A study of the skulls of Ghost Ranch wolves by Michael Bogen and Patricia Melhop in 1980 concluded that they “show tendencies toward dogs, but whether these result from dog genes or the effects of captivity is unknown.” The single doglike characteristic the researchers found was one wolf’s shorter muzzle. But shortened muzzles may merely be features of domestication, not of hybridization. Bone is trained by muscle, and muscle by the exigencies of life. Just as an old man’s jaw may recede if he loses his teeth, or an athlete adds bone mass by lifting weights, a pup raised on soft foods in captivity might have a shorter muzzle because it develops less muscle—and therefore less bone to anchor the muscle—than its wild relatives. Even wild–born lion cubs taken into captivity show shorter, broader skulls than wild lions. Similar changes have been observed in purebred wolves in zoos. A 1941 study concluded that “skulls of wolves reared in captivity are shorter, broader and higher than those of wild wolves” and “nearer to those of domestic dogs.”
Even if there were dog genes in the Ghost Ranch wolves, Ames argued that historical evidence suggested there had been dog genes in the wild population for a long time. Gish had reported that federal trappers frequently trapped hybrids or saw wild wolves running with feral dogs. “If dog genes did indeed exist in the baileyi populations in the past,” Ames asked, “what objections can there be to releasing baileyi individuals today that might be similarly tainted? How can we prove, for that matter, that dog genes didn’t exist in the wild population before?”
Despite Ames’ defense, the Ghost Ranch wolves were increasingly viewed as tainted. In 1977, the U.S. Fish and Wildlife Service sent trapper Roy McBride to capture wolves in Mexico. He came back with three males, and a female that proved to be pregnant. They were placed in the Arizona-Sonora Desert Museum, where the female gave birth. Pups from that and successive litters have been shipped to other breeding facilities, such as the Wild Canid Survival and Research Center in Eureka, Missouri, and the Rio Grande Zoo in Albuquerque. That provided a rival line of breeding stock to the Ghost Ranch wolves, with which McBride wolves have never been crossed. Since then, the McBride line has produced more than 170 pups, and there are descendants in fifteen facilities, including the Phoenix Zoo and the Chapultepec Zoo in Mexico City. By 1993, there were more than ninety wolves in the “certified” McBride or Arizona-Sonora Desert Museum line.
Once the McBride wolves were breeding in captivity, those who had them were even more critical of the Ghost Ranch line, and the Arizona-Sonora Desert Museum stopped breeding Ghost Ranch-line wolves. To avoid charges that all captive-bred wolves were tainted, recalls Ames, “the U.S. Fish and Wildlife Service wanted to kill all the other breeding stocks.” The service recommended at least neutering all the Ghost Ranch wolves. Everywhere, the line was devalued, disparaged, or destroyed. The Living Desert State Park, in Carlsbad, New Mexico, euthanized five young males in 1979. When the Arizona-Sonora Desert Museum got down to the last of the Ghost Ranch—derived wolves, a female that had failed to breed, they kept her in an indoor facility with a sign on the door saying “The Thing.” The Ghost Ranch asked to have the wolf, but the Arizona-Sonora Desert Museum staff decided to euthanize her.
This new line of certified wolves was not without its own problems. One of the males never bred in captivity, so the founding stock of the McBride line was four individuals. With only four founders, the McBride wolves risked inbreeding depression, or loss of genetic resources to the point where they were less likely to survive. There was an enormous desire to add to the gene pool by adding wolves from other lines, but the additional possible sources all posed problems. The Ghost Ranch line was regarded as tainted. There was another lineage of Mexican wolves, at the San Juan de Aragon Zoo in Mexico, the founders of which came from the Chapultepec Zoo, but the lineage cannot be traced back to a wild ancestor. And it was rumored that some of the Aragon wolves had been bred to a dog by a keeper who wasn’t thinking about returning them to the wild. There was much discussion of whether to try to capture more wolves for the captive-breeding program. Says Ames, “Some people said, ‘No, no, no, don’t take any more out of the wild. Save them in the wild.’ ”
For Ames, it was a difficult situation. She couldn’t become an advocate of including the Ghost Ranch wolves in the breeding stock, “because I saw the argument that Mama wants her child on the team. I had to play my personal involvement with them down quite a bit. I’d get criticism from the Fish and Wildlife Service. They wouldn’t say anything directly about me, but they’d say, ‘There are all those people raising wolves in their backyards, thinking they’re doing a favor for the species, and they’re not doing anything for the species.’ ”
Several studies suggested that the Ghost Ranch line ought to be brought into the breeding stock. Work by John Patton, of LGL Ecological Genetics of Byron, Texas, found the same distinctive Mexican wolf-DNA markers in Ghost Ranch wolves and in the certified line. Ulysses Seal, of the Captive Breeding Specialist Group at the Minnesota Zoological Gardens, recommended that the Ghost Ranch population be included in the breeding population. “Most of us were convinced that these were pure Mexican wolves,” says Ames, “but because there was that question of possible dog blood in it, it became politically unwise to add it.
