Several fish and spot-billed pelicans were found dead at Harohalli Lake in northern Bengaluru between December 24 and 26, alarming nearby residents who suspect pollution. Officials from North City Corporation and aquatic experts say the deaths may be due to a sudden drop in temperature. V. Ramprasad of Friends of Lakes noted a similar event near Bengaluru last month and suggested a viral infection might be involved. Residents like Bindu spotted dead fish near the lake edges, while G. Selvarajan from Green Circle reported 12 dead fish and two pelicans on December 25. He also raised concerns about untreated sewage discharge because of nearby apartment developments. North City Corporation Commissioner Pommala Sunil Kumar said officials inspected the site and that the lake engineers point to temperature-related causes but will conduct tests to confirm. Aquatic biology expert Dr. Shivakumar Magada explained that fish deaths often occur during sudden weather changes. The recent big temperature drop in Bengaluru, with readings as low as 13.6°C on December 22, likely pushed fish deeper and upset oxygen levels underwater, causing the deaths. Commissioner Kumar confirmed receiving similar complaints from residents and assured that the issue will be thoroughly examined. The cause could be temperature shifts, pollution, or a combination, and authorities are monitoring the situation closely.