Leopards can be among the most challenging animals to track in the wild. Elusive and shy, leopards are masters of disguise, often seamlessly blending into the background. Of the “Big Five” African animals (also including elephants, lions, rhinos, and buffalo), it is the one that most visitors to Africa never see. However, for their conservation, it is vital that we determine how many leopards exist in the wild—and in many areas, this information is missing. So, what is the best way to count leopards? [caption id="attachment_122517" align="aligncenter" width="2288"] An African adult male leopard gazes over his territory at Loisaba Conservancy. (photo: Dale Scott)[/caption] That is one of the questions we are trying to answer in a new conservation initiative at Loisaba Conservancy in central Kenya. We are using remote cameras to photograph leopards, and their unique coat patterns allow us to distinguish individuals. But it is not as easy as just setting up a bunch of cameras in the wild and hoping for the best. Researchers will often set cameras out in regularly spaced grids, with the idea of getting a sample of the animals that occupy the habitat. However, camera grids aimed at snapping pictures of secretive animals like leopards can suffer from low detection rates, and it can take many cameras operating for many days to get a sense of abundance. This can slow the time required to get an accurate population estimate—and increase the workload of sorting thousands of photos to find the few images of leopards. [caption id="attachment_122518" align="aligncenter" width="4480"] Nicholas Pilfold applies cologne to a scent pad, while Kenyan field assistant Ambrose Letoluai learns the method of application. Scent pads are also adorned with hair snares, to capture DNA from leopards that decide to rub. (photo: Megan Owen)[/caption] This year in Kenya, we are taking a different tack: luring leopards into getting their picture taken. To understand what might attract a leopard to our cameras, we turned to our resident leopard experts here at the San Diego Zoo: Gaylene Thomas, an animal care supervisor; and Todd Speis, a senior keeper. They told us that successful scent attractants for leopards include a variety of herbs—except catnip, ironically! Scents such as wintergreen and cinnamon, and colognes such as CK Obsession for Men also do well. So, given that advice, we headed to Kenya armed with colognes and essential oils—not the usual items one has for fieldwork. We are currently testing which scent lures work best to bring leopards out from hiding and have them linger long enough to get good camera images of coat patterns. [caption id="attachment_122516" align="aligncenter" width="1698"] Wildlife cameras deployed by San Diego Zoo Global researchers capture an image of a male leopard on June 30, 2017 (left). After comparison, it was determined that this male was the same one that a tour guide photographed on his cell phone on June 10, 2017 (right). The red boxes indicate characteristic coat markings that are unique to this leopard. (photos: Nicholas Pilfold)[/caption] The initial results are promising, as our cameras are already getting images of leopards and identifiable coat patterns. For example, one of the tour guides at Loisaba Conservancy took several pictures of a male leopard making a stunning daylight kill—and when we began to examine the first sets of images from our cameras, we noticed an exact match in coat pattern on the left flank. Not only will coat pattern recognition allow us to track leopards across space and time, it also provides the opportunity for citizen science. With the high-powered cameras that many tourists carry, we are now initiating a sharing platform for tourist leopard photos at Loisaba Conservancy, so that we can maximize our detection of these elusive predators. Nicholas Pilfold, Ph.D., is a postdoctoral associate in Recovery Ecology at the San Diego Zoo Institute for Conservation Research. Read his previous post, Keeping an Eye on Polar Bear Maternal Dens.