“I hoped at first my wolves would go back into the wild. I thought I was helping to save the Mexican wolf. I kept raising them in such a condition that, if they were ever certified, they wouldn’t have been conditioned to people.” But it became increasingly clear that these wolves were not going to be approved for release.
“About 1980, when I could see the way things were likely to go politically, and that there was not going to be a place for wolves of this lineage to go, I decided I would have to stop breeding them.” She began to separate the females in breeding season. No pups gladdened her summer days. One by one, the wolves aged and died, and she would carry them out of the pens in deep sadness, and bury them. By 1987, she was down to one last wolf. She had retired from the department, and she was about to remarry, sell her place in New Mexico, and move to another part of the country. There was no breeding program to accept the animal. She could not bring herself to exile it to solitary life in a cage in a zoo. She decided she would have to euthanize the last wolf.
It took her a month actually to do it. She went out one morning to “get it over with. I had the one wolf alone in one of the large enclosures. All through the years I kept them, I found it difficult to provide the wolves with medication, because they’re suspicious of things. Vets said, ‘You just sprinkle this medication on their food,’ but it doesn’t work that way. All through the years I had them, I bought immense quantities of frankfurters. Every day, I went out and broke frankfurters into pieces and tossed them to the wolves.” The wolves would catch them in midair and bolt them down to keep other wolves from getting them. When she needed to immobilize a wolf, she would put tranquilizer pills in the frankfurters. On this day, she tossed the last wolf a bit of frankfurter and tranquilized it. “I went out and injected a killing drug. It took seconds.
“It was hard to do,” she says. She had loved the wolves, and there were few people to share her grief. “You had to be careful about who you told about it, because they’d say, ‘She doesn’t really care about wolves, she killed her wolf.’ ”
It wasn’t the end of the Ghost Ranch line, however. In 1992, there were sixteen survivors of the lineage, some at Ghost Ranch, others at the Navaho Nation Zoo on the Navaho Indian Reservation, the Hillcrest Zoo in Clovis, New Mexico, and two private facilities in Colorado. But they were still shunned by the Mexican Wolf Recovery Team.
Ames moved with her new husband to Colville, Washington, but she still has cause to be intensely interested in wolves. Wolves are beginning to drift down from Canada into the Selkirk and Cascade mountains. “People come and talk to the wolf lady and tell her about the wolf they just saw,” she says. Many of the sightings she thinks are coyotes or dogs, many she supposes are hybrids. Meanwhile, local ranchers circ
ulate rumors that the U.S. Fish and Wildlife Service has secretly released wolves. “They say, ‘We heard some howling the other night.’ ”
Mistrust now hovers over the McBride line of wolves. With only four founders, its detractors say the wolves are so inbred that they ought not to be released. In Dennis Parker’s view, “One female and two males is insufficient to sustain a viable population.” If such criticisms are valid, we ought to be able to see evidence in the McBride line of wolves that has been bred in the Rio Grande Zoo in Albuquerque, New Mexico.
