17/03/2026
Warnings have been issued since 14 March for blue-green algae outbreaks on the Murrumbidgee River between Cooma and Tantangara.
Blue-green algae (cyanobacteria) can affect fish and cause large-scale fish kills. The first stage is when the algae produce toxins that damage fish internal organs and gills, and can cause neurological damage. Then there is a second stage problem when fish start dying from oxygen deprivation as the algae decompose, depleting oxygen in the water, and coating fish gills with scum from the decomposing material.
Fish caught during a blue-green algae outbreak should not be eaten. Anglers who contact the algae can experience rashes, respiratory and gastrointestinal illness. Boiling water does not remove toxins; it may actually release more toxins into the water.
Other native wildlife are similarly affected…birds, yabbies, rakali, platypus, etc. And of course it can be fatal for domestic animals such as sheep, cattle, dogs.
The photo shows the river at Cooma on 17 March, one of the worst visible outbreaks in recent years.
