On a downtown Boulder street-corner, a cluster of protesters is prompting some rubber-necking from passing motorists. "The Lynx are the Division of Wildlife's Sacrificial Lambs," reads one hand-lettered sign, held aloft by a local animal-lover. "Bad Idea; Bad Plan; Dead Lynx," proclaims another.
The plan that disturbs these protesters is one to reintroduce lynxes to the mountains of central Colorado. From the start, the idea bothered a diverse group of opponents - from conservation biologists who doubted there was enough food for the animals to cattle ranchers who saw no need to add more predators to the area. Five cats were released into the wilds last month, but now that two of them have died, the debate is taking on a new urgency.
At the heart of the dispute is a troublesome question: Is it ethical to sacrifice the lives of individual animals for the larger goal of reviving a species?
To state wildlife experts, the loss of two lynxes transplanted from Canada is disheartening, but not unexpected. "We knew going in that we could expect a 50 percent loss or more," says Gene Byrne, a Colorado Division of Wildlife biologist. "We still believe we'll be successful in recovering these animals."
To protesters, Colorado's $1.4 million program to let 100 lynxes loose in the San Juan Mountains should be halted immediately.
"How many more lynx have to die?" says Marta Turnbull. "I like the idea of reintroduction of species. But it's more complex than people think."
Even among reintroduction enthusiasts, few would disagree with that assessment: Complex only begins to tell the story. Indeed, whether any reintroduction effort can succeed long term - and at what cost - remains an unknown.
For one thing, when it comes to species reintroduction, one observer's failure is another's success. An effort to restore Mexican wolves to New Mexico and Arizona was halted last year, for example, when 4 of 11 wolves released had been shot and a fifth was missing. But the wolves otherwise seemed to be adapting well. In fact, federal wildlife managers plan to resume the program in the spring.
Proponents also cite apparent successes: American bald eagles, red wolves in North Carolina, and to some degree, California condors. A controversial program to restore gray wolves to Yellowstone National Park also looks promising: About 250 wolves now breed in the area.
But to many, reintroductions raise important questions about human stewardship of the animal kingdom. Critics say it's wrong to expect nature to conform to human expectations.
"A lot of people think it's very cool and wonderful to have lynx out there," says Marc Bekoff, an animal behavior researcher and biology professor at the University of Colorado here. "I do, too. But it's not fair to put them out there when they're just going to die."
He is among those who believe there isn't enough prey base for the tuft-eared wild cats, which eat snowshoe hares almost exclusively. "I'm not against reintroductions," Mr. Bekoff continues. "But when you're dealing with carnivores like wolves and lynx... those efforts mostly have failed."
For supporters, however, the sacrifice can be worth it because ripple effects from species reintroductions benefit entire ecosystems. "Ecosystems need all their components," says Nina Fascione of Defenders of Wildlife in Washington. "It's about restoring what we should have gotten from our forefathers, and managing it for future generations."
From that standpoint, she says, the loss of some animals is justifiable for the greater good of a successful species restoration. "Our position is very firm that it's a tragedy when an animal gets killed. But the overall good of conservation of the species is the most important thing."
After the early losses, Colorado wildlife officials will make some adjustments. The lynxes - which are imported from the Yukon - will stay in holding pens longer before release, so they can better adjust to their surroundings, says Mr. Byrne. They'll also be fattened up more before they're freed.
Officials hope simple modifications will make the difference. But "there's no cookbook on this," he says. "We're only the second place ... to do a lynx reintroduction." A lynx program in the Adirondack Mountains of New York failed after most of the animals were hit by cars.
A rough start shouldn't automatically be seen as a harbinger of failure, says Benjamin Beck at the National Zoological Park at Smithsonian Institution. Dr. Beck, who has helped with reintroduction of golden lion tamarins to Brazil since 1983, says most of these small monkeys died within the first two years of the reintroduction program. But afterward, the survival rate began to climb. Today, after spending 15 years and about $5 million, the population of tamarins has tripled to 900.
Beck says humans have an obligation to conserve nature's biodiversity. "Unequivocally, it's a cultural obligation," he says. Yet some efforts will fail, and even in the best reintroductions, some animals will die, he notes.
Ultimately, decisions about species restoration in the US may be made by politicians, not biologists. An Idaho law prohibits state wildlife officials from helping in federal efforts to reintroduce endangered species. And in Colorado, the Legislature is pushing forward a bill that gives lawmakers - not state wildlife officials - final say on any state-sponsored wildlife reintroductions.