Study of Vigilance Behaviour of Chital (Axis Axis)

Predation is an important agent of natural selection in animal communities and so vigilance behaviour has very high selection pressure acting upon it. During feeding bouts, though, herbivores tend to experience a trade-off between vigilance and foraging. Thus, vigilance as a behaviour pattern, ought to be tightly regulated by the cost-benefit ratios. A study on vigilance behaviour of chital (Axis axis) was conducted at Pench Tiger Reserve, Madhya Pradesh, India, from December 2008 to April 2009. The objectives were to examine the determinants of individual and group vigilance in chital; and also to examine the effect of conspecific behaviour on individual vigilance. What emerges is an interesting account of how vigilance behaviour is governed by group size, habitat visibility and the density of animals in the group. The results also allow a comparison of competing hypothesis to explain vigilance patterns and provide valuable insights into intra-specific variation.