Some more details of yesterdays fantastic tiger sighting.

The mahouts had located a male tiger following his pug marks and the alarm calls of chital. This is the usual method of finding tigers. There is a forest early warning system and with practice it is possible to identify the specific warning calls of both Chital and Langur. The two live in a relationship that is sometimes described symbiotic as both provide effective alarm calls in the presence of two highly effective ambush predators (tiger and leopard here in Kanha, other species elsewhere). Is it actually symbiotic though ?  In addition the langur has untidy eating habits and as they feed in the canopy they drop a lot of potential foodstuffs that are otherwise unavailable to the deer. I’ve seen a paper that suggests that langur will drop around 4kg of foodstuffs daily that it is regularly foraged by chital. Associations are more common during the non-monsoon seasons (either hot or cold). Chital are much more vulnerable to predator attack than Langur as they are vulnerable to tiger, leopard and dhole (the three major predators here at Kanha), whereas Langur tend to retreat to the safety of the canopy, and are rarely predated by tiger (presumably because of size and their arboreal nature. It is clearly advantageous to Chital to associate with Langur, both for dietary reasons and for security but what is in it for the Langur ?