Lampreys are on the move!
South Australia’s favourite toothy fish, the lamprey, are on the move!
Eleven pouched lamprey (Geotria australis) were trapped and tagged at the Goolwa barrage fishways in August and recently, the progress of one of these determined explorers has been tracked passing Lock 10 at Wentworth in New South Wales. That is a casual journey of 825 km over 2 months, which is no small feat for a 50 cm fish!
With water for the environment flowing to South Australia this spring, and so many of the River Murray’s tributaries still flowing strongly, the conditions are ideal for lamprey migration across the southern Murray-Darling Basin. According to the Department for Environment and Water’s (DEW) Program Leader, Coorong, Lower Lakes and Murray Mouth, Adrienne Rumbelow, lamprey are benefitting from the conditions, which have rarely been seen in the river since before the Millennium Drought.
“Lampreys are a rare and primitive fish that migrate upstream from the Southern Ocean to spawning grounds in the River Murray and its tributaries” Ms Rumbelow said.
“Thanks to allocations of water for the environment, as well as the construction of fishways at barrages and weirs, we’re now seeing more lamprey on the move as they migrate upstream to breed.
Monitoring of fishway traps at the Lower Murray barrages by the Department of Primary Industries and Regions SA’s (PIRSA) South Australian Research and Development Institute (SARDI) has enabled lamprey to be caught when passing from saltwater to freshwater. Once caught, they are tagged and released so that their onward migration can be monitored.
Water for the environment, delivered to the Coorong and Lower Lakes in winter and spring, is contributing to increased numbers of these ancient and mysterious fish., with The growing numbers reflecting the slow recovery of the River Murray’s ecology, especially for those native fish that require freshwater flow and connectivity between the river and the sea.
Lamprey monitoring is conducted by SARDI Aquatic Sciences with the assistance of SA Water. Monitoring is funded by The Living Murray, a joint initiative funded by the New South Wales, Victorian, South Australian and Commonwealth governments, coordinated by the Murray–Darling Basin Authority.