Kittens Buoy Colorado Lynx Reintroduction Efforts
By Leland Rucker
DENVER, Colorado, May 28, 2003 (ENS) - Two lynx kittens found huddled with their mother on a rugged hillside in Colorado's remote San Juan Mountains have rekindled hope that the state's efforts to reestablish the reclusive cats will be successful.
A second set of kittens was confirmed by wildlife biologists Thursday at 11,200 feet, the highest lynx den ever found in North America.
"In a word, our biologists were ecstatic," said Todd Malmsbury, spokesman for the Colorado Division of Wildlife (DOW). The two kittens represent the first documentation of offspring since the state first began introducing Canada lynx into the state's southeastern mountains beginning in 1999.
Using radio signals, state biologists found nine lynx pairs during the spring breeding season, which extends into June, Malmsbury said, adding that they are hoping to see other kittens.
"We have worked so hard for four years to reach this goal. We've seen them establish territory and find prey. We've seen males and females together, but we've not seen reproduction. This is an enormous juncture, but there's so much more to do," Malmsbury said.
Rob Edwards is director of carnivore restoration for Sinapu, a Boulder based organization dedicated to restoring predators to Colorado that has supported DOW lynx reintroduction efforts. "I think we have a lot to be proud of to date, especially the work of the biologists on the ground that are making it happen," Edwards said. "They deserve a tremendous amount of credit."
Lynx are medium sized carnivores, about 20 to 30 pounds. Their distinguishing characteristic is their feet, which are huge in comparison with the rest of their bodies. A lynx track can be five inches across, the size of a female mountain lion's track.
Lynx are normally secretive and avoid contact with humans. Their primary food source is snowshoe hares, abundant in Colorado's high country, but they also prey upon mice and voles, ground squirrels, red squirrels and cottontail rabbits, Malmsbury said.
The lynx was listed as a Colorado Endangered Species by the state Wildlife Commission in 1975, six years after the last verified trapping of a lynx near Vail. In 2000 it was listed as "threatened" by the U.S. Fish & Wildlife Service in 14 states, including Colorado, the southern end of its historic range.
The Division of Wildlife released 41 animals captured and transferred from western Canada and Alaska into the San Juan mountains in 1999. Another 55 animals were released in 2000.
Of the 96 lynx released in 1999 and 2000, DOW statistics show 45 known deaths. Lynx have died from starvation and plague; they have been shot and have been hit by vehicles. The state wildlife officials are currently tracking about 63 of the 84 animals known to be alive.
The lack of hard breeding evidence has been frustrating. "We knew they were finding prey and cover and all the things they needed to survive," Malmsbury said. "We also needed to have males and females in the same areas. In some areas, there are females and no males. In others, it was vice versa. There was strong opinion among experts that we didn't have enough density to give reintroduction a fair shot."
To increase that density, an additional 33 lynx captured in Manitoba and British Columbia, were released in April, and future plans include the release of 50 more lynx in each of the next two years and up to 15 animals in 2006 and again in 2007.
The two kittens were found in prime lynx habitat on a rugged slope area at 10,600 with lots of downed timber. Malmsbury said. The mother and suspected father were released on April 2, 2000.
Scientists spent 11 minutes checking the cubs' condition, taking DNA samples and attaching ear tags to the cubs, who were estimated to be seven to 10 days old. The cubs and mother appeared to be in excellent condition. The kittens each weighed 380 grams and their eyes were still closed.
The mother remained in a nearby brush pile during the intervention, growling in a deep, low voice, and she joined the cubs after researchers left, Lead Researcher Tanya Shenk wrote in a field report posted on the website Tuesday. Shenk says that they will not disturb the den again this spring, although the mother's movements will be tracked by telemetry, and researchers will snow track the mother to find out if the kittens are still with her in the spring.
Sinapu's Edwards, citing recent Bush administration decisions that encourage logging interests and road building, says habitat protection is still the major concern for long term lynx survival. "The more roads we have per square mile, the less suitable habitat there is for animals, like the lynx, that are habitat sensitive."
Malmsbury says that other problems, like defining the cats' prey base in warmer weather when they cannot be tracked, wait to be solved. "But the big obstacle has been lack of reproduction. We've only seen two. We need to see a lot more reproduction."