Historically, gharial were common throughout the main rivers and tributaries of the Indus, Ganges, Brahmaputra, and Mahanadi-Brahmini systems, found in abundance from Pakistan in the west, through northern India and lowland Nepal, into Bangladesh, Bhutan and eastern India. It is possible they even occurred as far east as the Irrawaddy in Myanmar. The earliest known depictions of gharial are from 3000BC, with images of gharial found on seals and pottery from the Harappan Civilisation of the Indus Valley. Historical reports show that where gharial occurred they were very numerous, with descriptions of large groups of gharial basking on sand bars, one report from the late 1920s stated “45 gharial lying on the banks are extremely common in Oudh” (modern day UP), and they were known to “grow to great size” with reports suggesting gharial of over 25 ft long!

However, from the 1950s onwards gharial populations declined quickly, due to the construction of dams and barrages that altered their river habitats, as well as unregulated hunting, and mortality in fishing gear. By the 1970s, the gharial was facing extinction across its entire range, and successful conservation initiatives in Nepal and India in the 1980s and 90s slowed the gharial declines. Following these initial successes the gharial populations began to dwindle towards extinction once more, and the gharial was assessed at Critically Endangered in 2007, and remains so to this day.

Today, the gharial is found in just 14 fragmented localities in north India, lowland Nepal, and Bangladesh. Of these sites, only six are known to have had recent breeding, and only one – on the Chambal River in India – is a large and viable population. Conservative reconstructions of their historical extent of occurrence (based on evidence and reports) suggest that gharial today occur in less than 3% of their former distribution.

These fragmented populations continue to be threatened by existing and planned dams, barrages and other river modifications, continued mortality in fishing gear, as well as new problems including sand mining, water extraction, water pollution and introduced species. Each site where gharial occur has its own unique combination of threats, and there is a high risk that within the next decade gharial will no longer be found in many of these sites.

The current worldwide population is conservatively estimated to be 650 adult gharial, of which more than 77% are in the single population of the Chambal River.