The Life of Animals | Gharial | The Gharial (Gavialis gangeticus), also called Indian gavial or gavial, is the only surviving member of the once well-represented family Gavialidae, a long-established group of crocodilians with long, slender snouts The gharial is listed as a critically endangered species by IUCN The gharial is one of the three crocodilians found in India, the others being the Mugger crocodile and the Saltwater crocodile It is one of the longest of all living crocodilians.
Gharials are exceeded in size only by the Saltwater Crocodile. land, however, an adult gharial can only push itself forward and slide on its belly. Its elongated, narrow snout becomes proportionally shorter and thicker as an animal ages. The bulbous growth on the tip of a male’s snout renders gharials the only visibly sexually dimorphic crocodilian. This growth is present in mature individuals and called ghara after the Indian word meaning “pot”. The average size of mature gharials is 3.6 to 4.5 m (12 to 15 ft) The three largest examples reported were a 6.5 m (21 ft) gharial killed in the Gogra River of Faizabad in August 1920; a 6.3 m (21 ft) individual shot in the Cheko River of Jalpaiguri in 1934; and a giant taped at 7 m (23 ft), which was shot in the Kosi River of northern Bihar in January 1924
The jaws are lined with many interlocking, razor-sharp teeth — 27 to 29 upper and 25 or 26 lower teeth on each side. The front teeth are the largest. The gharial's snout is narrow and long, with a dilation at the end and its nasal bones are comparatively short and are widely separated from the pre-maxillaries. The nasal opening of a gharial is smaller than the supra-temporal fossae. The gharial's lower anterior margin of orbit (jugal) is raised and its mandibular symphysis is extremely long, extending to the 23rd or 24th tooth. The length of the snout is 3.5 (in adults) to 5.5 times (in young) the breadth of the snout's base. Nuchal and dorsal scutes form a single continuous shield composed of 21 or 22 transverse series. Gharials have an outer row of soft, smooth, or feebly keeled scutes in addition to the bony dorsal scutes. The outer toes of a gharial are two-thirds webbed, while the middle toe is only one-third webbed. Gharials have a strong crest on the outer edge of the forearm, leg, and foot. Typically, adult gharials consist of a dark olive color tone while young ones are pale olive, with dark brown spots or cross-bands.
Gharials thrive in deep rivers. In India, small populations are present and increasing in the rivers of the National Chambal Sanctuary, Katarniaghat Wildlife Sanctuary, Son River Sanctuary and the rainforest biome of Mahanadi in Satkosia Gorge Sanctuary, Orissa, where they apparently do not breedIn Nepal, small populations are present and slowly recovering in tributaries of the Ganges, such as the Narayani-Rapti river system in Chitwan National Park and the Karnali-Babai river system in Bardia National Park. They are extinct in Pakistan's Indus River, in the Brahmaputra of Bhutan and Bangladesh and in the Irrawaddy River in Myanmar. There have been some small-scale projects to breed and rehabilitate gharials, like in Nepal's Chitwan National Park. Young gharials eat insects, larvae, and small frogs. Mature adults feed almost solely on fish, although some individuals have been known to scavenge dead animals. Their snout morphology is ideally suited for preying on fish. Their long, narrow snouts offer very little resistance to water in swiping motions to snap up fish in the water. Their numerous needle-like teeth are ideal for holding on to struggling, slippery fish. Gharials will often use their body to corral fish against the bank where they can be more easily snapped up
The mating season is during November through December and well into January. The gharial is not a man-eater and is sensitive towards humans. The drastic decline in the gharial population can be attributed to a variety of causes including over-hunting for skins and trophies, egg collection for consumption, killing for indigenous medicine, and killing by fishermen. the excessive, irreversible loss of riverine habitat caused by the construction of dams, barrages, irrigation canals, siltation, changes in river course, artificial embankments, sand-mining, riparian agriculture, and domestic and feral livestock, which have combined to cause an extreme limitation to gharial range. Since 2007, the species is listed as Critically Endangered on the Red List of Threatened Species issued by IUCN, and protected by CITES Appendix I. Conservation programs have been undertaken in India and Nepal, based on the establishment of protected areas and restocking these with animals born in captivity, but nowhere has restocking re-established viable populations Since 1981, more than 3000 young gharial have been released into the wild. The release of captive gharials was not as successful as expected. Recently, more than 100 gharials died in India in the Chambal River from an unknown cause with gout-like symptoms.
On December 27, 2010, the then Indian Minister for Environment and Forests, Jairam Ramesh, during a visit with Romulus Whitaker at the Madras Crocodile Bank, announced the formation of a National Tri-State Chambal Sanctuary Management and Coordination Committee for gharial conservation on 1,600 km2 (620 sq mi) of the National Chambal Sanctuary along the Chambal River in Madhya Pradesh, Rajasthan and Uttar Pradesh. The Committee will comprise representatives of three states' Water Resources Ministries, states' Departments of Irrigation and Power, Wildlife Institute of India, Madras Crocodile Bank Trust, the Gharial Conservation Alliance, Development Alternatives, Ashoka Trust for Research in Ecology and the Environment, Worldwide Fund for Nature and the Divisional Forest officers of the three states. The Committee will plan strategies for protection of gharials and their habitat. Although gharials have sacrificed the great mechanical strength of the robust skull and jaw that most crocodiles and alligators have, and in consequence cannot prey on large creatures, the educed weight and water resistance of their lighter skull and very narrow jaw gives gharials the ability to catch rapidly moving fish, using a side-to-side snapping motion.
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