Animals

Animals

Colorado National Monument's varied terrain attracts many animals to live, nest, or hunt within its boundaries. Among mammals, the mule deer are the largest commonly sighted by visitors. However, coyotes, mountain lions, bobcats, and desert bighorn sheep are also occasionally seen by a lucky visitor. Smaller mammals like foxes, desert cottontails, squirrels, and other rodents are often seen scampering off the sides of the Rim Rock Drive or hiking trails.

The towering walls of the various canyons in the monument are a perfect place for various raptors and songbirds to raise their young. Golden eagles, red-tailed hawks, and turkey vultures often soar aloft on the air currents, Gambel's quail scurry across the trails, and the calls of the mourning dove and the canyon wren echo in the canyons. The various overlooks are excellent places to watch the acrobatics of the white-throated swift just below the rim. Bright blue scrub jays are a common and colorful sight throughout the monument.

Reptiles are generally seen in the monument from early March to late October. They are most visible in May and June, and are active on warm, sunny days and mild evenings. Watch for yellow-headed collared lizards or the plateau whiptail, especially during late morning or late afternoon hours; they often are seen sunning themselves on the warm rocks. Snakes do exist in the monument, but only one, the midget-faded rattlesnake, is poisonous and is rarely seen.

Following summer thunderstorms, listen for calls of frogs or toads in the canyons. Amazingly, there are several species of amphibians that thrive despite the monument’s semiarid environment. Their ability to burrow underground and remain dormant for brief or extended periods of time gives them a high tolerance to temperature extremes and drought. Following heavy rains, several species, like the red-spotted toad or the canyon tree frog, surface to take advantage of seasonal water sources. As most of the species are primarily nocturnal and well camouflaged, they are rarely seen, but if you listen, you may hear them calling late in the evening.

Mammals

Most of the mammals that live in Colorado National Monument on a year-round basis have evolved unique physical and behavioral adaptations to survive in this semiarid ecosystem. Annual precipitation at Colorado National Monument is less than 12 inches a year with summer temperatures ranging from the high 90s to over 110 degrees in the canyons. Winters are generally mild with lows occasionally dropping to the single digits. These extremes, combined with a minimal amount of water, can prove to be challenging to the wildlife that make this their home.

A majority of mammals like the desert cottontail, mule deer, coyote, porcupine, jackrabbit, and many songbird species are crepuscular, meaning they are only active in the early morning hours or late in the evening when temperatures are cooler and there is just enough light to forage for food.

Others, like the ringtail, fox, bobcat, mountian lion, several species of bats, and a variety of small desert rodents, are nocturnal, emerging at night and are rarely seen.

Mammals like rock squirrels, antelope squirrels, and chipmunks are active during the daytime or "diurnal" and are a common sight.  Of course there is the occasional rare and exciting report of a mountain lion wandering in one of the canyons or, as was the case in the summer of 1997, a black bear sleeping in Window Rock!

Over 40 species of mammals have been recorded within the boundaries of the monument; however, not all are year round residents. The desert bighorn sheep are frequently seen near the Balanced Rock area on the west side of the park. Elk have also been known to travel down to the monument from the higher elevations during the winter months.

Common Mammals in the Monument

Coyote (Canis latrans) These medium-sized members of the canid family are commonplace in the American West. Coyotes average about 15 inches in height (at the shoulder) and weigh about 40 pounds. They are primarily nocturnal, but they can sometimes be spotted roaming in daytime. They will eat almost anything, but small rodents and rabbits typically comprise the bulk of their diets. Coyotes breed in the winter and typically give birth to five to ten pups in early spring. This inquisitive and opportunistic animal is the best runner of the canids, reaching speeds up to 30 mph. They are able to leap up to 14 feet in a single bound.

Grey Fox (Urocyon cinereoargenteus) – The grey fox ranges through most of the southern half of North America. These small members of the canid family resemble small dogs with bushy tails. Grey foxes are solitary hunters and eat a wide variety of food, including rabbits, voles, mice, and birds; they also supplement their diets with fruits when they are available. Grey foxes are unique among canids in that they are able to climb trees. They have strong, hooked claws that allow them to scramble up trees to avoid predators or to get fruit. Grey foxes are nocturnal and den during the day in hollow trees, stumps, or old burrows. 

Ringtail (Bassariscus astutus) – This cat-sized carnivore resembles a small fox with a long raccoon-like tail. Its tail is typically as long as its body and is banded with 14 to 16 alternating black and white rings. Ringtails live in a variety of habitats, but have a preference for rocky areas, canyon walls, and talus slopes. They are expert climbers, capable of climbing vertical walls. Ringtails are nocturnal and spend most of the day asleep in dens, typically in rock crevices and hollows. They eat a wide variety of animals, including small mammals, birds, reptiles, amphibians, and insects, but they also supplement their diets with fruit, including juniper berries, in winter.

