What is a Bobcat?
Bobcats are small wild cats with the scientific name Lynx rufus. They get their common name because of their short bobbed tail, while their scientific species name rufus refers to their brown coat coloration. They greatly resemble Canadian Lynx (Lynx canadenses), and are very closely related to lynx. However, they are different species of wild cat, and canadian lynx and bobcats overlap in geographic distribution in only a few areas. Lynx tend to thrive more in environments with snow because they have large, plate-like feet that act like snowshoes. Bobcats, however, don't have the big feet well-adapted to snow and so are out-competed by lynx in areas where their distributions overlap. Bobcats are more widely geographically distributed than lynx and are adaptable to many environments and are found in deserts, swamps, forests, and even urban environments (see www.nps.gov/samo/naturescience/Bobcats.htm) just to name a few.
Bobcat Geographic Range
Bobcats are the most widely distributed wild cat in North America. They are also found in Southern Canada and in parts of Mexico. Given their wide distribution, they are not considered endangered species. It is even legal to trap bobcats for their fur in many parts of the United States, including California.
Bobcats are strict, but generalist, carnivores. This means their diet is entirely made up of other animals, but they are known to eat many different animals. Bobcats seem to primarily eat small mammals, but are also known to eat birds and reptiles, and even deer when they are lucky. They are known to eat deer primarily in the northeastern part of their range, and generally the deer are young or females. The small mammals bobcats typically eat include rabbits, woodrats, squirrel, voles, gophers and varies depending on what lives where the bobcat lives. In Southern California, Fedriani et al. (2000) foundthat the bobcat's number one food choice were rabbits. The 3 other most popular food items were gophers, ground squirrels, and woodrats.
Video provided courtesy of Barry Rowan, an Urban Carnivores collaborator who documents wild bobcat behavior through photos and video in Santa Barbara area.
Bobcats tend to be primarily nocturnal creatures, particularly near urban areas where they actively attempt to avoid crossing paths with humans. They are solitary creatures, like all wild cats with the exception of African lions and young male Cheetahs. Bobcats are territorial, and the areas each individual occupies is called their 'home range.' Male home ranges will overlap several female home ranges and it is thought that the males will primarily mate with those females within his home range. Males try to maintain distinct home ranges from other males, and females try to keep separate, non-overlapping home ranges from other females. To do this, both sexes are known to mark their territories with scrapes, scent, and scat.
Here a bobcat displays his territory marking behavior, captured by Laurel Serieys as part of her bobcat research. Check out this video captured near Topanga State Park- part of the Santa Monica Mountains!
Bobcat Home Ranges
Bobcats, as mentioned above, are solitary creatures. They are also territorial, and establish what is called a "home range." This refers to the area that a bobcat routinely uses. Both males and females establish home ranges. The male homerange is generally larger than the females, sometimes more than twice the size of a female's range! There is a lot of variation in home range size depending on the geographic region. A good rule of thumb is that in the southern end of the range of the bobcats, the home range is smaller than on the northern end of the range. For example, Litvaitis et al. (1986) found that male bobcats in Maine had home ranges of 71 square kilometers, while females had home ranges of 32 square kilometers. In Alabama, on the other hand, the male home ranges were 2.6 square kilometers and the female home ranges were 1.1 square kilometers (Bailey, 1974). Obviously there is a lot of variation, and one factor that may affect home range size could include bobcat population density (Benson et al., 2006). When population density is high (ie., when there are a lot of bobcats in a given area), the home ranges will be smaller. In Southern California, in our urban Thousand Oaks study area, home range sizes for males averaged 7.1 (about 4.5 square miles) square kilometers, while it was 3.5 square kilometers (about 2.2 square miles) for females.
Males tend to overlap 2-3 female home ranges. Females establish their own home ranges that tend to exclude other females, and males establish home ranges that tend to exclude other males. We believe that during mating season, the males will mate with the females encompassed within his home range. We are presently analyzing genetic data for our bobcats that we have captured and radio-collared in the Thousand Oaks area. These analyses will inform us of if males are mating with the females encompassed within their home ranges, and also if for female bobcats that have home ranges that overlap somewhat, if those females are related.
