Since 2002, WCS has been using camera trapping to survey the leopard population over a significant portion of its range. Camera trapping allows us identify individual leopards by their unique spot patterns, and therefore we are able to monitor individual animals over many years, estimate population density and trends over time, and learn about rates of population turnover.
On a cold but bright and sunny day on 28th of January, tracks left in the snow by a female leopard lead us to the bottom of a steep slope and a clump of deer hair. We looked above us and saw a drag-line up the slope, the leopard had evidently pulled the deer kill up the rock-face. As we ungracefully scrambled up the snow-covered slope, grappling hold every tree to pull ourselves up, we admired the strength of the leopard required to pull a dead weight of at least 45 kg. After twenty metres we came to a rocky outcrop secluded by a fallen tree, an ideal spot for the leopard to hide the kill from scavengers. Indeed it was here that we found the remains of a young adult female sika deer. We immediately noticed that there was still some meat left on the carcass and therefore she was probably in the area resting on a full stomach, but she could return to continue feeding at anytime. Hoping that she would return to the kill, we quickly and quietly set up a camera trap. These cameras are fitted with a motion sensor, when triggered (by a passing animal for example) the camera automatically takes a photo. We wanted to confirm the sex of the leopard and compare photos with other leopards taken during our annual camera-trap survey – was this a new leopard in the area?
Six days later we returned to collect the camera. Once we got back to the kill site we saw that our clamber up the slope was not in vain. Only the legs were leftover, the rest of the carcass had been eaten or dragged elsewhere. Something had been here at least, but was it a leopard? We could hardly wait to get back to the base and download the photos to find out.
Sure enough, we had lots of photos of a female leopard, she returned to feed on 29th of January at 11.30am and spent one hour feeding from the carcass. It was reassuring to see that she looked in good condition – even in mid-winter, undoubtedly the hardest time of the year. From the individual spot patterns we were able to identify her as leopard number 27, seen in our camera-trap survey since 2008. There were also other visitors to the kill including crows, a golden eagle, two black vultures and a Siberian weasel. With this one kill leopard # 27 not only fed herself but also a multitude of forest denizens.
Not only is it rewarding for us to see images of these remarkable animals in their natural environment, but it also shows us how valuable snow-tracking is. We will continue to gather crucial evidence about the behaviour and movement patterns of leopards and tigers in our study area. By answering questions such as what areas of the landscape they avoid, what habitat features they need to persist and the prey species they rely on we are in a better position to formulate conservation strategies for these species to ensure their future for generations to come.
To learn more about WCS research of Far Eastern leopards in Southwest Primorye, click here.