Ecological and anthropogenic covariates ... - GANGAPEDIA

were on the same bank as the animals. Similarly, the presence of livestock in the
vicinity also appears to have a negative influence on use of a site. In addition, gharials
were unable to use mid river sand spits exposed in shallow areas because such
locations would be frequently used by people to cross the river. This implies that in
spite of additional available habitat for basking, gharials were unable to use them
because of humans using the same resource.
Sand mining along the banks of the Chambal appeared to have a severe negative
impact on gharial use of sites for basking. Continuous human activity in the mining
areas precluded the gharials from using these sites. Gharial numbers were consistently
lower in areas with mining operations, except one location where the height of the
sand bank excluded the mining from view of the animals. What is also significant is
the fact that mining usually takes place in large stretches of sand, areas that are
preferred by the gharial for basking and nesting. Sand mining therefore, not only
reduces the availability of sites for basking, but also poses a severe threat to the
reproductive success of gharials. In addition, sand mining also affects a suite of other
riverine species like turtles and ground nesting birds by excluding their use of sand
banks.
Land use changes along the river also appear to have a negative impact on habitat use
by gharials. Agriculture along the banks in all seasons, except when banks were
inundated due to flooding, was also viewed as a disturbance by the animals. I found
gharial numbers to be much lower in areas proximate to cultivations. Fishing
activities were another anthropogenic factor influencing the use of areas by gharials.
Again, gharial numbers were seen to be lower in areas where the intensity of fishing
activities was high. Gillnet fishing poses the danger of entanglement in the nets,
especially with smaller size-classes. Anecdotal reports mention that animals that are
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