Spot that leopard!
Today’s guest blogger is Lucy Hughes. Lucy lived and worked on a private nature reserve in South Africa for four years, carrying out field research that included a camera-trap study into the reserve’s leopard population and twice monthly bird surveys for Cape Town University’s Birds in Reserves Project (BIRP).
Trying to discover how many individual leopards used a reserve in South Africa was challenging work in more ways than one. Unlike the Serengeti Lion Project’s (SLP) 200-odd camera traps, I could count ours on one hand. That said the study area was much smaller at around 2,500 hectares. The technique was also very different. Whereas the SLP is trying to get a snapshot of animal interaction over a vast area I was interested in individual animals, so setting the camera traps up systematically on a grid basis was not the best option. Instead, to make best use of our limited camera traps, I selected sites that I thought a leopard was most likely to pass.
These sites fell into two categories, the survey sites and the random event sites. Based on recent tracks and scats on game trails and roads, the cameras were moved around the reserve on a regular basis in an attempt to survey the whole area. One or two cameras were reserved for the random events: a fresh kill, old carcass, or hunches about certain water holes or koppies (rocky hills).
My job was to trundle around the reserve, mostly on foot, searching for signs of leopard. Looking for tracks and scats on the network of sand roads was easy and for the most part it seemed these big cats do love a nice clear road to walk down. Wandering down a dry river bed following a set of tracks idly wondering if the leopard is asleep in one of the big Marula trees is one thing, but suddenly realizing that the pug marks seem to have doubled in size and that you are hot on the trail of two lions jolts you to a stop. Finding signs off these roads was a little harder, the substrate of the game trails was often tangled with grasses and small thorny bushes and picking up tracks was virtually impossible.
Half an eye was always on the sky watching for vultures. Their activity often led to carcasses but it was the sense of smell that served best. The smell of rotting carcasses is fairly potent and travels far and my nose became super sensitive to the whiffs. Unfortunately not having the skills of a bloodhound I would flounder around in the bush turning this way and that trying to pin down the source of the smell.
Other than spending just a little too much time around dead things, camera-trapping carcasses lead to some great data. One surprise was just how often kills seemed to be ‘shared’. The following two shots from the same eland kill highlight this. You can see even without comparing spot patterns that these two leopards are different.
The first is a young female and the second is the reserve’s dominant male so it’s hardly surprising that he has stolen her meal. At other kills, though, we had various combinations of leopard visitors including three different adult males within two nights to the same zebra kill. The fact that the leopards stayed put in front of the cameras, munching, meant we managed to get shots from every angle, which helped a lot in putting together ID charts. At no time did we tie down any of the carcasses so clearly the leopards where not fazed by the cameras.
This following shot shows a jackal at the same eland kill. The leopards on this reserve where under very little pressure from lions, which only passed through occasionally. They hardly ever resorted to stashing kills up trees as leopards in areas of high lion density would.
This meant that many smaller mammals took advantage of the leftovers. Other than the obvious spotted hyena, we recorded brown hyena, side-striped and black-backed jackal, honey badger, civet, bush pig, and mongoose. This following shot looks harmonious, but the series shows that the honey badger definitely had the upper hand on the jackal.
The one thing that fellow researcher, Michele, and I were always aware of was that we were spending a lot of time in places that big cats also spent a lot of time. When you are setting up a camera on a fresh kill you can’t help but wonder if the killer is laying somewhere close watching you!
Check out the time stamps on this next set of pics to illustrate this point!
Photos copyright Michele Altenkirk/Lucy Hughes, Lisssataba NR