Native fish need to move long distances to spawn. The Murray-Darling Basin Commission is installing fish ladders to help native fish move past weirs. Some weirs are removed during times of known fish migration. Major storage dams sometimes give out too little water for suitable fish habitats. Flows of water are increased to benefit native fish.
More research is needed to find out what pollutants actively attack native fish.
River managers try to stop the discharge of toxic wastes into the river. Native fish numbers in the Murray-Darling river system are falling rapidly. Restrictions may have to be put on commercial and recreational fishermen. Limits on fishing have already been imposed in South Australia with a temporary ban on catching Murray Cod and a bag limit on the number of Golden Perch caught.