How do you know if you nail something?
For the Murraylands and Riverland Landscape Board Wetlands Team, that is a relatively easy question to answer.
Posted 04 May 2021.
Murraylands and Riverland Landscape Board Wetland Team Leader Darren Willis says take a look at the water clarity in the image.
“This is what it looks like when you carefully manage a pool connected wetland.”
“We use wetting and drying cycles to consolidate the wetland soil bed and then slowly refill the wetland.
“By slowly refilling the wetland, we minimise stirring up the sediments and keep the water clearer.
“We also add a well-designed carp exclusion screen which prevents the large fish from getting back into the wetland.
“The result – crystal clear water with incredible aquatic habitat development.
Mr Willis said nearly every part of the ecosystem benefits from this management and achievement.
“From old trees, regenerating trees and understory, aquatic plants and their seeds, spores and microbes, to macroinvertebrates, fish, frogs, turtles and birds.
“Eventually, the small carp that get through the exclusion screen will grow and begin to impact the condition of the wetland and ultimately, they will start turning it back into a murky pool.
“Then the Wetlands Team will dry the site out and refill it, so the cycle starts again.
“But in the meantime, this is an incredible example of what we can do and how our managed wetland environments respond when you remove carp from the environment and add water.
“Ongoing refined wetland management and environmental watering technique trials are a crucial part of the work undertaken through the Board’s Wetlands Program.
“We also share our knowledge and experience with partner organisations across the Murray-Darling Basin.
Over the next few years, the Wetlands Team will be conducting trials to reduce the impact of large carp in our managed wetlands using water delivery techniques that have recently shown some real promise.
“The focus will be on improving the performance of carp ‘screening’ methods to increase and extend the duration of the fantastic aquatic habitat conditions that we’ve been able to achieve.”
Mr Willis said the ultimate test of our success in this work will be the ability to re-introduce threatened native wetland fish species, such as the Southern purple-spotted gudgeon (Mogurnda adspersa), back into ‘wild’ sites along the River Murray in South Australia.
This project is supported by the Murraylands and Riverland Landscape Board through funding from the Australian Government’s National Landcare Program and the landscape levies.