'Nobody gives a damn about the prairie dog'

  • Etching of prairie dogs

    Evan Cantor
 

The dirt two-track rises quickly from the river to a ridge of pines. After a few miles the track veers out onto the sagebrush flats of this high desert plain in Montana, and there, on a patch of ground where grass and sage thin out, I spot what I have come looking for: small mounds of dirt and the dark holes. My presence has been noted. As soon as I cut the motor, the sudden silence is punctuated by a few scattered alarm calls, one of nine distinct barks that inspired early explorers to call them dogs. But I can't spot any.

There's a good chance not many prairie dogs live here now. In small towns such as Zortman, Harlem and Malta, shooting the rodents for fun has become sport and even a boost to local economies.

But prairie dogs face bigger threats than a few guys with guns. Poison is much more effective, and conversion of prairie to farmland has run them out of many a neighborhood.

There's also sylvatic plague. Last summer the flea-spread disease killed 70 percent of the prairie dogs in one county in north-central Montana. That will sound like great news to all the people who think prairie dogs are good for nothing except turning grasslands into dust. But it's a bum rap - one that probably began in 1924, when researchers W.P. Taylor and J.V.G. Loftfield libeled the animal by calling it "one of the most injurious rodents of the Southwest and plains regions' because it removed "vegetation in its entirety from the vicinity of its home."

That report, printed in the U.S. Agriculture Bulletin, fueled a wave of eradication programs that poisoned 20 million acres of prairie dog towns. Add to that the rodents' vulnerability to sylvatic plague, and 99 percent of the historic population, estimated at 5 billion, was gone. Their original habitat is thought to have been 98 million acres - an area larger than Montana. A single prairie dog town in Texas measured 250 miles long and 100 miles wide.

Small animals, but operating on an immense scale. So perhaps it's not surprising to find them ecologically linked to something several thousand times bigger: the bison. The prairie dogs used the trails bison carved into the prairie to spread to new sites. When the bison were eliminated, the prairie dogs found it hard to migrate, and their numbers diminished.

The prairie dogs rebounded momentarily when the homesteaders arrived; cattle and roads provided the trail-making service the bison had once provided. But the homesteaders and ranchers didn't understand that prairie dogs were giving as well as receiving by actually helping the range. The first hint of this had come from early naturalists, who noted that bison grazed off the sparse vegetation in prairie dog towns before moving on to what looked like better forage outside the towns.

Craig Knowles, a biologist in Boulder, Mont., who has studied the prairie dogs for the U.S. Forest Service and Fish and Wildlife Service, finally discovered what the bison had known:

"Even though prairie dog towns appear to be desolate, they are full of plant life. The animal's digging activity disturbs the soil, (and) weedy plants take over, much like in a cultivated field. When closely cropped, these plants become higher in protein and nitrogen content and are sought out by cattle, bison, antelope and elk."

Knowles says that "all the scientific information shows prairie dogs don't compete during the summertime with cattle. In winter, though, when the plants are dormant, cattle will not graze in prairie dog towns." Knowles says it takes about 380 adult prairie dogs to consume as much vegetation as one cow and calf.

Overall, things seem to balance out, according to another study in Oklahoma. There, a control group of cows grazing on a prairie dog town had the same weight gain as cows grazing on taller grasses nearby, even though the cows feeding on the taller vegetation consumed more grass.

Dog watcher

Knowles became interested in the dogs while studying deer and elk on the Charles M. Russell Wildlife Refuge in north-central Montana. He got so interested, the Fish and Wildlife Service funded his doctoral thesis on the critter.

For three years he almost literally lived with the animals, even adopting a prairie dog pup he named Elsie, who dug her burrows outside the door of his field quarters. "They make great pets," he says, but you have to get to them young: "When the pups first come out of the dark burrow they are very docile and they tame down fast. But not the older ones."

Prairie dogs are active during the day, but only if the sun is out. Socially, they organize themselves into coteries, with one male protecting a one-acre plot for four to five females, each with its own five-pup (on average) litter.

The towns become argumentative in the spring, when the new litters are born and the yearlings from the last year's litters attempt to take over. Those who lose - whether young or old - hit the road, following any beaten trail available until they come to a grazed area where they can attempt to create a new town.

At least psychologically, prairie dogs seem to have some lemming in them. "Some prairie dogs on the CMR refuge will walk down a road that ends at a boat ramp on the Fort Peck Reservoir and from there they start to swim," Knowles says. "Since they aren't great swimmers they usually drown. But they never turn back."

Prairie dogs don't seem to hibernate. Knowles has seen marked prairie dogs pop out of their burrows at two-week intervals during the winter. "They just sit on their mounds, then go back down." What do they do down there all winter? Knowles guesses: "They probably just sleep," living off body fat since they don't store food.

An unpopular rodent

No matter how interesting prairie dogs may be, and no matter how helpful they may be to vegetation, most ranchers see them as pure nuisance.

"All they do is destroy the range," says Jim Petersen, a spokesman for the Montana Stockgrowers Association. "They eat the grass around their holes right down to the ground. It's pretty easy to spot."

