Wolves Take Back the Wild
One chilly early morning in late October of 1998, as the sun rose over Yellowstone National Park's Lamar Valley, biologist Robin Silverstein and the rest of his team of field technicians clambered up a rocky hillside and set up shop for a day of work. After assembling their telescope, booting up their handheld Hewlett Packard computer and unfolding their Crazy Creek camp chairs, the members of the Yellowstone Ecological Studies (YES) group scanned the verdant valley that has been called the"little Serengeti of North America" because of its abundant wildlife population.
Elk, bison, and other big game range the meadow on the valley floor as they have for decades, but now things are changing in Yellowstone. After a long absence due to man's near eradication of the species, grey wolves (Canis lupus) are making their presence felt. A number of these wolves, originally captured in Canada, were reintroduced to the Yellowstone area in 1995, in perhaps the most high-profile and controversial program of its kind. The National Park Service estimates that around 120 wolves, including pups, inhabit the Yellowstone ecosystem.
But this is not the only wolf reintroduction program taking place in the United States. Mexican wolves have been loosed in Arizona, and Red wolves have been reintroduced in the Great Smoky Mountain National Park and the Alligator River National Wildlife Refuge in North Carolina. Still, the grey wolves of Yellowstone have attracted the most attention as of late, both from the public and from researchers like Silverstein.
That crisp October morning on the hillside, Silverstein spotted a large bull elk grazing and bugling, as wolves of the Druid Peak pack circled, one occasionally jumping in to nip at the elk's heels. Seemingly unconcerned, the elk continued feeding, stopping to charge at the interlopers now and then. Eventually, the wolves moved on, leaving the elk in peace. Researchers say elk that stand their ground have a much better chance of surviving than those that run. Standoffs like this have become increasingly common since the wolves began to retake the territory where their species once was populous, and elk have been forced to become more vigilant.
Like the elk, other species within the park have been dramatically affected by the growing number of wolves. The animals Silverstein studies, the coyotes, have had their population cut by more than half since the wolf reintroduction. This year, one coyote pack had ten pups, four of which were killed by wolves. In the area where 80 coyotes once lived, there are now only 36, and the coyote packs have adjusted their home territories to account for the wolves' home turf, according to Silverstein. Still, there are big benefits for the ecosystem as a whole. Since the wolves kill elk (they kill one elk every one to five days, on average), grizzly bears, foxes, bald eagles, and golden eagles can scavenge the elk meat that the wolves leave behind. The proliferation of available elk meat, and the reduction in the coyote population, has also meant that there are significantly more rodents for other predators to feed upon.
The story of efforts to reintroduce Red wolves (Canis rufus) to the Great Smoky Mountains National Park doesn't end quite as happly, although the US Fish and Wildlife Service's (FWS) red wolf coordinator, Gary Henry, says the agency learned a lot from the failure. During the eight years the program was in existence, 28 pups born in the wild died; the only two that survived were removed from the park at six months of age.
"It's hard to determine exactly what killed them, because you rarely get carcasses," said Henry."What apparently is happening is that [the adults] are not getting enough nutrition back to the pups."
That lack of nutrition, due to a lack of sufficient prey species, may have made the pups, and the adults, more susceptible to disease and predation, said Henry. A lack of food within the park's boundaries may have caused the adults' tendancy to wander outside the reintroduction area. Still, Henry and his colleagues aren't giving up.
This experience, and a successful 12-year-old reintroduction program at Alligator River National Wildlife Refuge in North Carolina, have taught biologists about the habits and preferences of the red wolf. Scientists previously knew very little about the animals' natural behavior, because of their scarcity in the wild. From an initial population of 14 wolves, captured from Texas and Louisiana, the FWS management programs have resulted in a population of over 300 animals. Some of these (80) live in the Alligator River NWR, and the rest reside on islands off the coasts of Florida and South Carolina, a somewhat wild atmosphere that biologists hope will be a stepping stone to a true wilderness existence.
Now FWS scientists are just looking for somewhere to reintroduce the creatures. For the next couple of years, researchers will be plugging data into a computer, using it to compare the wolves' likes and dislikes with the characteristics of public lands in the animal's historic range. Eventually, they hope to have 220 red wolves living in the wild, with a total population of 500.
Meanwhile, in the American southwest, another team of FWS scientists are beginning to reintroduce Mexican gray wolves (Canis lupus baileyi) in Arizona and New Mexico. This reddish-brown, buff, black, and gray creature once ranged from central Mexico to western Texas, southern New Mexico and central Arizona, but by the mid-1900's it was virtually eliminated from the wild in the United States. The last time a wild Mexican wolf was seen in the U.S. was in 1970.
In March of 1998, the FWS released three packs of Mexican wolves into the Apache National Forest in eastern Arizona. A captive breeding program in New Mexico, which was started with animals gathered from zoos and other conservation facilities in the U.S. and Mexico, provided the 11 wolves that were reintroduced.
Although biologists were thrilled when the first pup born in the wild was spotted (it was the first pup born in the wild in about 50 years), the program suffered a big setback when the pup's mother was killed in August, apparently by a mountain lion. Since that time, researchers have lost track of the pup and presume that it is dead. Of the original 11 wolves released in March, only four were still living in the wild by late October. Three are in captivity after being recaptured, three have died, and one is missing. Biologists planned to continue releasing more wolves into the areaa few more will be reintroduced each year.
It may be tempting to compare these three reintroduction programs and conclude that the one in Yellowstone has been the best managed. In fact, each program began with its own unique challenges, and it would be unfair to look only at the outcomes. The Yellowstone effort is operating at a significant advantage, because the wolves that were reintroduced there were culled from packs living in the wild in Canada. Both the Mexican wolf and the Red wolf programs have a more difficult mission, because they are beginning with animals that have been wholly reared in captive or near-captive situations. This distinction "makes all of the difference in the world," according to Yellowstone Wolf Project leader Dr. Doug Smith. Still, even after failures like the one in Great Smoky Mountain National Park, biologists are hopeful. "We were flying by the seat of our pants," the FWS' Gary Henry said of the early years of red wolf reintroduction. "Nobody knew very much about red wolves." But now the scientists are learning, and Henry says they have every reason to believe that they'll be successful.
Details mentioned in this article were accurate at the time of publication