Radio collars carried by gray. wolves on a military base near. St. Cloud tell stories of life-and. death-at the southern limits of

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Radio collars carried by gray wolves on a military base near St. Cloud tell stories of life-and death-at the southern limits of Minnesota's wolf range.

1 Radio collars carried by gray wolves on a military base near St. Cloud tell stories of life-and death-at the southern limits of Minnesota's wolf range. By Gustave Axelson T: (hey sure don't look like wild wolves, I thought. This doesn't look like wolf country either. Before me bustles a crowd of scientists and onlookers. Department of Natural Resources animal survey coordinators Brian Dirks and Julie Dejong are briskly extracting blood samples and outfitting radio collars on two sedated canine forms legs bound and snouts muzzled. Dirks announces that the gray one is an alpha male. * DNR WILDLIFE

DNR WILDLIFE DNR researchers measure teeth and record other observations about a black wolf (also featured on preceding page) in the Camp Rip ley wolf research survey.

3 DNR WILDLIFE DNR researchers measure teeth and record other observations about a black wolf (also featured on preceding page) in the Camp Rip ley wolf research survey. The wolf was sedated by tranquilizer and covered with a blindfold and muzzle to keep him calm should he wake up unexpectedly and to keep researchers safe. The pad underneath the wol/ provides insulation /rom the snow, so his body temperature stays normal during sedation. DNR WILDLIFE He's large and his fur is thick, and his body heaves in deep breaths. The black one is still and scrawny; it looks like a medium-sized German shepherd. They're surrounded by more than 30 spectators: a mix of fidgety teens from a local high school and adults invited by Dirks and Dejong to witness this annual exercise in their wolf research. An invitation to watch wild wolves, even wolves rendered prone and unconscious by tranquilizers, can draw a crowd. I look around at the landscape and see leafless hardwoods; austere oak stands amid snowy, scrubby brushlands on a nippy, bright February day. An olive-green army truck rumbles by on a gravel road. This is not the north woods wilderness where wolves roamed in Sigurd Olson books. It's Camp Ripley, a Minnesota Army National Guard Training Site about 40 miles northwest of St. Cloud and the home of two packs of gray wolves. A decade of wolf research here shows that wolves fare much better within Camp Ripley, even though it's rocked by cannons and conquered by troops in training, than they do farther south, where highways and home developments break up their habitat. Elsewhere along the southern boundary of Minnesota's wolf range, surveys show that 20 MINNESOTA CONSERVATION VOLUNTEER

4 range expansion has stopped for the first time in 30 years. Wolf packs may have stopped their southward push for recolonization (historically, wolves roamed the entire state) for the same two reasons that Camp Ripley wolves die when they venture south: roads and people. Persecution, then protection Wolves showed up at Camp Ripley about 20 years after they were protected as an endangered species and more than a century after they were eradicated from the area. Prior to European settlement, wolves ranged throughout Minnesota, from prairies to forests. In 1849, the government issued a bounty for wolves in a newly established territory called Minnesota; a wolf pelt was worth $3. By 1900, wolves were exterminated from southern and central Minnesota. Minnesota's wolf bounty ended in 1965, when pelts were worth $35 and wolves had been extirpated from all of the 48 lower United States except Minnesota, where about 750 wolves lived in the Boundary Waters. In 1974 Minnesota's wolves were protected under the federal Endangered Species Act. Four years later a wolf recovery plan was proposed by the U.S. Fish and Wildlife Service. The plan set a population goal of 1,400 wolves by the year By 1989 a survey estimated between 1,550 and 1,750 wolves lived in Minnesota. Today, Minnesota has about 3,000 wolves. In 1994 soldiers at Camp Ripley started seeing wolves. The arrival of wolves could have restricted troop training on the base, if the training was shown to inhibit the recovery of an endangered species. In 1996 the Department of Military Affairs for Minnesota began funding DNR research of radio-collared wolves on Camp Ripley to determine if military operations harmed the wolves in any way. Ten years of research has shown that wolves and soldiers accommodate each other just fine on the 53,000-acre military base. Since 1995 Camp Ripley's wolf population has grown from one pack of about six wolves to two packs totaling about 15 wolves. Tracking of radio-collared wolves revealed that a pack often dens inside an artillery range in early spring, when the guns are quiet. Mothers move the pups to a new location in May, before troops commence training in June. Once firing begins on the range, one study showed that radio-collared wolves move toward the explosions of shells about 60 percent of the time perhaps out of curiosity. "They seem like pretty smart animals," says Col. Richard Weaver, camp commander of Camp Ripley. "They stay out of sight. It doesn't seem like we bother them, and they don't bother us. In fact, we're pretty proud to have them here." Expeditionary wolf The DNR is happy to have a fully funded opportunity to study wolves. Military funding of the Camp Ripley wolf surveys continues because the Endangered Species Act compels federal agencies to continually show conservation of endangered species. "It's easier to study wolves here than in the Boundary Waters," says Dirks, lead DNR researcher on the Camp Ripley wolf surveys. An on-base airport is convenient for helicopter flights to monitor radio-collared wolves and capture wolves for new collars. The DNR wolf research at Camp Ripley has yielded other intriguing discoveries. For example, five of the six wolves captured for radio-collar outfitting or replacement last JANUARY-FEBRUARY

