Big cat finds a home along closed trail
Rio Grande Trail guardians received unexpected help keeping intruders out of a section of the path that was closed for the winter to benefit wildlife.
A female mountain lion and her juvenile have prowled the section between Catherine Store and Rock Bottom Ranch throughout the winter. They have been captured on motion-sensor cameras erected by the Roaring Fork Transportation Authority to track activity in the closed stretch.
Jonathan Lowsky, a wildlife biologist who is helping RFTA monitor wildlife conditions along that sensitive stretch of the Rio Grande, saw tracks that showed the female ambushed an elk calf. The big cat’s tracks show she leaped from a vantage point, bounded off the top of a wood rail fence at Rock Bottom Ranch, then caught and killed the elk calf. After feeding herself and her cub, the cougar hid the carcass in a hay feeder at the ranch, Lowsky said. Pictures show the calf’s ears poking out from under the hay the cougar used to hide the body.
The elk calf was picked to the bones in three days, Lowsky said. Cameras show the juvenile made more trips back to feed than the mother.
“I think that female has been there a very long time,” Lowsky said. In the winter of 2008, she raised two cubs. It is likely it is the same female because she appears healthy, strong and capable of defending her territory. “She’s been able to successfully produce offspring the last few years,” he said.
His research books said females send their offspring packing after 12 to 22 months. The young cats must go out and establish their own territory.
The Rio Grande corridor provides high-quality habitat with abundant deer and elk. Mountain lions are pouncing predators that like to jump off rock outcrops onto their prey. The area provides ample opportunity, Lowsky said.
When RFTA developed the Rio Grande Trail through the area late last decade it agreed to a closure from Dec. 1 to April 30 to minimize disturbance to wildlife. Lowsky said RFTA deserves credit because the closure makes that roughly 2-mile stretch even more attractive to wildlife than it was before the trail was developed. The corridor was open to anglers and hikers during winters.
“It’s essentially become a winter wildlife refuge,” Lowsky said. “It’s always a good indicator when the top predators are behaving in a natural manner. The ecology of that area is functioning.”
The ecology isn’t perfect because it never can be in a developed area, he added. But the species range from voles, at the bottom, to top predators like mountain lions, golden eagles and bald eagles.
The motion-triggered cameras have captured images of bears, coyotes, bobcats, wild turkey, geese walking down the trail, and lots of deer and elk, including some showing scars that indicate they tangled with mountain lions, Lowsky said. The claw marks were visible.
Humans have been absent from the images. Mike Hermes, RFTA director of facilities and trails, wrote in a memo that there is little evidence that humans are poaching the closed section of trail this winter. “Violating the closure this year may prove dangerous!” he wrote, noting the presence of the big cat.