After finding dead fish floating on water, the PMC administration woke up on Friday to tackle the situation. “Preliminary inquiry indicates the death is due to lack of oxygen. This is due to water hyacinth covering the lake,” said M K Nighoj, the vet at Rajiv Gandhi Zoological Park in Katraj.
He said the shortfall in rain was the reason the water hyacinth did not shift from the lake and continued to grew there.
“The PMC health department has the responsibility of removing water hyacinth from water bodies, but the work was delayed due to focus on tackling dengue,” Nigoj said, adding that increase in fish population and decrease in oxygen levels most likely created this situation.
In the past, there was a controversy over allowing tourist boating on Katraj lake. The death of a tourist made the PMC to stop boating activities carried out by the Maharashtra Tourism Development Corporation.
There was also controversy on allowing fishing in the lake. A crocodile ended that. Although there were no reports of any attack on fishermen the crocodile was spotted by many and a search was conducted for days. The crocodile was not found but not wanting to take any risk, the PMC stopped fishing activity too.
PMC activist Sarang Yadwadkar said the death of fish in Katraj lake was shocking and the reason should be investigated. “There is a possibility that dissolved oxygen in water has dropped owing to hyacinth. However, the dead fish raises various questions. To find answers, laboratory test of water sample should be conducted,” he added.
“Water hyacinth does not grow all of a sudden,” Yadwadkar said, adding it was the responsibility of PMC to remove it but they failed to do so.
PMC environment officer Mangesh Dighe said the administration will send water samples for lab tests to ascertain oxygen content. “If large number of fish died in a small span of time, it needs to be investigated properly. We will also approach the state fisheries department to find the reasons,” he added.