Some ranchers accuse the rodent of another crime: Their burrows can break the legs of cattle. Petersen, however, writes this off as "pretty far-fetched."

The prairie dog's reputation won't be boosted any by last summer's death of a 16-year-old Colorado girl from bubonic plague, which is spread by fleas carried on rodents and rabbits. It's not the first; since 1957, about 40 Coloradans have contracted the disease. It's definitely a problem, but mass eradication of colonies won't help: the fleas will simply fly off in search of new hosts.

If eradication is proposed, few will leap to defend the animals. "Nobody," points out South Dakota wildlife consultant Jon Sharp, "gives a damn about the prairie dog."


Why? Perhaps because the prairie dog not only lacks charisma - it's anti-charismatic, like its cousin, the rat. Another drawback is the harshness of its home landscape: open sagebrush grasslands that leave humans feeling tiny and vulnerable. Settlers traveling the Oregon Trail passed through the prairie dog's homeland as quickly as possible; motorists on the Interstate do the same.

That's too bad, because the high desert plain, whether in Montana or New Mexico, is as beautiful and intriguing as any mountaintop, desert canyon or coastal bay. Never truly flat, the land wrinkles with hidden washes and draws, swales and arroyos - especially near rivers or creeks.

Walking is the best way I know to see the country. The vegetation can change from grassland to sagebrush and rubber rabbitbrush to dustbowl badland within the space of a half day. And there's always that lone stunted cottonwood tree seemingly miles away on the horizon, but only a half mile in reality, marking an underground spring or seep.

I never find such a walk dull. Animals and birds burst from cover, keeping my adrenaline churning. Jackrabbit, burrowing owl, bull snake, curlew, sandhill crane, fox, mountain plover, bobcat, badger, kangaroo rat and rattlesnake all live in the West's sage flats. Many of them - the swift fox, black-footed ferret, ferruginous hawk and plover - depend on prairie dogs for survival. Those little pests, it turns out, are carrying a heavy burden on their uncharismatic backs - an entire ecosystem.

Predator as savior

The black-footed ferret is the rodent's most famous dependent. Not only does the ferret escape the weather and its predators in prairie dog burrows - it also eats its hosts. The destruction of prairie dog towns hit the ferrets hard and everyone thought they had been driven extinct. Then, in 1981, a surviving colony was discovered in a small prairie dog town in Meeteetse, Wyo.

Ferrets were bred in captivity, trained to hunt and to breed, and in 1994 relocated to a prairie dog town on Montana's Charles M. Russell Wildlife Refuge and to another site in the Badlands National Park in South Dakota. Despite lots of money and lots of effort, the ferret's future is dim, some biologists say, because so much of its surviving habitat is so fragmented.

The loss of prairie dog habitat has also hurt the burrowing owl. Once common across the West, the owl has been considered a species of special concern by the National Audubon Society for 10 years. The owl doesn't eat many prairie dogs, but it uses the mounds as a sort of lookout tower to spot insects, mice, snakes and lizards. While the parents are peering around in search of prey, the owlets are sheltered in the nearby scrub brush.

The cropped vegetation of a dog town also appeals to the mountain plover, which is endangered in Canada and a species of special concern in Montana. The Fish and Wildlife Service was going to list it as endangered in 1995, but a congressional moratorium on new listings stopped them. The plover prefers to nest in short-grass areas where sagebrush is present, a unique aspect of prairie dog towns.

In the old days, I might also have spotted a ferruginous hawk waiting patiently for a prairie dog to stray from its hole. Today, signs of the once abundant bird are rare, except near the few surviving towns.

Again in the old days, as evening approached, I might have seen a swift fox cruising through the town. But I'm not going to see one now. The fox followed the black-footed ferret toward extinction. Only some small pockets survive in South Dakota in prairie dog country.

If my eyes were sharp enough, and my patience great enough, I might have spotted at this one town near the Missouri Breaks in north-central Montana, 158 other animals that live, feed in, or occasionally visit prairie dogs towns, including the bison, bobcat, badger, pronghorn antelope, elk, golden eagle and many neotropic birds that nest there. Add to that the 37 families of insects that have been identified in the towns. A huge diversity of life, all depending to some degree on the prairie dog for survival.

But today there is little activity. I don't know the history of this town - I don't know if the majority of its population has succumbed to plague, or been shot, or been poisoned. All I do know is that without the dogs, the other species are gone or scarce, and a lonely country is even lonelier.


Mark Matthews writes from Missoula, Montana.


There is a group in Denver, Colo., which intervenes on behalf of prairie dogs routinely killed by developers: The Prairie Ecosystem Conservation Alliance traps the critters humanely, then takes them to safe haven at the Plains Conservation Center in Aurora, Colo. Contact PECA at P.O. Box 370264, Denver, CO 80231.

Note: the opinions expressed in this column are those of the writer and do not necessarily reflect those of High Country News, its board or staff. If you'd like to share an opinion piece of your own, please write Betsy Marston at betsym@hcn.org.