TWE treasures water with 15 years of support for wetland biodiversity
On World Water Day, Treasury Wine Estates marks its contribution to regional biodiversity with the 15th year of its wetland rejuvenation project at Markaranka vineyard.
The initiative delivers environmental water to the 200-hectare wetland in South Australia’s Riverland region, creating an abundance of breeding activity for vulnerable and threatened species including the Southern bell frog and regent parrot. The targeted water delivery program has also led to stronger, healthier canopies in black box trees and river red gums, including some trees that are hundreds of years old, as well as seed germination for a range of local tree species.
A collaboration between the Murraylands and Riverland Landscape Board, the Commonwealth Environmental Water Office and Treasury Wine Estates, the project bolsters wetland and floodplain health by simulating the regular wetting-drying cycle that wetland ecosystems relyon. We have donated 795 megalitres of water since the program started in 2009, as well as providing technical support and maintenance through our localvineyard team.
Treasury Wine Estates’ Global Director of Sustainability, Michael Parks, said improving biodiversity was apriority for the company, which recently released its inaugural water strategy, Treasuring Water: “As an agricultural business at heart, we’re focused on cultivating a better future – including boosting biodiversity and ecosystem health in the regions where we operate. Markaranka is an ecologically significant wetland complex, and we’re proud to be helping create the right conditions for local flora and fauna to thrive. We’re all custodians of our natural environment, and protecting it for future generations is part of our ambition to lead the industry in sustainability.”
The 2022-23 flood gave the whole wetland complex a great boost. However, the lack of regular high flows in between natural floods means these good outcomes are not maintained and long-lived trees, such as the river red gum, can quickly become stressed in dry years. The Markaranka Wetland Complex is one of several sites in the South Australian Murray Darling Basin that receives environmental water to boost wetland and floodplain health in between flood years. Flows in the River Murray need to reach 70,000 megalitres of water a day to naturally inundate the site. Without this water, wetland floodplain health is compromised, which in turn impacts breeding habitats for water-dependent plants and animals including fish, frogs, turtles, and birds. The number of bird nests, including cormorant and darter species, has significantly increased since the influx of water and improved conditions of prime nesting trees across the basin.
Wetlands Ecologists, Annie Kriesl and Steph Robinson, with the Murraylands and Riverland Landscape Board, observed wetlands that are in good health before a flood comes provide far greater shelter, food and breeding opportunities than a floodplain in poor condition: “healthy tree canopy, lush lignum shrublands and a diverse array of plants supported so much wildlife at Markaranka during environmental watering events and during the flood. It was a contrast to floodplains that were highly stressed from a lack of water” said Annie.
Steph described delivering water via pumping to wetlands in between floods has other benefits. “The environmental watering project at Markaranka created wetlands free from the invasive common carp. The water was crystal clear allowing aquatic plants to grow. Frogs started calling as soon as the pump started and once water levels started to reach fringing vegetation, it was a full-blown cacophony. With prime habitat that’s free of predators, many water-dependent plants and animals have a much greater success rate: it’s just one piece of the puzzle to build biodiversity in the region.”
The main lagoon of the complex will now undergo a dry phase, an important part of the wetlands hydrological cycle. Positive ecological outcomes are expected to continue including supporting the growth of germinated seedlings and allowing plants to colonise the wetland bed, ready to provide areas for water-dependant animals to breed when watering recommences in the coming season.