In a bid to regenerate Acacia rhetinocarpa a two hectare area of Ferries McDonald Conservation Park at Monarto was burnt last week during an ecological prescribed burn carried out by the Department of Environment Water and Natural Resources (DEWNR).
The plant targeted in the burn is a resin wattle, listed as vulnerable nationally, is a species endemic to SA.
Natural Resources SA Murray-Darling Basin (SAMDB) Restoration Ecologist Kylie Moritz said while it seemed unusual to burn a vulnerable species the aim behind the prescribed burn was to asses how the resin wattle would respond to a spring fire.
“In autumn 2015 Natural Resources SAMDB surveyed all populations of resin wattle in the SAMDB region and found their numbers had declined significantly,” she said.
“Not only were there fewer plants, but many of the populations contained plants that were old and dying.
“There was also very little recruitment of new plants and this raised concerns about the future prospects for resin wattle in the region.
“The small population at Ferries McDonald Conservation Park was the chosen site for the ecological burn as it contained more than 300 plants in 2008, but only 90 in 2015, and a number of the remaining plants were showing signs of deterioration and old age.
“Like a lot of wattles, resin wattle responds well to disturbance.”
Ms Moritz said in places where this species is found, resin wattle seedlings are coming up in disturbed ground such as when a new fence line is put in or a service line is installed in roadside vegetation.
“We have also seen recruitment of seedlings in areas where animals, such as echidnas, are moving soil and seed around,” she said.
Within the SAMDB region populations are known to occur around Murray Bridge, Brinkley, Monarto and Finniss areas.
“The Brinkley area contains the highest number of resin wattles, with approximately 400 plants at Monarto Conservation Park and 650 plants at Ferries McDonald Conservation Park,” Ms Moritz said.
The resin wattles at Monarto Conservation Park were planted more than 10 years ago and are part of a University PhD study.
Natural Resources SAMDB is working with a number of landholders and local councils to manage threats to resin wattle populations including grazing pressures and weed management.
Natural Resources SAMDB hoped this ecological prescribed burn may provide insight into the use of fire as a management tool to better secure the future of the species.
This project is supported by the SAMDB Natural Resources Management Board through funding from the Australian Government’s National Landcare Programme and NRM levies and the Department of Environment, Water and Natural Resources.
If you would like more information about this species, please contact Natural Resources Centre Mount Barker on phone 8391 7500.