Analysis of a Nilgiri langur (Presbytis johnii) home range change

Little published information exists detailing home range changes among nonhuman primates. Resulting from human destruction of the habitat, one of the observed Nilgiri langur troops was forced to relocate its home range, during which several interesting behavioral patterns emerged. Most important was the observation that the animals were very reluctant to desert the home range, even when the last trees in the core area were being destroyed. Adult males and adult females responded differently to the destruction and resultant shift. The males appeared less nervous than the females and deserted the home range prior to them. The reaction of surrounding troops to the shift of troop A, strongly suggests territorial behavior among Nilgiri langurs. Finally, this shift, along with other observations reported elsewhere, demonstrates that Nilgiri langurs are quite adaptable and appear to possess the ability to survive in an ecology being rapidly destroyed by the human population.This study was supported by Public Health Service grant MH 11099-01 attached to Fellowship 2 F1-MH-22, 140-02 (BEH).