Lampreys are an eel-like fish. They spend most of their life at sea, but migrate into rivers to spawn.
Lamprey numbers in the Murray–Darling Basin have declined because of barriers to migration and reduced river flows.
Keeping the ocean and Basin rivers connected is crucial to lamprey survival.
What are lamprey?
Lampreys are an ancient, eel-like jawless fish.
Lampreys are usually anadromous fishes, meaning they swim up rivers from the sea to lay their eggs. After hatching, young lampreys move back down the river to the sea.
Lamprey can migrate up to 2,000 kilometres between the ocean and River Murray to breed!
Lampreys are most active during the night and burrow into the stream bed at other times. This makes it difficult to determine their exact breeding locations.
Lamprey and water for the environment
The 2001-2009 Millennium Drought saw many fish suffer in the Basin, including lamprey. The drought prevented them from migrating upstream and completing their breeding cycle.
Because of this, only one short-headed lamprey was detected between 2007 and 2018.
Water is often extracted from the river to support towns, farming and industry. In these dry times, water for the environment keeps the river system healthy and flowing.
Water for the environment has kept the Murray River connected with the Coorong for more than 10 years. This has driven a gradual and significant increase in lamprey numbers.
In 2020, we detected a record number of lamprey, including 101 pouched and 3 short-headed lamprey.
Pouched lamprey (top) and short-headed lamprey (below). Photo: Tracey Steggles
Monitoring lamprey populations
Monitoring informs how we can deliver water to support lamprey.
We track lamprey as they move through the fishways along the River Murray. They're often microchipped to track their movement and spawning behaviour.
The Living Murray program funds lamprey monitoring. This is a joint initiative coordinated by the Murray–Darling Basin Authority, involving state and Commonwealth government agencies.
Monitoring is also undertaken by:
- South Australian Research and Development Institute
- SA Water
- CSIRO.
Together, this knowledge, research and data helps us target flows, support lamprey recovery.