The not-so-humble Sri Lankan leopard (Panthera pardus kotiya) is one of Sri Lanka’s most charismatic creatures and can be found in many parts of our tropical island paradise.
When it comes to conservation, leopards get quite a great deal of attention. This is partly because they’re charismatic (and, by many definitions, cute) and also because they are a keystone species – their ecological value is quite high and because of their nature and their place within an ecosystem, protecting them protects a host of different species within their ecosystems, allowing for more thriving biodiversity overall.
A recent survey done by a group of wildlife researchers has shed new light on leopard behaviour within Wilpattu National Park, Sri Lanka’s largest protected area. Taking place over the span of three months (a single season), the survey used camera traps to document the behaviour and incidences of leopards within Wilpattu National Park (save one block of the park) to collect data like density, abundance, sex-specific movement, and spatial distribution in order to gain a clearer picture of leopard activity and work towards better conservation of this captivating species.
The Sunday Morning Brunch chatted with one of the lead researchers behind the survey, conservation scientist and herpetologist and Wildlife Research and Nature Conservation Foundation Founder Dinal Samarasinghe, who took us through the survey, its findings, and its implications for conserving leopards going forward.
The survey itself
Dinal, whose current research focus is on human-animal conflict mitigation and monitoring carnivore/apex predator population, and who is also Research Investigations Officer at the Environmental Foundation Limited, spent three months based in Wilpattu along with other members of the research team.
“We wanted to look at the population density of leopards within a large protected landscape and look at leopards’ specific movements, detection rates, sex ratios, and other important parameters to determine population health,” Dinal said, speaking of the foundation of the survey, explaining that this survey functions as a sort of mapping exercise that sets a baseline for leopard activity and populations, and that the team hopes to do both a second survey within Wilpattu National Park itself as well as another corresponding survey within Yala National Park to collect more data that can be used to gain a better understanding of the leopards.
“Looking at animal numbers over time helps a lot with management and conservation of that animal and one of the reasons we wanted to do the survey is that some of my colleagues have been going to the park for over 30 years and from experience we know that there are a lot of leopards,” Dinal shared, “but what we don’t know is their population density, and how that compares with other protected landscapes like Yala and Horton Plains.”
The survey also tackles leopard population within a challenging landscape – Wilpattu National Park is Sri Lanka’s largest protected area and in terms of the landscape itself can be very tough terrain. It is also adjacent to several other protected areas with varying degrees of protection.
The survey used camera traps to document leopard activity. Camera traps are cameras equipped with motion sensors that are automatically triggered by a change in some activity in its vicinity, like the presence of an animal, and are frequently used in surveys to document animal presence and activity.
The survey was conducted during the dry season in two plots over two consecutive sessions with camera traps set up along game trails, dry stream beds, and motorable park roads as leopards are known to regularly travel, hunt, and scent mark along them. All evidence of potential leopard presence was also documented during the survey, including droppings, scrapes, and tracks during foot surveys.
The key findings of the survey
The results of the survey indicated that Wilpattu National Park supports a density of 18 individuals/100 km². In terms of individual leopards, the survey recorded a total of 133 leopards (116 adults and 17 cubs). The estimated range for adult leopards (over two years old) was found to be 49.53 km² for males and 22.04 km² for females. The survey also showed a healthy sex ratio with female:male ratio of 2.03:1.
On a practical level, Dinal explained that the survey shows that Wilpattu National Park has a healthy leopard population with many female leopards present as well as a population that is spread out quite well spatially. One thing that Dinal feels contributes to Wilpattu’s leopard population being so well spread out is the fact that the Wilpattu National Park has other protected areas in its periphery, which gives leopards, especially young males, more area to disperse, though this is something he highlighted would need further research to determine.
The extensive camera trapping has also shown some interesting phenotypes among the Wilpattu leopards, some of which will require further study; for example, Dinal shared that there were leopards who had kinked tails (tails bent at the base and at the end), something that is usually a sign of inbreeding, and animals like the Florida panther who showed this phenotype were genetically proven to be inbred. This possibility will be the subject of further research.
