In the winter of 2002/3, I found myself in Kabini managing a ‘farmhouse’ that was taking its first baby steps towards becoming a ‘wildlife resort’ and if you had asked me a year earlier if that was where I saw myself a year hence, I would have laughed in your face. As the 1900s turned to the 2000s I was happily living on the Bhutan border, indulging in my love for photography and wildlife.
I did not know it then but the then dreaded but now forgotten Y2K problem culminated in me reaching Kabini in the middle of the night to discover that my quarters had an outdoor toilet without a door. Not wanting to make a fuss, I decided to tackle the problem in the morning by catching the first available transport out. As the day broke and I got my first look … the rest is, as they say, history.
I eagerly embarked on the next phase of my wildlife journey, exploring the forests of Kabini and honing my skills. Up until then, I was happily engrossed in tackling the human-elephant conflict prevailing in the Dooars and keeping track of the resident leopards on the estate. I enjoyed my wildlife in the Dooars, studying elephant and, to a lesser degree, leopard behaviour.
It was not long before I realized that there was something unique about the place that did not quite gel with what I had experienced before. In Kabini I regularly found tigers, leopards and wild dogs in the same areas, sharing space and seemingly coexisting pretty well. Conventional wisdom told me that this was not how it was meant to be. I mentioned this to some people but did not get a satisfactory explanation — for them, it was what they were used to.
Not satisfied, I decided to put it aside for the moment and got back to the daily grind. I was fortunate that the owner and my boss was himself very keen on wildlife was also very active in the conservation movement in the state. Because of this, I got to interact with eminent researchers and scholars from India and around the world. One such person was Dr K Ullas Karanth and I was able, with the help of his assistants, to get hold of some of his studies conducted in the Park — you have to remember that those days there was no mobile connectivity leave alone internet in Kabini and getting hold of any scientific information was very difficult. As expected, within those papers I found the answers I was looking for. I will now attempt to cut through the jargon and explain the same to you. Rest assured that what I am about to outline below is based on proper peer-reviewed scientific research and any errors are solely due to my misunderstanding them.
The Nagarhole National Park, of which Kabini is a part, has a large number of predators and the three major predators of the park are the tiger, wild dog and leopard. As mentioned earlier these three major predators co-exist here in high densities due to a unique set of factors or circumstances.
To fully understand the relationship and dynamics between predators we first need to look at their basic requirement — food or the herbivore density and the availability of prey species in the area. Without prey, it is impossible to have any predators and hence both the number and type of herbivores present play an important role. It is not just a question of numbers it also boils down to the kind of prey, for example, a forest inhabited only by hares cannot expect to hold tigers as hares make too small a meal for tigers regardless of the number of hare in that forest.
Nagarhole has a large number and variety of large herbivores (defined as weighing more than five kilos) and these include seven species of ungulates and two species of primates. Among these herbivores, the Chital, Sambar, Gaur, Wild Pig, Muntjak and the langur constitute almost the entire diet of the three. It is also interesting to note that all three, more or less, hunt the same species.
However, when we further sub-divide them by body weight into large, medium and small, we find that the three predators have very distinct preferences. The average weight of prey killed by each worked out to 92 kgs, 38 kgs and 43 kgs, clearly showing the niche occupied by each predator.
The study also showed that there was species selectivity among the predators with gaur being preferred by tigers and wild pig being avoided by leopards and langurs being underrepresented among the wild dogs. Further tiger perdition also showed a bias towards adult male chital, sambar and wild pig. Wild dogs were found to prey selectively on adult male chital while leopards avoided them. The studies showed that as there is a choice in Nagarhole, because of the availability of prey in the appropriate size class, the larger predators selectively kill larger prey which in turn facilitates co-existence.
Behavioural and hunting techniques and patterns also play an important role in the relationship between these three predators. The study showed that wild dogs hunted almost always during the day probably because of their hunting method — they course or run down their prey and therefore find it easier to hunt during the day when visibility is good. Another reason is that they prey mainly on chital who are more active during the day.
Tigers and leopards were found to be more nocturnal hunters thus there was some temporal (time) separation between them and the dogs. Leopards were also found to be more active during the day in comparison to tigers. This can be explained by the fact that leopards kill a relatively larger proportion of prey that are active during the day like the langur and chital. Even at night leopards were found to be more active than tigers. This was because they spend more time searching for prey due to the higher proportion of smaller nocturnal animals in their diet. However, their activity pattern does not show any active avoidance of tigers by hunting at different times of the day.
The studies also showed that there is no separation based on hunting areas selected by the three. All three attacked their prey close to habitat features where prey concentrated to feed or drink. However, tigers killed their prey where the cover was significantly denser in comparison to leopards, most gaur (potentially dangerous) were attacked in more open areas where visibility was higher. Leopards killed chital in more open areas than tiger as they have a greater ability for concealment in sparse cover.
Both leopards and tiger were found to drag their kills into cover, the dogs, however, did not drag their kills and any drag seemed incidental to the feeding process.
Tigers dragged their kills into dense to moderate cover but left some of their kills in the open, these being all gaur too heavy to carry. The leopard on the other hand dragged very few of their kills up into trees and also left a significant number in the open. Most wild dog kills were left in the open.
Field observations showed that leopards flee tigers and wild dogs by climbing trees. Tigers also appropriated wild dog and leopard kills. Wild dogs were observed scavenging tiger and leopard kills when they were away. In one instance the leopard returned to the kill later. On one occasion a tiger and leopard fed on kills less than 300 meters apart without being aware of each other. On another occasion, a pack of wild dogs were 50 meters away from a resting tiger again without either being aware of each other’s presence. This showed that both tigers and wild dogs are socially dominant over leopards but all three share the same space. However, tiger and leopards kill and eat wild dogs occasionally. The impression is that the need to defend kills does not play a significant role because of the dense cover and high tree density in Nagarhole.
It can be summarized that ecological factors such as availability of appropriate size prey, dense cover and high tree density are the reasons for the coexistence of these three in high densities in Nagarhole. Behavioural factors such as habitat preference, choice of hunting sites or social dominance, are of lesser importance in Nagarhole when it comes to predator densities.
Well, I hope this made sense to you but it was eye-opening for me. A lot of water has flowed under the bridge since these studies were conducted and I left Kabini. The predators have become used to the safari jeeps and, especially Tigers, are seen more often. I am sure that tigers being less circumspect than before has, in turn, affected both leopard and wild dog behaviour. From what I see on social media, and there is a lot on social media, leopards are now mostly seen on trees — which, with tiger moving around with confidence, is not surprising. This was hardly the case during the decade or so I spent there, I saw most of my leopards walking on the ground. Well as they say change is the only constant and I guess it’s time for another study — any takers?