Colorado’s lynx
back from the brink?

by Michelle Butzke

The Colorado Division of Wildlife’s (CDOW) lynx recovery team is experiencing a remarkable year. Major milestones and minimal setbacks have made 2003 a very satisfying year of research for the group, now in its forth year.

This spring, the tracking team discovered six dens and sixteen lynx kittens while monitoring the research area in southwestern Colorado. This is the first time kittens born from released lynx have been documented. The research group discovered the dens while monitoring female radio collar activity. Long periods of stationary signals clued the researchers that the female lynx had most likely settled in  to a den to bear young. Researchers were not disappointed with the findings. Scattered throughout rugged, rocky slopes and cliffs littered with fallen timbers above 10,000 feet, the lynx dens were calculatedly created by the lynx females in areas with large populations of snowshoe hares, the lynx’s favorite prey.

All sixteen kittens were photographed, tagged, and studied with minimal time spent away from the mother. Mother lynx cats remained close to researchers during the examinations and returned to the den after researchers left. So as not to disturb the mothers and kittens further, the lynx recovery team will not attempt to visit the dens again until this fall.

Researchers are not sure why it has taken four years to see released females reproduce. Most assume that it has taken a few seasons for the cats to develop their territory and become comfortable with the habitat they now live in. Whatever the reason, the births come as a great comfort to the hundreds of individuals who have worked thousands of hours on the lynx reintroduction effort.

Although the research team can breathe a sigh of relieve that repopulation is occurring, the real test is about to begin. “We still cannot call this a successful reintroduction. In fact, we may not be able to for as long as a decade,” said Todd Malmsbury, chief of information for CDOW’s lynx recovery team. “These kittens must live to maturity and reproduce themselves. The lynx population must have a recruitment rate higher than its mortality rate in order for this reintroduction effort to be called a success.” Recruitment is the term that researchers use for the successful reproduction, rearing, mating and subsequent reproduction of released animals.

The team first released lynx in 1999. Since then, a total of 129 lynx have been released into the rugged terrain of southwest Colorado, with forty-six deaths recorded. However, mortality rates seem to be on the decline. Only one lynx death was recorded by researchers this year. Although the death is a disappointing discovery, it is a minimal setback, considering that twenty five deaths were recorded during the first year of the lynx re-introduction. Causes of lynx death vary from starvation and predators to shootings and vehicle hits, but the cause of the 2003 death was unknown.

CDOW plans to release as many as 130 more of the big-footed cats before 2007.

Big paw prints:
Lynx, bobcat or lion?

Lynx are very similar to bobcats: they are both about the same size and have ear tufts, facial tufts and a short tail. However, bobcats generally have distinct striping on the front legs and faces, while lynx do not. Also, the lynx tail is completely black, whereas the bobcat tail has a black spot on top and is white beneath. Footprints in the snow are the best clue to determine what cat you are tracking. Lynx feet are huge and out of proportion with their small bodies, but the large feet make them exceptional hunters when on snow (think snowshoes). The prints are typically five inches across (about the size of a man’s hand) whereas the bobcat print is only two to three inches across. Mountain lion have large prints that may look similar to the lynx print.

Two clues can help determine whether you are in a lynx or lion area: the lion tracks are generally more distinct around the toes, while toe pad prints of the lynx usually aren’t visible because of the fur that lynx have on their feet. Secondly, the stride of a mountain lion (about twenty inches) is significantly longer than that of a lynx (about thirteen inches).

Join the team

The lynx recovery team frequently employs individuals to assist with the winter tracking efforts. Individuals must be fit, energetic, and have extensive backcountry experience. Lynx tracking is a paid position and generally requires the person to work and/or hike extensively each day for six months. If you are interested in joining the lynx recovery team, please contact Tanya Shenk, Ph.D., lead lynx researcher at the CDOW via email, tanya.shenk@state.co.us. P