5 A wolf is spotted during a helicopter flight by DNR researchers over Camp Ripley. "I like having wolves around here," says Jim May, a local resident. "It means things are still working out in the woods." February had raging cases of Lyme disease, according to blood samples. The sixth wolf's blood showed it had contracted the disease and recovered. "Without treatment, any domestic dog would die from Lyme disease levels that high," says Dirks. "These wolves were healthy and coping with it." Another important finding regarded wolf movements. "It was always thought that Minnesota wolves colonized Wisconsin," says Dirks. "Satellite telemetry allowed us to track two wolves as they traveled from Minnesota to Wisconsin and Michigan." For about seven months, one of those traveling wolves journeyed more than 2,600 miles in a grand loop east to Green Bay and south to Wisconsin Dells before returning home to Camp Ripley. Dirks says that while other research in Canada had documented wolves traveling to follow caribou, this was one of the longest documented movements of an expeditionary wolf. The female wolf's next trip didn't last very long: She was shot and killed soon after leaving the base. Her radio collar was cut off and s stomped into a hole in a swamp. Other radio-collar trackings further dem- onstrate the peril for wolves that venture off the protected confines of Camp Ripley. In winter 2005, a pack of seven wolves four of them collared migrated south beyond the base's boundary. One wolf was shot illegally. One wolf mysteriously disappeared; its collar was never found. Another wolf was found dead in a cornfield. The body was too decomposed to determine how she died. The whereabouts of the remaining three uncollared wolves are unknown. And one other collared wolf a scrawny black wolfreturned to Camp Ripley alone. He joined a new pack that formed to fill the territorial void in the southern half of Camp Ripley left by the dissipated pack. Death beyond the boundary From 1996 to 2006, the DNR outfitted 30 wolves with radio collars at Camp Ripley. Today researchers are monitoring six wolves 22 MINNESOTA CONSERVATION VOLUNTEER

6 with working collars. Eight wolves had collars that stopped working or were retrieved, and they haven't been outfitted with new collars. And 16 are known to have died: one wolf pup starved; five were shot; one was poisoned; four were hit by cars; two died of unknown causes; and three wandered to other parts of the state, were labeled problem wolves, and killed as part of the U.S. Department of Agricultures wolf depredation program. Dirks says he's never received a report of a radio-collared wolf killing livestock near Camp Ripley, despite nearby cattle and turkey farms. Bill Paul, assistant state director of USD A Minnesota Wildlife Services the federal agency that manages wolf/livestock conflicts says there have been few complaints about wolves around Camp Ripley. "There's plenty of deer and beavers here for our wolves to eat," Dirks says. "Of course, some people are shooting wolves and they're not telling me. But I would think I'd hear about it if wolves were taking cattle." While Dirks is concerned about the poaching of this endangered species, he says that deaths in the Camp Ripley wolf study haven't been above the normal mortality rate for wolves in the wild. "The deaths don't appear to have impeded the overall wolf population on Camp Ripley," he says. Of the 16 wolf deaths in the study, 15 deaths occurred off base. The way in which many Camp Ripley wolves were killed several shootings and roadkills may provide a clue to what's happening all across the southern border of Minnesota's wolf range. DNR wolf surveys indicate that the wolf range has stopped growing, at least for now. Minnesota's wolf range depicted in the survey was identical to the survey, Top: /Minnesota's wolf range didn't change between statewide surveys in and Bottom: Recorded locations from a wolfs satellite-tracked collar show a 2,600-mile trek into Wisconsin in the first time in more than 30 years of surveys that the wolf range in Minnesota didn't expand. Minnesota wolves could be content to stay put, given the deer population in wolves' current range is at an all-time high. But DNR wolf biologist John Erb says that JANUARY-FEBRUARY

