The Gharials (Gavialis gangeticus) is recently placed in 'critically endangered' category. In present scenario not more than 150 beeding Gharials are left in the wilderness. The reasons are fishing, netting, mining, agriculture on the banks of rivers, loss of breeding habitat etc. Recently 'toxin insult' in river Chambal has made the situation worse.
River Girwa in Katerniaghat Sanctuary is one of the 'last resorts' of Gharials in India. In recent past though the population has gone up, particularly the number of males have increased from 4-5 to 10-11. But the situation was not like this in the recent past. When I joined this place the natural breeding of Gharial was definitely in stress. The anthropogenic predation was the main threat. The Nepalese tribals used to steal the eggs to eat. The biotic pressure and grazing on sand bars of river Girwa was very high. The sand bar were frequently trampled by cattle of nearby villagers. The Gharials were not breeding properly that time and there was no observation or record to understand what is actually going on. In the year 2005 we started protecting nests of Gharial and we could locate only 4 nests of Gharials on a single sand bar. And that was the beginning of the work 'Operation Croc' in the river Girwa. Romulus Whitaker and B C Chaudhary were always helpful and gave valuable advise time to time. We started observing Gharials particularly their population dynamics.
In the year 2006, the number of nests reached to 18, which was undoubtedly very encouraging result. But at the same time we observed that the nesting has been done again on a single sand bar, which is relatively elevated in shape and has less threat from flood. That sand bar was badly eroded in the flood season. In the year 2007, before the 'trial nesting' started, we took the risk to manipulate the sand bar to 're-construct' to its original shape. We used the sand of Girwa to recreate the natural environ for the Gharials. It was a successful experiment. the Gharials accepted the sandbar for the nesting and laid eggs in 24 nest pits...The number had gone up. In the last July more than thousand hatchlings could come out from them. The mortality during hatching was not a problem, but the survival rate remain very poor due to fast flowing water during high flood season.
This year i.e. 2008 we again manipulated the same sand bar for the natural breeding of the Gharials. Which has shown positive result. Nearly 27 nests have been located so far. The sand bar is over crowded and high stratification and layering in the nesting process has been observed. Competition amongst the female gharials have been noted. Recently Romulus Whitaker was in K'ghat and after a long discussion with him we have decided to manipulate the near by sand bar in next breeding season. It will require removal of vegetation and creation of gentle slope so that Gharial may occupy 'that sandbar' for the nesting purpose. It is really encouraging to observe the result that number of nest has gone from '5 to 25' in last 3 years. We have collected data related to natural breeding of Gharials of K'ghat so that it can be used in documentation purposes. My team members particularly MK Shukla, Range Officer, Ram Rup and Somayi boatmen have really done a good job.
(Photo: A Gharial hatchling of last year)
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