Rocky Mountain Arsenal National Wildlife Refuge

arsenalvistaA short distance from downtown Denver, in the heart of Commerce City, you’ll find the Rocky Mountain Arsenal National Wildlife Refuge. At first glance, it’s an unlikely site for wildlife. But this refuge reveals a story unlike any other.

On nearly 17,000 acres, a 27-square-mile site, officials plan a theme park designed around short-grass prairie. Since 1992, when Congress passed an act designating the Arsenal as a refuge, a chapter of history closed. The Arsenal once was the manufacturing site of chemical weapons. Then it became an industrial site for pesticide production. Both endeavors marked the Arsenal land as unsafe for housing or business. Only one possibility remained: set the land aside for wildlife, where a new chapter of history could unfold.

arsenalboardwalk8477Now the Arsenal hosts nature programs for schoolchildren, bird watchers, hikers, fishermen, photographers and those who want to get away from the jangle of city noises. For harried urbanites, it’s 11 miles from downtown Denver and open year around. Still, on a late winter’s day, only a handful of people show up. The guide on a shuttle bus tour points to a Swainson’s hawk, magpie nests and tree swallows as a large coyote lopes by. The coyote paws at a prairie dog home, unconcerned about our presence. Not far away, a pair of burrowing owls rock back and forth, oblivious to passersby in what may be the largest group of burrowing owls on the Front Range. They’ll feast on baby prairie dogs and take over the prairie dogs’ underground homes. The prairie dogs squeak a protest nearby.

arsenalwater8551Animals at the Arsenal include the usual suburban creatures: deer, geese, raccoons and rabbits. But in mid-March of 2007, 16 bison arrived. These were not the usual bison that farmers raise for meat. They were culled from a federal bison reserve in Montana that held a small number of bison known to be genetically distinct. These represent the last remnants of original North American bison. They are distantly related to small herds of Wood Bison in Canada and Wisent Bison in Eastern Europe.

arsenaldeer8462Although the reserve cannot promise that every bison in their reserve has no cattle genes, DNA tests prove that the small group may be the only bison left of that unique species.

Nearly 200,000 bison are raised on ranches, mostly for meat consumption. But ranchers who introduced bison intermingled them with beef cattle. The flavor of genetically pure bison was too strong, too lean, consumers told them. Interbreeding the bison with cattle improved the taste, and, in return, bequeathed some hardy bison genes to the less robust cattle. Bison required little care, rarely sickened and managed fierce storms far better than our European-introduced cattle. Today cow and bison graze alongside each other on ranches and the bison looks exactly like a bison. But cattle genes are not detected easily, except by experts.

arsenalgeese8470The Sulleys Hill National Game Preserve opened in 1904 under President Theodore Roosevelt with the mandate to protect the last of our bison. Now the preserve has sprinkled a few grassland refuges in the Midwest with small numbers of this legacy. Thirteen females, some pregnant, and three bulls were driven down to the Arsenal and released into a fenced pen. They will have two calves every three years if all goes well. Although single births are most common, occasionally twins are born.

Fifty and more years ago, Commerce City appeared far away from population centers but close enough to ship lethal cargo for the military. Nearly 5,000 workers built a chemical arsenal for wartime. But when peace arrived and treaties forbade the manufacturing of chemical weapons, the site was leased for pesticide production. Eventually, the miseries of a toxic dump shut down the chemical city, resulting in a problem for both military ownership and civilian surroundings.

arsenaleagleThe arrival of bald eagles changed everything. In 1987, a biologist met a U.S. Army general at the airport, shuttled him around the Arsenal site and pointed out a number of bald eagles nesting. Bald eagles were endangered and many despaired over the demise of our national symbol. The sight of several pairs of eagles nesting was dramatic enough to convince the general that the Arsenal could only be a wildlife refuge.

Since then, the Arsenal has changed dramatically. First there were efforts to contain toxic soil. A mountain of rubble gathered from torn up defunct airport runways lies in a heap. It’s to staunch toxic chemicals by slowing down their seepage. Wild animals arrived, mostly suburban wildlife fleeing housing developments. Mule and white-tailed deer, raccoons, coyotes and prairie dogs were followed by falcons and waterfowl. The prairie dogs and stocked fish in a small pond feed the birds of prey. Burrowing owls arrived to take over some of the prairie dog homes. Finally the arrival of the bison signaled a new chapter: the introduction of a unique creature not seen around Denver in a hundred years.

Bison once grazed on the short-grass prairie of the Arsenal land. Long before farmers plowed and planted, blue grama and buffalo grasses fed herds of these giant herbivores. Nutritious grasses supplied enough for a bull to weigh 2,000 pounds. At the Arsenal they will have 1440 acres of replanted prairie to satisfy them. For the Arsenal, having such a small remnant of the true bison is a spectacular addition in a wildlife refuge completely surrounded by city life.

“There are two other animals we’d like to have,” the guide suggests while showing off the bison, “pronghorn and prairie chickens.” The lesser and greater prairie chickens are endangered birds that flock to the eastern edges of Colorado, the lesser in the southeast near Campo and the greater in the northeast near Nebraska.

Pronghorn don’t fall into the endangered category but they are skittish and look for a contiguous piece of land where they can run the length of the state and more. Enclosing them into a wildlife refuge cut off from the wide-open spaces won’t be easy. For now, managing the bison is a thrill. The staff takes their responsibility seriously. The shuttle out to the bison stops far enough away to allow privacy for the herd. A bull straggles back from the rest of the tiny herd, a point of concern for the staff. The bull kicked inside the large truck that transported him. In doing so, he injured himself and now stays away from his companions. “The doc says he’s okay,” the volunteer offers, but casts an anxious eye out to the pasture where the bull lies.

Look to the future of the Arsenal and plans are vast. A café, theater and bookstore are just a start. Take a shuttle to the prairie dog home, the water fowl lake, rattlesnake hill, views of Denver, prairie dog colonies, historic places of ancient tepee rings, an eagle watch viewing, an old homestead of settlers and the military locations.

But with all the history of prairie and homesteads, the Arsenal would not exist without a legacy of war and pesticide manufacturing. Soil, water and buildings remain contaminated. And there’s another related refuge slated to open with a history of nuclear plutonium toxicity: the Rocky Flats National Wildlife Refuge. In both refuges, we hope nature can heal what appears sickened forever. Whether or not that is possible, only time will tell.

Rocky Mountain Arsenal NWR, Building 111, Commerce City, Colorado, 80022-1748; 303-2889-0232;; Enter the Refuge at 56th Avenue and Havana Street. Continue 1.5 miles to the Visitor Center and check in.

National Bison Range Website:

Rocky Flats National Wildlife Refuge is not yet open to the public: