Links Between Lynx Are Closer Than Expected
A new study of lynx shows that isolated populations of the tuft-eared wildcat are genetically very similar despite being separated by thousands of miles.
The finding suggests that because the threatened species wanders thousands of miles to breed, government-sponsored programs to reintroduce it in western states do not have to rely on capturing animals with specific bloodlines to successfully repopulate an area.
Genetic evidence analyzed at the University of Montana suggests that every 10 years or so, lynx from as far away as northern Alaska tend to breed throughout the Canadian Rockies and into the northwestern United States.
Previously, scientists were split over the belief that lynx populations did not widely mix and were highly adapted to local environments.
The lynx study appeared in the Jan. 31 issue of the journal Nature.
“A lynx is a lynx is a lynx,” said University of Wyoming biologist Steven Buskirk, who did not participate in the study. “They are very similar across their geographical range.”
In the study, the Montana researchers mapped lynx populations from northern Alaska through western Canada and into Montana and Washington state.
Genetic analysis of lynx from 17 collection sites showed the animals did not vary significantly over distances up to 1,860 miles apart.
Radio tracking showed lynx regularly travel hundreds of miles to hunt and breed, often across glaciers and other forbidding natural barriers. They tend to roam even more than bears, wolves or coyotes, they said.
The researchers recommend that conservation efforts focus on preventing roads and development from pinching off the wild corridors that the lynx use to wander.
“Gene flow for the lynx is the highest yet found for any carnivore,” said the study’s lead author, Michael Schwartz. “Joint international efforts should be initiated to ensure that connectivity between northern and southern lynx populations is sustained.”
However, the finding doesn’t mean that lynx populations will recover after decades of trapping and poisoning programs.
In distant locations, such as Alaska’s Kenai peninsula, genetic testing showed only four lynx in a generation had managed to arrive from elsewhere to breed.
“The study clearly shows the importance of maintaining dispersal corridors that these wide-ranging carnivores can use,” Buskirk said. “If you assume a new generation of lynx every three or four years, those four animals that arrived will leave their genetic signature. But it doesn’t mean they will make a big impact on the population size in the area.”
For the past three years, government agencies have been releasing captured Canadian lynx in the Colorado Rockies, the southernmost reaches of the wildcat’s historic range.
In 1999, four of the first five lynx released in the San Juan Mountains starved to death. Since then, biologists have been more successful by fattening dozens of the animals for several weeks in captivity before releasing them in the winter when prey is more available.
The federal reintroduction program has been criticized by some Western lawmakers.
In 2000, seven biologists planted samples of lynx fur in two national forests to test whether laboratories could properly identify it. The lawmakers charged that the biologists might have been trying to skew the study in favor of reintroduction and limiting commercial activities in the area. The biologists have since been reassigned or retired.
Earlier this month, the General Accounting Office found that the biologists knew they were breaking the rules but that the bogus samples were weeded out and did not affect the survey results.
