Abstract

Studies on the impact of the Idukki hydro-electric project on the larger mammals were carried out for a period of about four years from 1981 to 1984. The study area is located in the Idukki district of Kerala. Forest types consist of grasslands, deciduous and evergreen forests. Study methods included collection of details of animals from systematically laid out sample plots, examination of population parameters from sighting data and recording of habitat quality on gridded map. About 75 elephants are estimated to be present in the area. The herds were of a smaller size indicating disturbance. The proportion of various classes of individuals and their sex ratio was not similar to that in other populations. There were only very few young ones. Numberof male elephants in the population was also very low. Animals like sambar, barking deer, jackal and wild dog were present in the study area. But their number was very low. The study area contained wild boar and hare in moderately good numbers. Gaur, bear, tiger and leopard are no more found in the area. The bonnet macaques in the periphery of the reserve indulged in a great deal of crop raiding. Wild dogs attacked domestic cattle in a few cases. The study shows that construction of the Idukki hydro-electric project had an adverse effect on many animals. In addition to the construction of dams, large scale encroachment and forest colonisation also played an important role in the destruction of animals. As far as animals are considered there were both negetive and positive impacts. The study recommends habitat improvement measures for the Idukki wildlife sanctuary need for keeping the forest continuity of crucial Meenmutty region, and a few other measures to prevent further deterioration of the habita