Sunday, August 30, 2009

Gharial – The Last Swim


clip_image001[17]Known in India as the ‘Gharial,’ members of the genus Gavialis, are crocodile like reptiles with long narrow jaws. The Gharial derives its name from the bulbous pot (Ghara in Hindi) like growth on its snout which is used to produce sounds and bubbles associated with mating.
When it comes to size, the Gharial is the world record holder amongst all crocodilians, with adult males reaching a whopping 6-7 meters in length. None of the other crocodilians on the planet are a match for the Gharial’s ability at swimming and capturing fish. Broad webbed feet and a very well developed laterally compressed tail make it the fastest swimmer amongst all related contenders. The most striking feature of any Gharial is its highly specialized, tapering snout that possesses an array of interlocking needlelike teeth - 54 to 58 in the upper jaw and 50 to 52 in the lower jaw- that make it quite impossible for captured fish to escape. As the growing Gharial becomes a specialized fish capturing machine, its snout becomes progressively narrower.
Reproduction

Gharials mate during winters and the female lays 30 to 50 eggs in holes dug in the sand on the riverbanks from March to May. The sex of hatchlings is determined by the incubation temperature with males being born at higher temperature and females at lower temperatures.

Habit, Habitat and Ecological Importance

Gharials prefer calm waters of deep rivers. The last remaining Gharials on earth are confined to a few river systems of India. The Gharial may be specialized to eat fish, but amazingly the availability of fishes is higher in waters inhabited by the Gharial because Gharials feed on large predatory fishes that eat the commercially important ones.
Interestingly, Gharials have a taste for gold and diamonds! They swallow jewels, stones and other similar items that may have fallen into the waters and use them as ‘Gastroliths’ to aid in maintaining buoyancy and for digestion.
Population Status
At the beginning of this century Gharials were found in India, Pakistan, Nepal, Bhutan, Myanmar and Bangladesh. In 1940 their number was estimated to be between 5000-10000 but within 30 years, the Gharial reached the brink of extinction. Only 200 Gharials remained in India in1973.
India started a restocking program called ‘Project Crocodile’ in 1975 and Nepal followed suit in 1978. Breeding centers were established and 5000 young Gharials were released in protected areas. By 1996, it was believed that the crocodilian populations had stabilized and project crocodile was stopped. However, by 2004, only 200 breeding adults remained in the wild in India. In countries other than India and Nepal the Gharial’s fate has been even more tragic. It is probably extinct in Bangladesh, Bhutan and Myanmar and Pakistan.
Reasons for Decline

The story of the Gharial’s decline is one of ignorance, greed and apathy. Male Gharials are hunted mercilessly for the aphrodisiac properties associated with the pot in its snout. Excessive fishing has reduced fish populations on which the Gharials thrived and human encroachment has destroyed most river banks where Gharials nested. Gharials caught accidentally in fishing nets are either hacked to death or have their snout chopped off by fishermen to save the net. Certain tribes consume Gharial eggs and their dietary habits have contributed to the dwindling numbers of Gharials.
In the Chambal sanctuary, the largest habitat of the Gharial in the world, large scale illegal mining by the sand mafia has made the banks too steep for the Gharial to climb on or to lay eggs. Water pollution is also taking its toll on the Gharial. In December 2007 alone, more than 50 Gharials in the Chambal sanctuary died due to unknown reasons. It was suspected that they had died after eating fish contaminated by industrial pollutants.
Steps for Protection

The ‘Gharial Conservation Alliance’ created in 2004 is working for the revival of the Gharial population. The last remaining Gharials are protected in the National Chambal River Sanctuary, Son Gharial Sanctuary, Ken Gharial Sanctuary, Sathkosia Gorge Sanctuary and Corbett National Park in India and the Royal Chitawan National Park in Nepal.