Rise in Mugger numbers likely to pose risk in Chambal Sanctuary

In the wild, it is Darwin theory of evolution- the survival of the fittest that determines the natural selection and is significantly demonstrated in the population increase of more aggressive fresh water crocodilian species at National Chambal Sanctuary in Morena district of Madhya Pradesh. Over the years proportionate rise in mugger population in upper reaches of the sanctuary as compared to Gharial is likely to pose a serious risk if phenomenon goes unchecked. Though duo of mugger and gharial share same habitat, the mugger is more adaptive and can survive in marshy wetland and upper reaches. While the Gharial settles in untamed wilderness of downstream deep pools and expanses of undisturbed sand/ mid-river islands. It,fresh water gharial, is listed as critically endangered with IUCN's (international union for conservation of nature) Red List of threatened species. They have distinct boss at the end of snout, which resembles an earthenware pot known as Ghara, hence the name Gharial. The gharial is well adaptive to catching fish because of its long, thin snout and sharp interlocking teeth. According to estimates the oldest known depictions of gharial are about 4000 years old and found in Indus Valley. The Hindu regarded it as vehicle of river deity Ganga.

The rise in Mugger population in National Chambal sanctuary,from 464 in 2016 to 710, is set to translate into shrinking habitat for Gharial and thus decline in latter’s population. Ironically Gharial sanctuary with its rehabilitation/reintroduction/conservation/protection programme together with breeding centre at Deori (Morena district) has been able to record marginal increase. The latest survey (Feb 2020) has pegged the gharial population to 1859 from 1162 recorded in 2016. Experts attribute the anomaly to several factors including aggressive behavior and eating habits that mugger sometimes eat their own calves besides also feed on gharial hatchling and calves. Conservationist and forest official (retd) Dr RK Sharma said the sanctuary is being used as dumping ground. A large number of rescued muggers from other places are released here in Chambal River. He expressed concern by adding that if trend continues the mugger population will outnumber critically endangered gharial. It has reportedly been witnessed in one of the gharial sanctuary located in Orissa, maintained Sharma.

If the mugger were the main threat in upper reaches of the river, downstream, it was fishing. An increasing number of gharials were being caught in fishing nets. Another problem was the illegal mining on the river bank, which had destroyed the steep banks used by gharial for nesting and laying their eggs. The wide disparity in adult sex ratio (male and female gharial) also attributing to the decline in gharial population.

Source: DFO (Morena).