Biologists in Colorado have been encouraged by the increase in the lynx population this year, after finding the first newborns documented since 2006:

DENVER (AP) The discovery of 10 lynx kittens in Colorado this spring after finding none the last two years and the location of some of the newborns outside what’s considered the cats’ core area have raised the hopes of biologists overseeing restoration of the long-haired mountain feline to the Centennial State.

The seven male and three female lynx kittens found in five separate dens are the first newborns documented since 2006.

“This was very, very good news,” said Tanya Shenk, the lead researcher for the Colorado Division of Wildlife’s lynx restoration program.

A total of 126 kittens are known to have been born in the state since biologists began releasing lynx trapped in Canada and Alaska in southwest Colorado. The tuft-eared cats with big, padded feet, good for maneuvering on snow, were native to Colorado but were wiped out by the early 1970s by logging, trapping, poisoning and development.

Biologists think a drop in the number of snowshoe hares, the main food source for lynx, might have contributed to a decline in kittens the past two years. Shenk said a study of snowshoe hares showed high densities in 2006-2007 and low densities in 2007-2008.

A milestone for the restoration program occurred in 2006 when Colorado-born females started reproducing. This is the first year that biologists found kittens whose parents were both born in Colorado. Biologists made the determination using data from the adults’ radio collars.

“It’s certainly another one of those positive signs,” Shenk said of Colorado-born cats mating.

Another encouraging sign is that two of the five dens with kittens were north of what’s considered the core lynx area, southwest Colorado. Lynx released in the state’s rugged San Juan Mountains have roamed into neighboring states. Shenk said finding kittens in other areas shows that they are comfortable enough to reproduce outside the core habitat.

Division of Wildlife lead biologist Rick Kahn said the agency is close to achieving all its goals for lynx restoration.

” We are very encouraged by the results this year and are hopeful that these animals will contribute toward a sustaining population for Colorado,” Kahn said.

The Denver-based conservation group Center for Native Ecosystems said the existence of dens farther north shows the prevalence of suitable habitat and prey in the state.The group is one of four suing to force the federal government to designate more land in the region as critical habitat for lynx, listed as threatened on the endangered species list.

Federal officials said they didn’t set aside any habitat in Colorado because the state’s lynx program had not produced a self-sustaining population. The designation can trigger additional protections for a species.

A total of 218 lynx from Alaska and Canada have been released in Colorado since 1999. No transplanted cats have been released in the state for the past couple years.

Biologists don’t know how many lynx are in the state. They’re currently monitoring 49 lynx with working radio collars, but many of the original collars have stopped working. Most of the kittens born in Colorado haven’t been fitted with transmitters.

Because Colorado was at the southernmost tip of the cat’s historic range, critics questioned the wisdom of trying to restore lynx to the state. The criticism grew louder when four of the first five lynx released starved to death, prompting immediate changes in the procedures.

Instead of releasing the lynx immediately, biologists kept them caged for about three weeks to fatten them up and freed them later in the winter when prey is more available.

In 2000, just one of 55 lynx died of starvation. That strengthened biologists’ belief that southwest Colorado mountains are good lynx habitat.

[LINK: LA Times; PHOTO: Colorado Division of Wildlife]