Kathmandu, July 3:

The number of gharials, the slender-nosed crocodiles, found only in South Asian rivers, is drastically decreasing due to increasing human activities and pollution in their habitats.

The gharials are also hunted for their skin because the locals believe in mystical power of the snouts of male gharials.

Nepal had 222 gharials in six river systems — Narayani, Rapti, Kali Gandaki, Sapta Koshi, Karnali and Babai — until 1985 but the number has reduced to 81 and the species is no more found in the Koshi river system.

According to a recent study done by the Department of National Parks and Wildlife Conservation (DNPWC) with the help of WWF-Nepal, there were 41 gharials in Narayani river, 24 in Rapti, 10 in Babai and six in Karnali.

Although Nepal released over 661 gharials in different rivers from the breeding centres in Chitwan and Bardiya, 580 of them failed to cross the age of 30 even though gharials have a life span of 100 years. Gharial is listed as endangered and on Appendix I of the CITES.

Narendra Pradhan, an ecologist at the DNPWC, said habitat loss along with intensive fishing and river pollution was the leading cause for declining crocodile population.

A breeding centre in Chitwan often releases gharials in the nearby Narayani river but the environment along the river banks is so polluted that a gharial was found running way from the river bank.

“We were surprised to see that a gharial was walking its way back to the breeding centre days after it was left in the river,” he added. Dams constructed across the river on the Indian side had also restricted free movement of gharials, causing damage to their natural growth, he said.

Former acting director general of DNPWC Shyam Bajimaya said that unscientific fishing techniques were also the reasons behind the decreasing number of gharials.