Denver’s Street-Smart Prairie Dogs

Researchers explore why members of one species are thriving in urban areas while rural populations dwindle

A family of black-tailed prairie dogs practices their vigilance from their colony in Highlands Ranch. (Morgan E. Heim)

Prairie dogs start barking bloody murder and scramble for their burrows as a hawk glides fast and low over the colony. The emergency broadcast gives the rotund fur balls ample warning. For the raptor, it’s wishful thinking.

“Whoa! Now would you look at that,” says Kevin Crooks, a biologist at Colorado State University. Crooks, tall and wiry with an easy grin, points to the north. A second raptor sweeps lazy circles under the morning sun, and a third perches atop a fake tree trunk that was erected here to attract prairie-dog-eating birds.

We’re standing on a narrow strip of prairie running through the community of Highlands Ranch just south of Denver. Here, tucked among a high school football field, a paved running trail and rows of tidy, two-story cookie-cutter houses, lives a colony of about 30 black-tailed prairie dogs.

Danger averted, the prairie dogs once again peek from their burrows and start scampering about, touching noses in greeting and browsing on grasses and flowers. But something’s awry. Wooden stakes mark several mounds, and many of the burrow openings are masked by chicken wire. The stakes are numbered, and by all appearances, so are the prairie dogs’ days in this section of Highlands Ranch.

The stakes, it turns out, are part of a passive relocation project run by the Douglas County Citizens for Wildlife, and an attempt to save the colony. These prairie dogs verge on taking up residence in people’s yards, and the hope is that by blocking the burrows the animals will move away from houses and into undeveloped land where they can continue to go about their prairie dog lives.

If the critters fail to get the message, Highlands Ranch will resort to lethal control, which involves either fumigating the colonies or capturing and sending prairie dogs to raptor and black-footed ferret recovery programs, where they will be used as food. This neighborhood illustrates the challenge of trying to balance human communities with prairie dog ones, and it’s a coexistence that has pitted many Westerners against the diggers, and each other, for decades.

Black-tailed prairie dogs are vanishing from the West. In the past 200 years, their numbers have dwindled to just 2 percent of their estimated historic population because of introduced plague, recreational shooting and development. Colonies “are just blinking out because of development,” says Crooks. “There’s no other word for it. Prairie dogs have been exterminated over vast ranges of their habitat.” The black-tailed prairie dog is currently being considered for protection under the federal Endangered Species Act. It would be the third of five prairie dog species in the United States, after the Mexican and Utah prairie dogs, to be listed.

When one thinks of potential endangered species, it’s not common to look in the backyard, never mind territories that include a lot of traffic, buildings and city slickers. But black-tailed prairie dogs are bucking trends and taking advantage of urban green spaces—rather successfully. In places like Denver and Boulder, it’s nearly impossible to walk, bicycle or drive without tripping over or flattening one of these vocal critters.

This unusual existence brings with it an unusual ecology, which until now has remained largely mysterious. Previous research on prairie dogs stuck mostly to rural colonies, but thanks to the curiosity of one of Crooks’ former graduate students, Seth Magle, researchers are learning about the urban variety. “It’s very important for a number of reasons,” says Magle. “Urban areas are expanding. Protected areas are not.”

Magle started studying the secret lives of urban prairie dogs in 2002. He mapped their communities in Denver and found unexpected behaviors. Perhaps most startling of all was the robustness of this wildlife in a limited environment. Magle discovered that city prairie dogs lived in communities on average five times more crowded than rural colonies. Contrary to the expectation that confined and rapidly growing wildlife populations would crash because of population pressures like disease or competition for food, Magle found that prairie dogs seemed to get along pretty well in tight quarters.


Comment on this Story

comments powered by Disqus