7 Above: The black wolf of the Camp Ripley study sports a new radio collar after waking from sedation. Opposite page: Even while recovering from capture, two Camp Ripley wolves display typical pack behavior. The lesser wolf (standing) shows submissiveness to the alpha male by keeping his head and tail down. doesn't fully explain the halt in wolf range expansion. Most suitable wolf habitat within Minnesota's current wolf range is already occupied, and the competition for space is intense. The survey showed that individual pack territories shrank. So why, Erb asks, don't wolves expand farther south of the current range boundary, where they would have no other wolves to compete with and plenty more deer to eat? The answer may be evident in a road density map of Minnesota. The current wolf range runs along a meandering line from northwestern Minnesota to midway between Duluth and the Twin Cities southwest of that line, the number of roads per county increases significantly. "Roads kill wolves in two ways. They bring cars, which hit wolves; and they bring people, which increases the chances of consistent disturbance or illegal shooting," says Erb. "I believe more roads, more people, and more disturbance in an increasingly fragmented landscape is keeping wolves within their current range for now, although they could certainly expand in the future." 24 MINNESOTA CONSERVATION VOLUNTEER

8 Erb says that more roads and more people are also exerting more pressure on wolves within their existing range. "Due to bustling development in many areas of the north woods, the differences between north and south aren't what they used to be," he says. "If this continues, we run the risk of creating more isolated Camp Ripleys smaller islands [of wolf habitat] surrounded by expanding areas that are more hostile to wolves. "We're at a crossroads for wolves in Minnesota," Erb says. "The more tolerant wolves are of people, the better off they'll be, since more people are moving into wolf country. But the more they adapt to people, the greater the chance they'll be bold and more visible, which could lead to more potential conflicts and more killing. Mutual tolerance between humans and wolves is key to wolves' future." Reawakening The crowd around the two sedated wolves has departed. Dirks, Dejong, and the onlookers went north to capture more wolves. I volunteered to stay behind with a St. Cloud State University wildlife biology intern. The two of us are watching to be sure the wolves run off after they wake up. They've been sleeping for two hours, wrapped in blankets inside dog kennels with open doors. If they recover in a closed kennel, they might tear the kennel apart before researchers return to set them free. The black one awakens first and disappears into the woods. Minutes later, the gray one drags himself a few feet out of the kennel still groggy from the tranquilizer. I approach tentatively for a closer look, and his bumt-yellow eyes lock into mine. His stare sears any feelings of comfort I had about his immobilization. He is, unmistakably, a wild wolf. Behind me, the black wolf reappears. He has doubled back, maybe to check on his pack's leader. "Wolves are incredibly loyal," Julie Dejong, a DNR veteran of these Camp Ripley wolf surveys, told me later. She recalled another time, in 2004, when she watched two sedated wolves recover together. "A non-alpha male woke up first and had the opportunity to kill the alpha male. It was the perfect opportunity to take over the pack But instead the nonalpha wolf stayed close by. The non-alpha continued his submissive behavior, with his head down and his tail down, and they eventually ran off together." Loyalty probably served the scrawny black wolf well when he integrated into a new pack. As he paces among the trees, I wonder if he was able to communicate to other wolves about the deaths he saw when his old pack ventured away from camp, south of today's wolf range. I wonder if elsewhere along that boundary, there are other lone wolves returning north, telling their new packs a similar story. Gustave Axelson is managing editor of Minnesota Conservation Volunteer. JANUARY-FEBRUARY

Threatened & Endangered Species Tour Post Visit Activity Packet

Threatened & Endangered Species Tour Post Visit Activity Packet We hope that you enjoyed your visit to the Mill Mountain Zoo. To enhance you and your students experience, we have put together a little