Thousands of snails pile up on Madiwala Lake banks in southeast Bengaluru

BENGALURU; Thousands of left whirl shell snails have accumulated on the banks of Madiwala Lake in southeast Bengaluru, triggering concern among walkers and residents, who claim that many of them are dead.
While residents said the snails had paid the price for the waterbody’s rising pollution, the forest department — custodian of the lake — allayed their fears by saying their death is a natural phenomenon.

Rajesh HG, a long-time resident of BTM Layout, said they had seen dead snails on the banks over the past 10 days. “On Wednesday morning, thousands of them could be spotted on the lake shore. I have been living in the vicinity for two decades and have never witnessed something like this. Dead snails point to rising pollution levels in the lake, which is one of the largest waterbodies in the city,” he added. Prakash PM, a resident of Madiwala, said: “Sewage entering the lake from a nearby storm water drain is to blame.”

Syed Nizamuddin, range forest officer (KR Puram), Bengaluru Urban forest division, however, begged to differ. “It is a natural phenomenon. During this time of the year, fresh water molluscs gather on the lakeside for reproduction. While new ones survive, many old ones die. While it’s true that sewage has entered the lake following heavy rain in the past few days, there’s no reason to panic,” he said.

Snails are one of classes of freshwater molluscs.

Another resident of Madiwala said she’s also seen dead fish in the lake. “Migratory birds are also perishing. However, the authorities are quick to remove the dead fish and birds. But the large number of molluscs is indicative of the damage caused to the waterbody,” she added.

Madiwala Lake, also known as BTM Lake, is said to be 300 years old. Legend has it that the lake, spread over 115 acres, was built by the Cholas overnight with hundreds of workers put on the job. It’s water was fit for drinking till the early 1990s. Due to industrial waste and sewage entering the waterbody, it gradually became polluted. Spot-billed pelicans are among the regular avian guest at the lake.