Environmentalists and guardians of the Kerala’s biodiversity have reasons to worry on this World Environment Day as massive fish kills continue to be reported from various parts of the State.

Incidents of dead fishes washing up on the banks of Chalakudy River on two successive days from May 29 are the latest in the list. It has raised alarm among the public about pollution and its effect on marine wealth.

A hartal in protest against fish kills was held in seven panchayats — four panchayats in Thrissur and three in Ernakulam– that share the banks of the Chalakudy River on Tuesday.

“Pollution of water bodies caused by pollutants, including sewage, has led to the decline of oxygen level. Our district coordinator has reported that this was supposed to be the reason behind fish kills reported from Chalakudy River as well. We will be writing to the agencies concerned besides holding a study into the reasons for fish-kills reported in the State,” K.P. Laladas, member-secretary, Kerala State Bio-diversity Board, told The Hindu.

K.G. Padmakumar, former Assistant Director of the Regional Research Centre, Kumarakom, Kerala Agriculture University, said the initial days of the monsoon were crucial for maintaining fish wealth.

“It is the breeding period for fish species and as they come up to the surface of the water they will be exposed to all sorts of pollutants that will be flushed into the river in rain. The monsoon after a severe drought-like condition, as the one experienced by the State this year, when rivers go dry is all the more critical. Besides, unscientific and outright dangerous methods of fishing like passing electric current and poisoning the water also affect the fish wealth,” he said.

Repeated pleas to authorities concerned to be extra vigilant during the start of the monsoon to protect fish species have fallen on deaf ears. “What we need is dedicated environmental policing and courts to settle environmental issues.

The NGIL Action Council that had called for the hartal has alleged that discharge of toxic industrial waste by the Nitta Gelatin India Limited (NGIL), an Indo-Japanese industrial venture along the banks of the Chalakudy River in Kadukutty panchayat in Thrissur, was behind fish kills.

“We have been demanding the closure of the company for polluting river. About five tonnes of fishes were dead in recent incidents and many species are likely to become extinct in the river. The company, which has been using up lakhs of litres of water from the river for its production purposes was polluting the same river by discharging industrial effluents,” said K.M. Anil Kumar, convener of the Action Council, while warning sustained campaign for the closure of the company.

G. Susheelan, managing director, NGIL, however, refuted this allegation. He said that the company had been discharging treated water to the river for the last 35 years of its operations and cannot be held responsible for the recent isolated incidents.

“Fish kills were reported four-and-a-half kilometre and seven kilometres downstream of the company’s discharge point. Fish-kills, however, were concentrated in two points and not all along the stretch of the river from the discharge point, which should have been the case if we were responsible. So something has happened at those two points and there should be a thorough investigation to reveal it,” he said.

Meanwhile, the Ernakulam district fisheries department, which had collected water samples from within the limits of the district and got it tested at the fisheries college at Panangad, has found high pH and ammonia content level that could prove toxic to the flora and fauna. “Besides, the nitrate level also was on the higher side. We have submitted reports to Thrissur and Ernakulam district collectors,” said M.S. Saju, Deputy Director, Fisheries, Ernakulam.

Interestingly, the Pollution Control Board officials in Thrissur have found the pH and biochemical oxygen demand level in the water samples collected from the district within permissible limits. Neither was the ammonia content alarming.

But a senior official admitted that the sample was collected a considerable period of time after fish-kills were reported. “The findings can vary based on the timings of sample collection, he said.

The trade unions of NGIL have come out in support of the company stating that there was no basis to the allegation that the discharge of effluent was behind fish-kills in Chalakudy River. A release issued jointly by CITU, INTUC, and BMS said this was the first such allegation against the company in its 35 years of existence.

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