Camera trapping the elusive leopards of Wasgamuwa
Caught on camera: Leopards emerge as night falls on Wasgamuwa Park
As dusk descended gradually obliterating the land of its features we slowly headed towards the entrance to the Wasgamuwa National Park, cruising on the dusty dirt track that wound alongside the dried grass plains. And then suddenly there by the forest edge was a solitary leopard! It was sitting on its haunches with the head and shoulders showing above and blending beautifully with the rustling grass tinted a golden hue by the sinking sun. From its alert posture we deduced it was on the hunt. Slowly drawing to halt we experienced probably one of the rarest encounters in Wasgamuwa͟—meeting a ghost of the forest, the Sri Lankan leopard (Panthera pardus kotiya).
One of the most striking features of Wasgamuwa is the incredible diversity of its flora and fauna, which is exquisitely unique with a high endemicity and most of the island’s large and small mammals inhabiting the region. The occurrence of diverse habitat types in Wasgamuwa is one of the primary contributing factors to the high diversity and uniqueness of the region’s wildlife. Wasgamuwa is also an important bird area. Interestingly, the name “Wasgamuwa” is derived from the past when this entire region was known as “Walas Gamuwa,” the land of the bear.
Besides conducting research on human elephant conflicts and developing sustainable measures for its mitigation, we want to understand the rich biodiversity in the region and identify current threats to help in their protection and conservation. With the issue of human-elephant conflict making the headlines, the conservation status of other wildlife in the island is often overlooked. This is rather unfortunate since Wasgamuwa is one of the few places in Sri Lanka where you can observe all the mega carnivores and herbivores in the country. Furthermore, almost all our mesocarnivores such as civets and mongooses also inhabit forests in Wasgamuwa. Apart from one scientific research project conducted in 2003 on the sloth bear, no other research has been conducted since then and very little is known about the carnivores in Wasgamuwa.
The biggest challenge to studying terrestrial mammalian carnivores in Sri Lanka is that they are elusive. Almost all of them are mostly nocturnal and solitary in their habits. In 2005, we made an effort to assess the forest reserves in Wasgamuwa for the presence of leopards by using remote cameras. The fact that even with definite physical signs such as scat, pug marks, and scratch posts quite evident, not one animal was recorded by the cameras. This fruitless effort was called The Pooping Ghost Project. The name aptly reflecting the frustrations we felt since we frequently encountered fresh piles of scat giving evidence to the presence of leopards but we were unable to get one photograph for visual confirmation.
Adding to the challenges was the prevalence of poachers which resulted in the theft of nearly 80 percent of the cameras due to which the project had to be abandoned.
A renewed effort was made ten years later in 2016 with the main objective being to collect ecological data on the leopards in Wasgamuwa using remote cameras. This research is done in collaboration with the Department of Wildlife and Conservation and we are also supported by Dr. Anthony Giordano of the Society for the Preservation of Endangered Carnivores & their International Ecological Study (S.P.E.C.I.E.S.) based in the USA.
Remote camera traps is one of the most effective and non-invasive tools conservationists and scientists use to obtain information about wildlife. Camera traps help scientists to collect a wealth of data on the presence, demography, habitat use, different behaviours and threats to rare and threatened species around the world that are not easily observable in the wild.
Unlike the leopards in Yala and Wilpattu, the leopards in Wasgamuwa are very elusive and getting scientific data through direct observations is impossible. The use of remote cameras has helped to overcome this challenge and allowed us to collect a wealth of information about leopards, other carnivore species and animals in Wasgamuwa.
In 2017 with the permission and in collaboration with the Department of Wildlife Conservation we deployed a range of remote camera traps inside the Wasgamuwa National Park and in the forests outside the park. Over a period of 12 months we set up 85 camera stations mainly in the southern and eastern areas of the National Park covering an area of 85.5 square kilometres. This is approximately one quartre of the total area of the park which is 393 square kilometres in extent. In the area outside the national park we set up 17 camera traps in an area covering 3.5 kilometres of disturbed habitat that is frequently used by people.
Our total camera effort in the first year was 2662 camera trap days capturing 234 leopard images in total, which makes it one of the most rigorous camera trapping research efforts in Sri Lanka. While we are still in the process of analyzing this data with the aid of image analysis software the preliminary findings are amazing!
In a highly disturbed habitat that is 3.5 square km in area and located outside the Wasgamuwa National Park there are two males and four female leopards. This is an area that sees frequent human traffic both vehicular and pedestrian and yet there are six leopards inhabiting this area. Through our research we are seeing how versatile and adaptable leopards are. Some of our cameras have captured leopards on the very edge and in human dominated landscapes avoiding humans effectively as they occupy such marginal habitats.
Inside the park in an 85.5 square km area there are 14 female leopards and seven males. Our initial analysis shows the leopard density in our study area is similar to that in other national parks where leopards live in relative protection. It could be assumed that there is a fairly healthy population living in Wasgamuwa at least in the areas we are monitoring with remote cameras.
In addition to our camera trapping effort we aim to scientifically study the foraging ecology of leopards by analyzing their scat. This will help us to systematically understand the ecology of leopards in Wasgamuwa and threats to their survival including parasitic infestations and diseases that afflict them which will help us to develop effective measures for their conservation and management.
During the first year of the project in addition to leopards we were able to capture 30 species of mammals. We were able to gather substantial information on the Sloth Bear and on the three small wild cat species: Jungle Cat, Fishing Cat, and the Rusty-spotted Cat. Our camera traps have recorded all three species giving us very useful information and insights into their lives.
Another species of concern is the pangolin. According to our findings, the pangolin is one of the species most targeted by poachers. We have frequently encountered campfires deep in the forests where pangolins had been butchered and consumed by poachers, their scales scattered on the forest floor. Again the cameras are providing us valuable information on the habitat selection of pangolins and threats to their survival.
Camera trapping is a very exciting research technique yet there are some serious challenges to using them effectively. One of the main issues is losing valuable cameras to poachers who come into the national park and outlying forests to hunt illegally. Poachers destroyed or stole nine cameras last year and are a threat to our own safety as well since they are armed and also set trap guns in the jungle. Elephants are another huge challenge—they destroyed eight cameras at the beginning of our research. But we have found an effective solution for that.
In our second year our aim is to find out the density of leopards in the Wasgamuwa National Park. In order to do that we will set up paired camera stations on well-used travel paths of leopards which we had identified last year. We will adopt the spatial capture-recapture model (SCR) with individual level identification to get very accurate density information.
The current perceptions people have about leopards are mostly centred on human–leopard conflicts due to a few scattered incidents that had received wide media coverage. While it is important to look into these incidences—conflict mitigation is just one aspect of conservation and there are other major components of conservation that need to be addressed. To do so we need empirical information such as base line ecological data especially related to habitat requirements and prey base of leopards. In reality human-leopard conflict is less of an issue at present especially considering that our research is showing how leopards are living in close proximity to people. Illegal killing of leopards is another serious threat about which very little is known. Our cameras are providing us with some of this base line ecological data and this information would help us to take conservation actions accordingly such as protecting habitats and prey species that are critical for the conservation of leopards in Wasgamuwa.
The Sri Lanka Wildlife Conservation Society has been implementing practical community-based conservation measures for two decades. Adhering to the conservation philosophy we follow, that we need to work with communities and they must benefit from our research and conservation efforts—the SLWCS is now reaching out to these communities—especially those who have leopards practically living at their doorsteps, to establish conservation measures which would generate benefits to them as well to the leopards.
For more information, please see Lanka Wildlife Conservation Society (slwcs.org)