Mass mortality of migratory birds at Sambhar lake not due to 'avian influenza', NGT told

The National Green Tribunal was told by a committee on Friday that mass mortality of migratory birds at the Sambhar Lake in Rajasthan was not because of 'avian influenza' or 'pesticide poisoning' but due to avian botulism caused by a bacteria.

Avian botulism is a serious neuromuscular illness of birds caused by a toxin that is produced by the bacterium clostridium botulinum. Avian botulism has been recognised as a major cause of mortality in wild birds.

A report filed by member secretary of the Rajasthan State Wetland Authority told a bench headed by NGT chairperson Justice Adarsh Kumar Goel that the matter is also being looked into by the high court and action of collection of carcass from the site and their disposal in the pits.

"The report mentions action of collection of carcass from the site and their disposal in the pits. The report also mentions rescue and rehabilitation of certain birds at emergency rescue facility and shifting to soft release enclosure. Mass mortality was not due to 'avian influenza' or 'pesticide poisoning' but due to avian botulism caused by Clostridium botulinum," the tribunal noted.

The NGT after perusing the report said that it does not give any reason for spread of avian botulism and this could happen as a consequence of illegal extraction of water for salt production, water pollution or on account of excessive agriculture practised in the catchment area of the lake, decrease in the extent of the water body from 74.63 per cent to 35.1 per cent or such other reason.

"In such a case, it may be necessary to take action accordingly, apart from taking requisite steps to check seepage of toxins, demarcate the buffer zone as per the Integrated Wetland Management Plan and to recover environmental compensation. Let these aspects be gone into and a further report furnished.

"Having regard to sensitivity of the matter, it will be appropriate to have personal interaction with the key authorities dealing with the matter. Accordingly, the member secretaries, National Wetland Authority, government of India, State Wetland Authority, Rajasthan, Rajasthan State PCB and the District Magistrate, Jaipur may remain present in person on the next date," the tribunal said.

The bench posted the matter for next hearing on March 17.

The green panel had earlier sought a report after taking note of a news item which said that carcasses of about 18,000 migratory birds have been found at the Sambhar lake in Rajasthan.

The NGT passed the order after taking note of a news report in Hindustan Times under the heading "Sambhar's ecology among worst, alarm carcasses of about 18,000 migratory birds have been found near the Rajasthan lake, triggering concerns amount environmentalists".

According to the report, carcasses of 18,000 migrated birds were found at the Sambhar lake 80 km South West of Jaipur on November 10.

"Apprehension is that deaths of such large number of birds have taken place on account of violation of environmental norms in maintaining the ecosystem of the wetland in question, including water quality, plant invasion in water bodies," the report said.

Carcasses of hundreds of birds, including plovers, common coot, black winged stilt, northern shovelers, ruddy shelduck, and pied avocet were found scattered on the edge of 12-13 km of the catchment area of the lake, bird experts had said.