Friday, March 13, 2009

Radio tagging to track Nepal's endangered gharials






One of the world's largest crocodilian species is also its rarest. With just a few hundred individuals left, the critically endangered gharial (Gavialis gangeticus) faces an uncertain future in its remaining river habitats in India and Nepal. Once common, gharials were hunted into near extinction for their skins inthe early 20th century. Since then, captive-bred gharials have been released into rivers by the hundreds, but survival rates have been low, probably because so little was known about the species. Last year, more than 100 gharials mysteriously died in India. While the cause of death has never been conclusively proven, scientists at the time hypothesized that they died of gout (a build up of uric acid, a waste product), brought on by kidney failure, which itself was brought on by exposure to toxic chemicals in India's polluted rivers. Now, scientists in Nepal are trying to find out as much information as possible about their country's gharials so they can devise a plan to keep this increasingly rare species from disappearing forever. The project started a few weeks ago, when Nepal's Department of National Parks and Wildlife Conservation, in collaboration with WWF Nepal, attached RFID tags to 14 gharials and re-released them in the Rapti River. The project, set to run through December, will gather information about gharial habitats and behavior, says Rinjan Shrestha, a WWF Nepal conservation biologist. Shrestha says that "habitat degradation, overfishing and water pollution"are the main reasons for gharial decline in Nepal."The radio tags are used to locate the position of the released gharials,"says Shrestha. Once located, the monitoring crew will record the gharials'GPS positions. "We have to localize every tag manually, with a directional antenna," says Antoine Cadi, a project manager at Awely, an environmental NGO in France, who is providing technical assistance for the program. "This method is less expensive than satellite tracking and gives us the opportunity to follow the behavior of the crocs."The team will try to locate the gharials daily until July, when monsoon season begins, "then do our best during the raining period," Cadi says, noting that researchers will step up efforts again in September to gauge the impact of monsoon flooding on the shrinking population. Cadi believes that monsoon season may drive gharials from Nepal's into India, where they could face greater threats. "Every day theyare pushed down the river... and, after some months, they can not avoid crossing the dam," he says, "and finally arriving in India, where all thethreats known in Nepal are more important and strong."
Note: This news story was written by John Platt Mar 12, 2009 regarding new development related to gharial conservation, which was posted by Janki Lenin on GCA/GMTF mailing list.
The similar efforts are being taken in the recent past in Chambal (India) by WWF-India under 'River Watch' programme, in which Drub Basu is monitoring the gharials movement and all. Recently gharials were released in upper ganga near Narora with the active involvement of Bivash Ranjan, Conservator of Forests, Meerut and Parikshit Gautam (WWF). And the credit goes to Rom Whittaker that 'Crocodile blues' which was aired recently on 'Animal Planet' drew the attention of many of us regarding the extinction of gharials from their centuries old natural habitats. Another research is being done by Laurel and Abhijit (under the supervision of Rom) regarding the behaviour of Gharials at Katerniaghat. This is true we still do not know many thinks related to the behaviou of the gharial and their population dynamics.
But all these measures are insufficient to save just 200 left breeding gharial population in the country. The problems like mining, indiscriminate fishing, poaching, water pollution and loss of breeding grounds in their natural habitat are of very serious nature, which does not need research right now, rather they need concrete steps to save this diminishing species from the nature. This is not the time to know how gharial behaves with muggar or where do they go when the flooded rivers carry away everything with them. This is the time to give them protection at fullest extent, un-polluted water in the rivers and mining and predation free sandy banks to lay the eggs. The next breeding season will strart from April, which is just ahead and we dont know what will be the result this year. Lets hope good for gharial.
-Ramesh Pandey, New Delhi

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