Rabbits and Hares (family Leporidae) – Worldwide, there are almost 50 species of rabbits and hares, most of which are native to North America. At Colorado National Monument, cottontail rabbits and jack “rabbits” (they are actually hares) are common. They are generally grazers, feeding on grasses and other plants, but they may also feed on twigs and tree bark. While these two groups of mammals are often confused, they are actually quite easy to identify. Rabbits are generally smaller and have relatively smaller ears. Hares have very large ears and long hind legs. Typically, rabbits are weak runners, and when threatened, they often scamper into thick brush. Hares, on the other hand, are more adapted to open country, are very strong runners, and usually burst into bounding runs when threatened. Both groups have high reproductive rates; their litters typically consist of up to eight young, and can be as large as 15.

Prairie Dog (Cynomys ludovicianus) – Prairie dogs, while common on the plains and plateaus of the western U.S., are rare in Colorado National Monument. These small, ground-dwelling rodents are closely related to marmots and ground squirrels, and grow to about 15 inches in length. Prairie dogs are highly social and live in “towns”, sometimes comprised of thousands of individuals. They are named for their bark-like yips that serve as warning cries. Prairie dogs live in holes dug into the ground, sometimes 10-15 feet deep. They collect the dirt removed from their burrows and construct raised hills around the entrance holes to prevent flooding. They are active during the day, and they spend most of their time grooming each other and defending family territorial boundaries. They eat herbs and grasses that grow within range of their burrows.

Porcupine (Erethizon dorsatum) – These large members of the rodent family have long, pointed spines, or quills, growing from their backs and sides. The quills have needle-sharp ends and hundreds of barbs. They are loosely attached and can be raised by the muscles of the skin. Porcupines can be found in wooded areas throughout North America, from Alaska to Mexico. They are herbivorous, and often eat the bark of trees. They grow to a length of about 26 inches, and have short tails and brownish hair that almost conceals their two to six inch quills.

Bobcat (Lynx rufus) – These medium-sized cats live in shrubby country and broken forests and are fairly common in the monument. Bobcats are about 25-30 inches in height (at the shoulder), and can weigh up to 60 pounds. They are gray-brown with distinctive black spots, and have short “bobbed” tails that are about four inches long. Bobcats are skilled predators, and their prey include rodents, rabbits, hares, squirrels, and birds. They are excellent climbers and often wait in trees to pounce on their prey. Bobcats are territorial, and they mark their territories with urine, scent from anal glands, and feces deposited on the ground during their frequent territory patrols. Bobcats often wander large distances, sometimes 25-50 miles, but normally stay within a few miles of their territories. The territories of males are larger than those of females. While bobcats are solitary in nature, the two sexes do remain together briefly during the breeding season, and it is not unusual for the male to help provide food for the kittens. They usually mate in late winter and kittens are born in early spring. The kittens weigh less than one pound at birth and are blind and completely helpless. They normally venture from their dens at the age of five weeks, and by nine months, are nearly independent.  

Mountain Lion (Felis concolor) – Mountain lions, also commonly known as cougars and pumas, range from northern Canada to the tip of South America. They are large, powerful cats, standing 28 inches (at the shoulder) and weighing up to 200 pounds. Despite their large size, they are very quick and agile; mountain lions can cover up to 23 feet in a single leap. However, because they tire quickly, they must be accurate; if prey is able to survive initial attack, it will normally escape. They generally hunt in the daytime by stalking and pouncing on the back of their fleeing prey. Once they power their prey to the ground, they normally deliver a fatal bite to the back of the neck. Their principle food source is deer. Mountain lions have very large territories that rarely overlap. On the unlikely chance that two of these solitary cats meet, they rarely fight to defend their own territories. During the breeding season, male and female mountain lions hunt together and sleep next to each other. The female gives birth to cubs in a well hidden den, usually between rocks or in a cave. The cubs are spotted at birth, and they lose these spots at about six months of age. Although they can hunt for themselves at nine months of age, they normally stay with their mothers for two years. There are many tales of the savagery of mountain lions, and their attacks on people, but unprovoked attacks are very rare. They usually avoid contact with humans, but if cornered, they can be very dangerous, and should be treated with respect and caution.

Birds

The pinyon-juniper woodland that dominates most of this area provides an essential habitat for a wide diversity of birds. At least 54 breeding songbird species and nine breeding species of raptors have been identified in the monument. Several other species are known to pass through during migration and winter months. Recognizing the significance of this area, Colorado National Monument was designated as an important bird area (IBA) by the National Audubon Society and the American Bird Conservatory on May 10, 2000.

