Bacterial disease cause of mass mortality of fish

Investigators from the Fisheries Department have found ‘Areomonas’ bacteria is the culprit

Hyderabad: Areomonas bacterial infection has been found to be the cause of increased fish mortality in some big lakes and reservoirs during summer. At least eight water bodies are believed to be hit by the bacteria in the recent months.
After Sriram Sagar reservoir was hit in April, some other lakes, including Shamirpet lake and Keesara Pedda Cheruvu in Medchal, are among the water bodies affected by the bacteria.

It triggered massive a number of dead fish being washed ashore. The Fisheries Department is yet to ascertain the loss in monetary terms. The officials, however, ruled out the possibility of effluents, being released into the water bodies, was the cause of bacteria as was suspected earlier.

The officials, who investigated into high mortality of fish during April end and May, found that the fish had fallen prey to the bacteria as the reservoir dried up due to high temperatures. “After the temperature rose and the oxygen content droped, the fish had become susceptible to these kinds of bacteria.

Hence there is more possibility of attack of the infections. Fish deaths due to all these reasons is less than 1 per cent in Telangana State so far and not more than 20 unconfirmed cases,” said a higher official of Fisheries Department.

Amongst the measures suggested by the officials to the fishermen include spraying of lime and oxytetracycline anti-bacterial powder with feed. Even though there were instructions for harvesting before the peak of summer, very few fishermen societies took note of it. Most of the fishermen in big water bodies waited in the hope the size of the fish would increase.

“Partial harvesting and periodic inspection should have been applied, which could have saved the remaining fishes. The more the size of fish, it would be more prone to bacteria and affected by dissolved oxygen,” added the officials.