

Wah WahDistrict:

planning forthe future

Page 2: No. 2 Five Oaks Swamp

Context: As part of the AustralianGovernment's water use efficiencyinitiatives, a major infrastructure upgradehas been planned for the Wah Wah district,north of Hay in the New South WalesRiverina. The $44M replacement of openchannels and ground tanks (farm dams)with a pipeline and trough system is set torecover around 9000 megalitres in watersavings per year.Since the 1930s, many wildlife specieshave come to depend on the ground tanks.In 2011 and 2012, a study initiated by thelocal Landcare group began. It assessedthe biodiversity values of Wah Wah'sground tanks and although they wererelatively poor compared to the large,natural wetlands, it found that someprovided important habitat for significantwildlife.Federal Government Caring For OurCountry funding has lead to successulhabitat enhancement trials. These haveincluded earthworks to increase ephemeralshallows and fencing to faciliatate grazingand spelling cycles, all completed with aview to mitigating the future loss of habitatwhen the pipeline replaces the old system.Murrumbidgee Landcare was thensuccessul in seeking funding from theNorman Wettenhall Foundation in 2015 tocapitalise on the momentum and localinterest and extend the work to five keynatural wetlands by developing specificmanagement planning guides with theresepective landholders.The idea is that these guides will provide afirst step in initiating postive managementactions and future resources and funding.These plans are intended to be concise,adaptive, guiding documents, and notonerous in their scope and implementation.Because each of the owners helpeddetermine these management plans anddeveloped their specific objectives, it ishoped there will be a strong sense ofownership moving forward.

John Harvey showing the height ofvegetation in the main stand of Lignumwhich is on the eastern side of Five OakSwamp in November, 2015. An ibisrookery has been recorded severaltimes.

Wah Wah: Water, Wetlands & Wildlife

Five Oaks Swamp provided excellenthabitat for shorebirds, like these Red-necked Avocets and Black-winged Stiltsrecorded in September, 2012.

"Changes to how a wetland is managed,even subtle tweaks, can yield hugebenefits for wildlife, without hinderingagricultural outcomes and often

improving them."

Page 3: No. 2 Five Oaks Swamp

Five Oaks Swamp

Description & History: This wetland isapproximately 230 hectares, depending onthe boundaries used. It's a signficant part ofthe Mirrool Creek floodplain in the WahWah district and one of the largestwetlands in the region. It is presentlydominated by low, regularly grazed standsof Lignum (Muehlenbeckia florulenta) andCanegrass (Eragrostis australasica) but inthe central eastern part of the swamp itsupports taller (>2 metres) Lignum stands.The swamp was part of the original GunbarStation and has an approximately 150-yearhistory of sheep and cattle grazing. Thisremains the primary land use. This swampis part of a ~320 hectare paddock that hastwo ground tanks. The swamp fills from thesouth end when the Mirrool Creek has highflows, like those during the 2011 and 2012floods. With the rare exception of extremelyhigh flows in the Mirrool (approx. 1/30years) when banks are blown out, it nowonly partially fills from run-off aftersubstantial, local rainfall events.

Values:When flooded, supports highwaterbird diversity and abundance,especially shorebirds. An ibis rookery hasbeen observed several times over the past30 years using the tall Lignum stands.In September, 2012, large numbers, atleast several hundred, of Black-winged Stiltand Red-necked Avocet were recorded,together with migratory shorebirds fromRussia, like the Sharp-tailed Sandpiper.The area has also supported FreckledDucks. It has potential to support theglobally endangered Australian PaintedSnipe, which depends on shallow wetlandswith low waterplant cover, as well as theCurlew Sandpiper, which is now consideredcritically endangered within Australia.Migratory shorebirds are undergoing asevere decline. The key driver is thought tobe the loss of mudflats around the YellowSea, but managing some Australianwetlands for these shorebirds can aidglobal conservation efforts along the EastAsian-Australasian Flyway.

Page 4: No. 2 Five Oaks Swamp

Issues: The key issue identified for FiveOaks Swamp relates to the flooding regimeand water supply. Prior to water resourcedevelopment upstream it filled much moreregularly. Altering existing management,such as increased flooding frequency orduration, runs the risk of undoing thehabitat values at this already significantwetland, so careful, ongoing considerationis required. Presently, beyond floodingregimes and water supply, there are nomajor threats to this wetland, althoughgrazing management could could beundertaken more strategically to benefitbiodiversity. Damage from pigs and theimpacts of fox and cat predation on wildlifehave been identified as secondary threats.

Opportunities: Seizing the shorebirdconservation potential of this site. Theswamp has two outlets from the No. 10channel, which could be used to deliverenvironmental water. This channel is notdue to be decommissioned and replacedwith a pipeline.

Key Objective: To establish Five OaksSwamp as a shorebird conservation refugefor the Wah Wah region.

Key Actions: Increase flooding frequencyto once every 2-3 years by delivering waterfrom the No. 10 channel, somewhere in theorder of 575 megalitres (average of 25 cmtotal usage across 230 ha), so that thedeepest areas are wet for between two tosix months and then allowed to completelydry. Timing should coincide with peakshorebird movement between Septemberand April. Initially, maintain existing grazingregime prior to flooding to limitencroachment and biomass of Canegrassand Lignum on mudflats, but avoid grazingwhile wetland is flooded.

Future Considerations: Consider fencingcentral-eastern area with tall Lignum standsto protect ibis rookery habitat. Develop aferal animal control program.

Ackowledgements: Marion Benjamin wassuccessful in seeking Norman WettenhallFoundation funding, while Ian Auldist and MichaelFayle helped select sites, and Karen Jamiesonhelped manage the project. Matt Herring developedthese plans with the respective landholders.

At around 230 hectares, Five OaksSwamp is one of the largest wetlands inthe Wah Wah district.

Monitoring: Photo points and aerialimagery could be used to track anychanges in the extent and structure ofvegetation. Waterbird surveys could alsobe used to help gauge biodiversityresponse and support management thatmaintains the relatively open mudflats,which are central to the existing shorebirdhabitat values.

Implementation and funding strategy:Michael Fayle (Riverina Local LandServices), James Maguire (New SouthWales Office of Environment and Heritage),Erin Lenon (Commonwealth EnvironmentWater Holder) and Karen McCann (MIARenewal Alliance) are all aware of this siteand the opportunity to deliver water andmanage it for shorebird conservation.

Site visits to organise and approve e-waterdelivery could be undertaken prior tospring, 2016. Presently, water is deliveredthrough the Wah Wah stock and domesticsystem in April and October so a springflow is possible. Funding and resources forferal animal control and potential fencingcan be organised as needed withMurrumbidgee Landcare and Riverina LLS.