Conservator of Forests Eva Sharma says ghariyals below the age of three years would be released.

Defending the decision, she says: “The NCS informed us that only those ghariyals already in the Chambal river had died. None of the ghariyals sent from the Kukrail Ghariyal Rehabilitation Centre (KGRC) were found dead.”

The KGRC has been releasing ghariyals into the Chambal river since 1970. It chops the tail of the animal to ensure that it can be spotted easily.

Conservationists believe there are only about 1,500 ghariyals left in the wild, many of them in the Chambal, one of the few unpolluted rivers in India. The Chambal contains the largest of three breeding populations in the world.

The ghariyal was on the verge of extinction in the 1970s, when a government breeding programme that has released several hundred into the wild raised their numbers.