On April 20, Durango Nature Studies will hold its fourth annual Earth Day 5K and Family Fun Run Celebration at For the Birds. It will begin at 11 a.m.
In honor of our event, and as a way to motivate people to brush off their running shoes, I devote this column to the fastest animal in Colorado the pronghorn.
The pronghorn is a native to North America and should not be confused with the antelope, which lives in Africa and is a member of the cow family. Pronghorn, rather, are the only mammal that has branched horns over a bony core. Males and females have a pair of short horns on top of the head. The females horns are small, usually only a bump. In contrast, the males horns are around 10 to 12 inches long. They also have a unique shape because, unlike other ungulates, a pronghorns horns point backward. The horns extend straight up and then curve toward the rump. At the front of the horn is a small notch or prong that points forward; hence the name, pronghorn.
Pronghorns generally live in grasslands and semidesert shrublands on rolling topography that affords good visibility. They are most abundant in short-grass or midgrass prairies. One of the most common places to see herds of pronghorn is between Durango and the Front Range in South Park near Saguache.
Pronghorns depend on their strong vision to communicate. If a pronghorn spots a predator, it raises its white rump hairs, causing this white patch to become more visible to other pronghorns. This signal means to be on the alert danger is near.
Pronghorns are herbivores. They eat grasses, forbs, sagebrush and other prairie plants. Pronghorns digest their food twice. After they swallow food, it passes through the stomach and then the pronghorn regurgitates it. This process allows the pronghorn to break the plant material into smaller pieces so that more nutrients are absorbed. The regurgitated food is called cud. They seldom drink water because they receive most of their water from the plants they eat. In this way, they are specifically suited to their semidesert environment, allowing them to exist alongside cattle and, at one time, alongside bison.
After the turn of the 20th century, pronghorns were nearly extinct because of unregulated hunting. Today, the pronghorn is regulated as a big-game animal. Its total population in Colorado is around 50,000. One of the most fascinating things about the pronghorn is its migration pattern. The pronghorn has the longest land migration in the continental United States, migrating a grueling 300 miles over fences, highways and developments between the upper Green River Basin and Grand Teton National Park.
Now, on to the topic everyone is interested in ... speed. The pronghorn is North Americas fastest animal, running at speeds up to 60 miles per hour. Although pronghorns arent quite as fast as cheetahs, they can maintain their speeds for a longer period of time.
Sixty miles per hour is a bit daunting for us humans, but hopefully the speed of this North American native can inspire runners or would-be runners to carve a few seconds off their time, or at least run for the joy of it as a way to celebrate being part of the natural world this Earth Day. If you are inclined, pick up your race registration at Browns Sport Shoe, Backcountry Experience or online at www.durangonaturestudies.org/earthday.htm.
sally@durangonaturestudies.org or 382-9244. Sally Shuffield is executive director of Durango Nature Studies.