Over the course of the survey, Dinal and the other researchers within the team also saw a lot of human activity taking place within the park, some of which, like poaching, is illegal. Such behaviour when observed had been immediately reported and had been usually observed near the entrances to the park and in areas with little to no tourism activity.
How the survey can help with leopard conservation
The biggest implication of the survey is that it proves that there are high densities of leopards in Sri Lanka even in parks outside Yala which is traditionally known for being the most leopard-dense location. Commenting on the robusticity of leopards, Dinal also said this highlighted the need for conservation, for these populations to grow. The Sri Lankan leopard is an endangered, endemic subspecies, and the fact that we are seeing high densities in leopards now is by no means reason for conservation to take a back seat.
Habitat losses, hunting for trade, and fragmentation have become reasons for the Sri Lankan leopard to rapidly decline in numbers, and now that we are seeing growing densities in leopards, we need to continue conserving this species, both for its ecological value within our biodiversity systems and for its value as a natural resource for tourism.
Knowing that we have high densities of leopards in Wilpattu National Park means that conservation measures can be effectively taken to help this population continue to grow. For example, Dinal pointed out that leopards need to be able to move between large plots of land, and so, the Government should consider reversing things like the cancellation of the 5/2001 circular which removed protection from many areas of land and reinstate such protections.
Minimising the human-animal conflict is also an important step to take. “I think when it comes down to it, it all depends on mindset. It’s important that people, in general, become aware of the wildlife they are living with, and that applies to everyone in Sri Lanka. We do have different perspectives and different life experiences with animals based on where we are living,” Dinal explained.
“Someone living close to a wildlife park or reserve, especially, must have an understanding of the wildlife they are living with, and even if they don’t live near a reserve, it’s important to remember that Sri Lanka is a very important island in terms of biodiversity, and just like you have to be up to date with the economical situation of the country and developments in the health sector or other sectors, as a member of the general public living in an island with such rich biodiversity and endemic species, it’s important to be equally knowledgeable on our natural resources and the need to conserve them.”
Considering the uncertain economic state of the country and the crises we are currently navigating, Dinal also shared that it was very likely that we would see more encroachment into national parks and protected areas in the future – both in terms of poaching for income as well as people encroaching on the parks to facilitate subsistence; other than the fact of breaking the law, this will also result in an increase in potentially unsafe encounters with wildlife for all parties involved.
The lighter side of the survey and what comes next
Sharing some of his most memorable non-research related moments of conducting the survey, Dinal explained that there were many memorable moments captured by the camera traps of animals interacting with the cameras and just living their lives in general, but one that stood out to him was an encounter captured on camera of a mother leopard and her cub on the main road to Mannar, which runs through the park, with the cub being very interested in the camera trap. This moment also highlighted the need to notify park officials that the main road is a high-risk area for human-animal conflict because leopards tend to travel along the road, especially at night (leopards are largely nocturnal) and the road is also well-used by people.
Encounters with curious animals, while memorable, had also posed their own challenge. As Dinal shared with us, other animals like bears and elephants would try to take camera traps down, making it quite a struggle to keep, maintain, and collect data from the traps. “We eventually did manage to outsmart the bears, but it was more difficult with the elephants,” he recalled.
For its next step, the team wants to continue surveying Wilpattu National Park, including the areas they weren’t able to map effectively, and also do a similar survey of Yala National Park so they can paint as clear a picture as possible of the Sri Lankan leopard. With the Yala survey especially, Dinal shared that they hoped to adopt a more multistakeholder approach and engage with different industries like tourism to help them collect better and more accurate data.
“My favourite part of the whole process was the whole science behind it,” Dinal shared, commenting on what drives him as a researcher, “asking the right questions, collecting the data to question your hypothesis, and then coming to a conclusion. For me, the whole process is very satisfying.”