I've been studying how urbanization affects the health and disease susceptibility of bobcats in and around the Santa Monica Mountains since 2006. This work has involved capturing bobcats to collect samples from them. I've been fortunate to not only maintain my own trapline for this effort, but to collaborate with the National Park Service to get samples from the animals they trap for their own ongoing long-term bobcat research. From 2009-2011, I intensively trapped bobcats for nearly the entire two years (taking breaks only during kitten season when females could have young kittens to tend to). Because of this work, I've been blessed to have handled at least 100 bobcats, and have myself trapped approximately 60 individuals. In addition to the bobcat work, I've aso been fortunate to collaborate on the National Park Service mountain lion project, also in the Santa Monica Mountains. I've not seen nearly as many mountain lions as bobcats, but working with both species, I've learned important techniques for trapping and handling cats.
When describing my work to both scientists and nonscientists alike, most people first ask how we catch the cats to get the samples. So I thought it would be a good blog topic- or topics. Its a multistep process, so for this entry, I'll focus on the first step- figuring out where the cats are so we know where to put our traps! *(See note at end of entry about trapping ethics)
Diving into how to catch a cat...the first step is figuring out where the cats are! There's a couple ways to do this- when working in a new study area where it is unknown whether your species of interest is present, biologists may set up remote wildlife cameras to determine what species live in the area. For example, when National Park Service biologists started their mountain lion project in the Santa Monica Mountains in 2002, they had no idea whether there were even mountain lions in the Santa Monicas! Mountain lions are found throughout California but they are very sensitive to urbanization and habitat fragmentation. So in areas where there is a lot of habitat fragmentation and urban development, there may be areas of "local extinctions" where populations are unable to survive longterm and their populations go "extinct" in a localized region. Given that the Santa Monicas are next to one of the largest cities in the world, its not stretch to imagine that it would be difficult for a healthy mountain lion population to persist in the region! So, to discover if mountain lions were even still present in the Santa Monicas, NPS set up heat-triggered remote wildlife cameras around the Santa Monicas where every time an animal walked by the camera, a photo would be taken. It was using this method they discovered that there were mountain lions in the park!
Another method is to get out in the field and look for animal tracks and sign. Every species of animal has a distinctive track and many have distinctive fecal material (also known as "scat"). Some animals (like bobcats or mountain lions) mark their territory with distinctive scrapes on the ground. The scrapes for bobcats and mountain lions look very similar, but mountain lion scrapes are much larger than bobcats! So, as a local carnivore biologist, I've learned some distinctive signs (scat, tracks or scrapes) for fox, mountain lion, coyote, skunk, and raccoon. Using both this method of looking for animal sign, along with the remote cameras, is useful to not only identify what animals live in an area, but also learn what are common paths that animals use. Knowing the best paths is the next step to knowing how to catch a cat! My next entry will focus on choosing a trap site, so keep posted for that!
*An important note- we (myself along with my National Park Service collaborators) do not take trapping and handling animals lightly. When trapping and handling animals, it induces stress in the captured animals and there's always a risk that something can go wrong for the animal or the biologist. For projects that involve this invasive techniques, we must have our protocols reviewed by animal ethics committees and weigh the cost of stressing an animal with the benefit of the research where the benefit must outweigh the cost.