Awash with new life
Thousands of seedlings have been planted around the Aldinga Washpool Lagoon by a team of people dedicated to restoring the site for the betterment of native flora and fauna.
The five-year Aldinga Washpool Revegetation Project by Green Adelaide and the City of Onkaparinga around the Aldinga Washpool Lagoon is approaching its halfway point and is already enjoying significant results.
The project recognises the importance of the ecology of the site and the cultural and spiritual significance of the land to the Kaurna community. The washpool is one of the last remaining freshwater coastal and estuarine lagoon systems in metropolitan Adelaide.
Council’s Coast and Estuary Technical Officer Kerri Bartley explains that in this second year of the project the focus has been on improving the self-sufficiency of the wetland. A ‘no regrets’ restoration plan was agreed on by the six different land tenures within the washpool, meaning there would be no major changes made to the site, only replenishing what is already there.
The washpool is home to more than 80 species of native plants, including 20 plant species that are rare, vulnerable or endangered in the region. Local Kaurna business Aboriginal Contemporary Arts (ACA) Studios planted 15,500 seedlings around the main water body, bringing the total of new plantings to more than 27,000 seedlings so far planted in the washpool. In the primary dune, Kaurna monitors have overseen the planting of 800 seedlings including rare species like Leucopogon, a shrub in the Ericaceae family, and Lachnagrostis, a member of the grass family.
“Working with local Kaurna people on country to protect the many species of rare plants has been one of the most significant aspects of this project,” Kerri says.
Regenerating native plant species and encouraging their spread into the wider area around the washpool is helping to re-establish habitat and outcompete woody weeds like olives and boxthorns, as well as smaller herbaceous weeds that have crept in.
To aid the establishment of the new seedlings, council has been trialling new types of environmentally friendly cardboard guards.
“Council has pledged to stop using plastic guards because of their environmental impacts including the risk of them blowing off in storms and ending up in waterways,” Kerri says.
“The cardboard guards being trialled around the washpool are compostable, meaning they will completely break down if they do go into the lagoon or creek. We are pleased to make this contribution to mitigating microplastics in the washpool.”
Friends of Aldinga Scrub and members of Youth and Community in Conservation Action (YACCA) joined Green Adelaide and council staff in a working bee to assemble the guards, walk them out to the washpool and install them around the plants.
The efforts of the groups involved in the revegetation work are being rewarded, with several fauna species appearing in greater numbers. Intensive replanting of Gahnia filum, or Thatching Grass, has allowed for the successful reintroduction of the Yellowish Sedge Skipper butterfly, whose caterpillar feeds solely on the plant. Habitat loss and spraying of insecticide preceding the late 1980s had eradicated the species from coastal wetland habitats on the Adelaide Plains.
“It has been wonderful to see the butterfly return to our region,” Kerri says.
Early this year, council team members, volunteers and staff from Green Adelaide collected and successfully raised 100 of the butterfly pupae. The pupae were stored safely in individual containers and were released into the washpool as they emerged.
“The butterflies we released in April are successfully breeding now. We have seen larvae in shelters on the new Gahnia filum growth,” Kerri says. An additional brood of pupae were collected to aid repopulating of the butterfly and were released during the second week of spring.
“The main goal of everyone involved is to make the washpool a sanctuary for the waterbirds and create habitat for breeding and refuge,” Kerri says. “More than 180 species of birds have been counted in the washpool, including migratory birds that fly in each year from Russia.”
To the delight of the washpool caretakers, Pied Stilts have been seen nesting in the lagoon area, and a pair of threatened Hooded Plovers have just nested on the pebble bank in front of the lagoon.
Washpool caretakers (from left) Matt Endacott (Green Adelaide), Danny Millbanks (City of Port Adelaide Enfield), Tony Flaherty (Green Adelaide), Kerri Bartley (City of Onkaparinga), Jean Tucker (BirdLife Australia) and Julie Burgher (Friends of Aldinga Scrub); releasing a new brood of Yellowish Sedge Skipper butterfly pupae to repopulate the species.