Female bobcats can breed during their first year (9-12 months old), though this rarely occurs. Males are sexually mature at 2 years of age. Bobcats have mating 'seasons' and birthing 'seasons.' Bobcats, as mentioned above, are solitatary creatures. So, bobcats have to have a way to communicate with one another to find eachother and mate!
In Southern California, bobcat maiting season is in the winter, generally starting around December, lasting through January and potentially into February. Our experience has been that it is much easier to find bobcat sign during the mating season. The males especially leave scrapes on their trails that they spray with urine or also mark with scat.
Once the female is pregnant, the gestation period is 60 days. She will typically have litters of 2-4 kittens, but in the Santa Monicas, we recently had a female with a litter of 5 kittens! And all 5 kittens survived their first year! The female will have her kittens in a den that she has found, and then she will stay with her kittens in the den for a few months, rarely straying far from the den site. The den is not something she constructs herself, but a spot she considers safe and hidden for raising her kittens.
Local Bobcat Research
The National Park Service has studied bobcats in the Santa Monica Mountains since 1996. Most of the research has been focused on populations around Thousand Oaks and Agoura Hills regions. Since the study began in 1996, 281 animals have been humanely captured (see 'Research Methods' page for more information), tagged, and samples collected. Many of these animals have a
lso been radio-collared in order to study their movement patterns. The general goal of National Park Service research on bobcats has been to understand how urban development affects the ecology of this charasmatic species. Since 2008, research efforts on bobcats have expanded by both National Park Service biologists and collaborating UCLA biologist and graduate student, Laurel Klein. Expanded efforts allowed us to increase our study areas. National Park Service biologists are now also studying bobcats in Point Mugu State Park and the Calabassas area. The UCLA study expanded humane trapping efforts to include Topanga State Park, Malibu Creek State Park, and areas east of the 405-freeway such as Beverly Hills, Bel Air, Hollywood Hills and Griffith Park.
A Few Quick Facts About Our Local, Santa Monica Mountain, Bobcats
1. The largest bobcat we have captured (of 292 since 1996) was 11kg. That puts him at 24.2 pounds. We believe that this is the upper limit of the weight of our bobcats locally.
2. Bobcats only eat meat and locally prefer to eat rabbits, ground squirrels, gophers, and woodrats.
3. Bobcats are solitary and territorial.
4. Male homeranges are around 2 square miles, while the female homeranges are around 1 square mile.
5. Bobcats will cross secondary roads (ie., smaller than freeways), but are less likely to cross freeways regularly.
6. Bobcats are susceptible to the same diseases as a domestic, pet cat is, and disease can be transmitted between a domestic cat and a bobcat (or vice versa). This is just one reason to keep your pet cats indoors.
7. The biggest threat to our local bobcat populations is rat poison exposure, and a possible link between rat poisons and a disease, notoedric mange, that usually is not harmful to wild cats.
8. Bobcats may be exposed to rat poisons starting before they are born and for the duration of their lifetime. They are exposed because people use the poisons in a variety of urban settings such as in and around the home, at schools, watershed areas, parks, golf courses, landfills, commercial buildings, etc.
9. Bobcats locally have never been documented to eat people's pets or attack people.
10. Bobcats in our area tend to avoid human interactions.
11. Bobcats usually have 2-4 kittens in a litter sometime between February and June each year. The mom raises the kittens alone.
Bailey, T.N 1974. Social organization in a bobcat population. Journal of Wildlife Management, 38: 435-446.
Benson, J.F., Chamberlain, M.J., and Leopold, B.D. 2006. Regulation of space use in a solitary felid: Population density or prey availability? Animal Behaviour, 71: 685-693.
Fedriani, J.M., T. K. Fuller, R.M. Sauvajot, and E. C. York. 2000. Competition and intraguild predation among three sympatric carnivores. Oecologia, 125: 258-270.
Labisky, R.F., Boulay, M.C. 1998. Behaviors of Bobcats Preying on White-tailed Deer in the Everglades. The American Midland Naturalist, 139(2): 275–281.
Litvaitis, J.A., Sherburne, J.A., and Bissonette, J.A. 1986. Bobcat habitat use and home range size in relation to prey density. Journal of Wildlife Management, 50: 110-117.