At the zoo, the Mexican wolves are enclosed in a lodgepole-pine stockade that circles a half-acre habitat. The exhibit is shaded by large cottonwoods and small junipers. It is leafy and green with grass and low shrubs. In the center, under the shade of the cottonwoods, is a mound of worn red earth where two wolves sprawl. They are unconcerned at the cries of peacocks, the roar of lions, or the squawk of parrots. When the first human visitor of the day arrives, however, the female is up immediately, glowering, her tail pressed low between her legs. Then she turns and takes off at a hurried, loose-limbed trot. Moving around the perimeter of the enclosure, head low, lips parted, glancing up apprehensively at the visitor, she slinks, trying to outrun her apprehension. And one can see in the cold yellow of that over-the-shoulder glance how fear must have crossed and recrossed this exchange of gazes over the centuries. With each circuit, she uses a well-worn trail in the underbrush. She pads on paths abraded by this ragged desire to be somewhere else. It takes her half an hour to settle down. Always when she stops at the mound, she turns and stares at the cage door, where a keeper might appear. If a human enters this enclosure, the wolves move as far away from the person as possible. “If we don’t let ’em get away from us, they’ll jump on the walls,” says Kent Newton, Rio Grande Zoo’s curator of mammals. He sees the wolf’s nervousness as evidence of its wildness.
Newton stands outside the enclosure and looks at the wolves. His face is young, but his hair shows hints of gray. His neatly trimmed mustache and polished cowboy boots suggest that he is divided between city and country. As guardian of these wolves, he must see himself as both herdsman and liberator. At times, he must wonder what these walls do to the wolves and to his own wild nature.
For their part, the zoo visitors spend little time in front of the wolves: the maximum stay is about thirty seconds. People look into the trees and bushes to find the shape and register in their brains the word “wolf,” then move on to the polar bears and lions. To see a wolf in a zoo is to see a picture of a wolf. It’s not doing anything. People howl at it or shout “Lobo!,” but it doesn’t lift its head, doesn’t even crack open an eye. The wolf has heard all this a hundred times a day for years, and is bored by it. And people aren’t entranced by their own reflected boresomeness. The wolves are too available, but not sufficiently dramatic. “I’d rather see them in the wild,” one woman says to another.
Of course, there are none to be seen in the wild. The pair in front of them is the most accessible pair of Mexican wolves in the world. They have borne two litters in the past two years. Some of last year’s pups are in a separate facility here, and others have been shipped to other breeding centers. The six pups currently in the den come up twice a day to be fed.
The Rio Grande Zoo has produced forty-four McBride-line pups, and all of them so far have survived. It was not a seamless tale of success, however. At first, the wolves were all kept in adjoining pens, and dominance struggles through the fences seemed to keep them from breeding. Only when they were put into secluded pens did they begin to breed. Since then, much care has had to go into the pairings. Wolves thrown together for the purpose of breeding may not bond, may not like each other, may not know the right gestures to unlock the mysteries of sexual union. They may be neurotic from living inside fences and being stared at all their lives, or they may be distracted or silly, aloof or bored.
Normally, zoos like to speed up the breeding of such creatures by tinkering with the technology of reproduction. There is extra interest in speeding up the reproduction of Mexican wolves because the recovery team has decided that until there are one hundred animals in the breeding population, none will be released into the wild. Also, the larger the breeding population, the smaller the likelihood of inbreeding depression. But there are limits to what can be done. Capturing females to inseminate them may cause such stress that they cannot conceive. Accustoming them to handling to counteract the stress may eliminate traits that are necessary for survival in the wild. Says Newton, “Since these animals are potentially release animals, our philosophy is hands off.”
Parker believes captivity has already altered these animals. “Look at the old-type animals,” he says. “They’re higher-shouldered in the front, they’re longer-legged, they have a broader head and broader snout.” The captives, he says, “have bat ears that resemble a German shepherd. They’re actually creating an animal in captivity. When you have captured animals, you are fostering a whole new set of parameters.” He suggests that raising these animals in cold-climate breeding centers like the Detroit Zoo or the Point Defiance Zoo in Tacoma, Washington, may alter them in unknown ways.
Newton thinks little of Parker’s charges. To his eye, these wolves look authentic. He points to a study of the wolves’ DNA conducted by Dr. Steven Fain of the U.S. Fish and Wildlife Service’s National Fish and Wildlife Forensics Laboratory, which indicates that the present McBride-line wolves have 90 percent of the genes of their founders. He says, “We’ve had Dr. Robert Wayne and Dr. John Patton study the genetics of the captive wolves. They reached the conclusion that the Mexican-wolf population is as heterozygous [genetically diverse] as the northern gray-wolf population.”
