An Ecological Study in the Buffer Zone of the Corbett Tiger Reserve: Tiger Abundance and Cattle Depredation

摘要

We studied the problem of livestock depredation by tigers in and around buffer zone of the Corbett Tiger Reserve. Data were collected on all cases of livestock kills by large carnivores in and around buffer zone from October 2002 to September 2003. Secondary data on livestock kills and abundance of tigers were collected from the forest Department. Data were analyzed by standard statistical procedures and using GIS software Arc GIS (8.3). Block wise calculation of tiger abundance based on censuses conducted in 1999, 2001 and 2003 showed that the blocks in south and south east zone of buffer zone had highest concentration of tigers accounting for 36.5%, 43.5% and 44.7% of tiger population. The tiger abundance was positively correlated with ungulate densities. A total of 311 cases of livestock kills and injuries were recorded. A total of 61% livestock kills and 18.6% injuries were by tigers alone in and around buffer zone. The magnitude of livestock kills and injuries showed close resemblance with past pattern documented in 2001 and 2002. While 30.5% of livestock kills were recorded inside the buffer zone boundary, 69.5% livestock Rills were recorded from outside the buffer zone. Most of the livestock kills were documented on south and southeast portion of buffers zone where maximum concentration of tigers was recorded in last three censuses. The number of livestock kills showed substantial increase in rainy season as compared to winter and summer. Tigers killed significantly higher number of cows than buffalo in buffer zone. The distribution of livestock kills showed significant differences in terms of sex of prey species, weight categories, vegetation types, topography, tree and shrub cover, distance to water and human settlements. The analysis of 38 tiger scats collected from inside the buffer zone showed that chital and sambar contributed 47.9% and 14.6%, respectively to the tiger diet in buffer zone. The observed dietary pattern based on scat analysis showed a very low contribution of livestock species to the tiger diet which is in contrast with the high level of livestock depredation by the tigers in and around buffer zone of CTR.