Over the weekend, I went out with a couple friends, Tanner* and Johanna, to investigate what appeared to be a lion kill that Johanna stumbled upon the day before. Johanna and Tanner are citizen scientists, meaning that although not trained in biology, they have a keen interest in biology and desire to contribute to scientific research locally in southern California. Because of their passion for local wildlife and learning what they can about wildlife in their natural habitat, they spend most of their free-time hiking around various open spaces honing skills such as wildlife tracking and the use of remote cameras to study carnivore behavior. Their skills in tracking and remote camera use exceed those of many biologists I know, and every time I go out with them, I learn something new! So when Johanna stumbled upon a dead deer but was unsure how it died, I was only too eager to go check it out. The deer appeared have died at some point earlier in the week, but had no overt signs that something was feeding on it. One possibility, of course, was that it was killed by a mountain lion earlier in the week (though the there were not signs it was still eating the deer if that's what happened), and if so, this provided a potentially opportunity to gather mountain lion DNA (swab any bite marks or look for mountain lion scat that they sometimes leave at their kills). It is unusual for a lion to kill something and not feed on it, but not impossible for that to occur. I should clarify before continuing with the story- we did not expect to encounter a mountain lion, and if we believed there was a reasonable risk of encountering one, we wouldn't have revisited the dead deer. So, although we should all acknowledge that mountain lions live in our local State Parks and we should all act accordingly, we weren't out there to chase down a mountain lion.
So, we headed out to the Santa Monicas where Johanna found the deer, and where Tanner also happened to also have wildlife cameras as part of his volunteer work with the National Park Service. By time we got there, the deer's head was covered with maggots, and no bite wounds were visible either on the head or neck, so it remained unclear if a mountain lion was responsible for the death (although Johanna did get the pics below when she first discovered it, and no maggots were present).
However, Tanner happened to have a remote camera within 10 feet of the dead deer, but where the deer died was just out of the visual field of the camera. The camera still picked up some very interesting footage that provide some clues as to what may have happened. In the video, we see two deer startled by something out of view of the camera. The deer seem to be attempting to run from whatever startled them. Then, out of view of the camera, we hear loud breathing and a few grunts, presumably by the deer, or perhaps whatever startled it. The startled running combined with the sounds do lead me, at least, to believe that the deer was killed by a mountain lion. There was a patch of missing fur that seemed perhaps licked off by whatever killed it just under the left elbow of the deer (see photo). I did swab that region, so perhaps if the fur was licked off by a mountain lion, I will get DNA off the swab. If no DNA is present, perhaps this will remain a mystery forever! But check out the video footage and see what you think!
*Please note: Tanner is a volunteer with the National Park Service, and so the work he does with cameras in State Parks within the Santa Monica Mountains National Recreation Area falls under research permits conducted by wildlife biologists with the National Park Service.
In the previous blog entry, I was planning to conduct genetic analysis on the swab I took on the bare spot of the deer's hide. I wanted to know if a mountain lion had at least licked off the spot of fur- which could also suggest that a mountain lion killed the deer to begin with. Well, the results are in and indeed, it was a mountain lion that licked the bare spot of fur off. Not only that, it was a female mountain lion! There generally seem to be less evidence female mountain lions in the Santa Monica Mountains than males (although the documented ratio of males to females born in SAMO so far is about 50/50). So, finding evidence of a female mountain lion is very exciting, as well as getting a genetic sample!