Newton adds that the wolves in front of us are behaviorally every bit Mexican wolves. “The animals pair-bond, they copulate, they dig natural dens, they birth their offspring in the dens, they nurse, they regurgitate food for the pups, with aunting behavior by the other adults. There is a peck order that is established as the pups are growing up. At one time we had eleven animals in here, adults and two litters, with little aggression at all. So, in general, we haven’t seen any loss of genetic ability to maintain a cohesive unit. When the female goes in the den to whelp, the male stays out in a high place as a sentinel. The adult male will even carry food to her when she is first having the pups. Security guards at night hear them howl. The female vocalizes to the pups. She calls them out of the den. She will make a whining noise to call them back into the den when she feels security is compromised. They have the so-called edginess or perceptive ability which has been lost in domestic animals. We see all of the classic behavior text mechanisms that you would read about in a book. It’s all there. We haven’t seen any indication of inbreeding depression through testing or behavior.”
Dr. Steven Fain is perhaps a little less sanguine than Newton. “We have genetic variation,” he says. “We don’t have much to work with. This is an example of a very, very genetically depauperate species.” He describes what is happening. Of twelve specific DNA sequences identified in two of the founder wolves, only six were passed to the next generation. In the next pairing, he found seven variations, but one offspring only inherited one of them, and another inherited five. “The variation is still there,” he says, “it’s just averaged over a larger number of individuals.” Careful breeding may conserve enough of the genes for the wolves to survive.
When Fain looked at the same DNA segments in the Ghost Ranch and Aragón Zoo wolves, he found that the Ghost Ranch line had more variability than the McBride wolves. He concluded that bringing the Ghost Ranch and Aragón lines into the breeding program could double the genetic variability of the Mexican wolf.
Whether or not the various gene lines are brought together, the very existence of these wolves seems to demand a future release into the wild. For, in the end, a wolf in a zoo is not a wolf. It is the interaction of genes and environment that makes a species, and the whole complex interplay of thousands of such processes that
makes an ecosystem. If we lock wolves up in zoos, we stop the interactions. We change their evolution.
So Newton proceeds all along as if these wolves are aimed at eventual release. He wants them to dig dens, to stay shy of humans, to keep their social habits. The wolves aren’t named, because, “when you give them a name, you want to talk to them. The first thing humans want to do is relate to an animal. I don’t want any relating to these animals at all—no talking, no play. In the long run, that will benefit reintroduction if that occurs. My philosophy is to give them numbers. That keeps the human psyche away from them.”
But where are we going to put the wolf? Newton can’t do much about this question here at the zoo, and it is a question that much troubles him. He looks back at the stockade. The female wolf is up again, running the barrier path, looking apprehensively over her shoulder.
The Mexican wolf’s prospects south of the international border are at best dim. “There is very little hope for the Mexican wolf,” sighs Julio Carrera of Antonio Narro University in Saltillo, Mexico. Carrera is a round-faced man with dark, inquisitive eyes and a neatly trimmed white beard. He has a look of pained resignation about him. “My whole life I am interested in wolves,” he says. He has tried to be the Mexican government’s point man on the subject. But the government hasn’t embraced Carrera or his efforts, so he has had to seek private backing for his project.
He has been looking for wolves in Mexico. Canis lupus baileyi once ranged south through Durango and Zacatecas, almost as far as Mexico City. In 1977, the U.S. Fish and Wildlife Service arranged for McBride to go into Mexico to ascertain the status of the Mexican wolf in the wild. He talked to cattle buyers, bankers, and other people who would be likely to hear of wolf predation; he looked at the habitat and talked to ranchers. In his estimate, there were only fifty to a hundred wolves left. Today, Mexican wolves may survive in Chihuahua, Sonora, Durango, and Zacatecas. There were reports in 1991 of three wolves seen traveling along the Chihuahua-Sonora border; American biologist Charles Jonkel says he saw wolf tracks in that area at that time. In 1988, there was a report of a wolf killing cattle on a ranch in Sierra de las Tunas. A forester in the Sierra del Promontorio said he heard howls in 1991. And Carrera spoke with a Mexican trapper who claimed to have seen a wolf drinking from a watering trough near El Salado in Zacatecas.
The Company of Wolves Page 26
