Dead fish, pelicans found at Harohalli lake

Several fish and spot-billed pelicans were found dead at Harohalli Lake in the northern part of the city between December 24 and 26, alarming nearby residents, who suspect that pollutants may have entered the waterbody.

However, officials of the North City Corporation and limnologists suggested that the deaths could be due to a drop in temperature in the city.

V. Ramprasad of Friends of Lakes pointed out that a similar incident occurred at a lake on the outskirts of Bengaluru about a month ago, where both pelicans and fish were found dead. He said the deaths could also be the result of a viral infection and stressed that the development should not be ignored.

A dead fish at Harohalli lake in Bengaluru.
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The officials too have not ruled out the possibility of the fish deaths being linked to the pelicans.

Bindu, a nearby resident and regular walker, said she spotted three dead fish on Friday. However, G. Selvarajan, chairman of Green Circle, told The Hindu that 12 dead fish were found on December 25.

“All the fish were found dead along the edges of the lake, and there may be more in the middle. We also spotted two dead pelicans, which raises suspicion about the discharge of untreated sewage and pollutants,” he said, adding that several apartment complexes have come up in the neighbourhood.

Site inspected

North City Corporation Commissioner Pommala Sunil Kumar told The Hindu that officials had inspected the site and that the corporation’s lake engineers suggested the deaths might be due to a drop in temperature. “It could be temperature-related, but we will look into it and conduct tests to ascertain the cause,” Mr. Kumar said.

Shivakumar Magada, limnologist and professor of aquatic biology at the College of Fisheries, Mangaluru, explained that fish deaths in waterbodies are common during the onset of monsoon and summer. However, in this case, he said it could be due to a significant drop in temperature.

“During the onset of the monsoon, such incidents are very common, as sudden downpours can lead to fish deaths. This year, temperatures have dropped substantially in Bengaluru, pushing fish into deeper waters and causing fluctuations in oxygen levels,” he explained. “An unfavourable condition at the bottom of the waterbody, which disrupts oxygen levels, may have caused the deaths,” he added.

Plummeting temperature

Notably, the Bengaluru KIAL observatory recorded a temperature of 13.6 degrees Celsius on December 22, followed by 14 degrees Celsius on December 23 and 24.

The corporation Commissioner echoed Mr. Magada’s observations and reiterated that the issue would be examined. “I have received similar complaints regarding pelican deaths from Residents’ Welfare Associations. We will look into the issue,” he said.