Birds can be challenging to identify and generate much curiosity. To aid the beginning birdwatcher, the Colorado National Monument Association bookstore offers a broad selection of books and a checklist of common park birds.

Amphibians

The semiarid environment of the Colorado National Monument may seem like an unusual place to find amphibians, but in fact, there are several species of frogs, toads, and a rarely seen salamander that reside in the monument. Some amphibians have the ability to remain dormant in underground burrows, sometimes for more than a year, enabling them to survive in harsh, dry environments. Emerging from their burrows during the rainy season they take advantage of intermittent streams and potholes. The raucous vocalizations heard, usually in the late spring and summer evenings, are emitted by male toads and frogs trying to attract mates and quickly reproduce while conditions are optimal.

Amphibians are very sensitive to their terrestrial and aquatic environments, changes in either can effect their survival and propagation. Like the “canary in a coal mine”, amphibians are considered indicator species that serve as monitors of the environment.  Over the last several years scientists have documented an alarming decline in amphibian populations, some to the point of extinction. While a specific reason for this trend is unknown, there are several possibilities being studied. Pollution, acid rain, global warming, loss of habitat, and non-native predators / competitors are just a few of the changes that may be causing the declining populations. 

Amphibian populations within Colorado National Monument are greatest along small perennial streams found in No Thoroughfare and Ute Canyons. Visitors can help amphibians by not disturbing water resources and reporting sightings at the visitor center.

Reptiles

Reptiles are among the most conspicuous animals found in the monument and are seen from early March through late October, being most active in May and June.  According to the latest survey conducted, nine species of lizards were identified as monument residents.

Lizards are most active on warm, sunny days and temperate evenings, and are commonly seen sunbathing on rock exposures throughout the park. In colder temperatures they hibernate, relying on food stored as fat in their tails for nutrition.

Nine species of snakes have been identified in the monument but because they are most active at night, they are rarely seen. The midget-faded rattlesnake, a subspecies of the western rattlesnake,   is the only poisonous snake found in the monument. This snake, like all other snakes found here, is not aggressive and avoids human contact.

Desert Bighorn

Desert bighorn sheep are among the most intriguing mammals of canyon country. They are wary of human contact and blend so well into the terrain they inhabit that sightings are a special event. Once in danger of becoming extinct, the desert bighorn are making a tentative comeback in southeast Utah due to a comprehensive reintroduction effort by the National Park Service. With one of the few remaining native herds, Colorado National Monument has been a critical area for restoration efforts.

Desert or Nelson's bighorn sheep (ovis canadensis nelsoni) are considered by most biologists to be a unique subspecies. Unlike their Rocky Mountain cousins, desert bighorn have adapted to hot, dry climates, and have longer legs, lighter coats and smaller bodies. Bighorn sheep are common in American Indian rock art, an indication of their presence and prominence in indigenous cultures.

Accounts from European explorers in the late 1600s estimate that more than two million desert bighorn once roamed the southwest. However, by the late 1800s bighorn sheep had disappeared or declined in many areas. Extremely vulnerable to diseases from European livestock, herd after herd of wild sheep were decimated by pathogens like scabies (an ear mite) and anthrax (a bacterial disease) introduced by domestic sheep. Bighorns were also killed by early explorers, settlers, and trophy hunters.

Increased human activity, competition with domesticated cattle and sheep for food and development are the biggest threats to the desert bighorn sheep today. For remaining herds to survive, intensive management and conservation measures may be necessary. Present and future protection of undeveloped land and wilderness areas are key to the species' survival.

Insects, Spiders, Centipedes, Millipedes

Insects are everywhere in Colorado National Monument. But depending on the season, the elevation, the weather, and even the time of day, visitors may see hundreds or only a few insects.

At lower elevations and in the canyon bottoms, insect numbers and diversity are highest in spring when the desert flowers bloom. A wet spring will have not only more flowers but many more insects than a dry one. Another peak in numbers is reached in early fall when the rabbitbrush puts forth its many golden flowers. In the pinyon-juniper forest, insect numbers gradually increase and probably reach their peak in late summer.

Some insects, like moths, tend to be common throughout the warm months; while others, like the May and June Beetles, or some of the butterflies are found for only a few weeks in the spring.

The weather plays a large role either in controlling insect numbers or having the opposite effect and allowing their numbers to explode. Many insects will survive a warm winter, but be killed in a very cold one. Summer rains that soften the hard ground and make it easier to dig tunnels often cause the ant colonies to swarm and thousands of winged queens and drones take to the air to start new colonies.

For the visitor who takes the time to stop, look closely, and listen, there are always some insects or other wildlife to be seen or heard.