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The Red Rock Canyon NCA may seem rugged and desolate at first glance, but a closer look reveals an area teeming with wildlife. The desert often brings to mind snakes and lizards, but mammals too, inhabit these lands. In fact, over 45 species of mammals occur in the Red Rock Canyon NCA. The presence of cool temperatures, perennial water and a variety of plant species in the sandstone canyons provide escape from desert heat and aridity, making the conservation area a suitable habitat for wildlife. Desert mammals can be divided into four broad categories: the carnivores (meat eaters), small and large herbivores (plant eaters), and insectivores (insect eaters). All must conform to specific behavioral traits to survive in such arid lands. Most desert mammals are nocturnal, which means active during the night. Temperatures are lower and humidity is higher then and the animal loses less water through perspiration and breathing. Besides being nocturnal, many adopt other water-saving habits as well. Let's look at some of the ways that mammals have adapted to survive in this harsh desert environment. CARNIVORES Carnivores are predators and chiefly eat meat, although some will consume plants. They will drink water when it is available, but are not dependent on it since the moisture-rich flesh of their prey satisfies their water needs. This group includes such well known members as the coyote, kit fox, gray fox, bobcat and mountain lion. A member of the dog family, the coyote resembles its domestic cousins except that its nose is more pointed and its tail is bushier. The coyote is a very vocal mammal, communicating through barks and howls. Its scientific name, Canis latrans, literally means 'barking dog." In addition to being a predator, the coyote is an omnivore (plant and animal eater) and a scavenger. This varied diet allows the coyote to exist under the desert's harsh conditions and is one reason why the coyote is now the most widespread mammal in the United States. It can be seen occasionally from the scenic loop drive. The gray fox also has a varied diet, but not to the extent of the coyote. It hunts widely at night, subsisting on rodents, ground squirrels, birds, wild fruit, insects, amphibians and small reptiles. It is an adept climber and will often search for food or escape danger by climbing trees.
The bobcat, the most abundant cat in the southwestern United States, also resides in the area. It spends most of the day under bushes, usually in rock fractures or canyons. The bobcat has little endurance and stalks prey rather than chasing it. It primarily eats rodents, but will take rabbits, ground-nesting birds, and occasionally, a young deer. Because of its nocturnal nature, it is not often seen unless disturbed from its daytime resting place. SMALL HERBIVORES This group includes the rodents, rabbits and hares. As herbivores, they primarily eat plants, although some will supplement their diet with insects and dead or decaying flesh. They rely on their diet to satisfy both their food and water needs. Some small herbivores found in the conservation area are the antelope ground squirrel, kangaroo rat, pack rat, blacktail jack rabbit and desert cottontail. Although most mammals in this group are nocturnal, the antelope ground squirrel is undaunted by the desert sun. This rodent is often seen from the scenic loop drive during the hottest parts of the day, with its white tail held close over its back as it runs about. To cool off, it may go below ground but usually flattens its body against the soil in a shaded area and loses heat through conduction. Although it can drop its body temperature by as much as seven degrees in this manner, it can lose 13 percent of its body moisture per day. To make up for this water loss, it feeds on green leaves and drinks early morning dew. The kangaroo rat, named for its habit of hopping rather than running, does not drink, use dew or eat succulent foods. Its only source of moisture comes from metabolic water, water produced through the digestion of food. However, digestion creates very little water, so the kangaroo rat must conserve every drop. Its nasal passages are much cooler than its internal body temperature. Air which passes through these nasal passages cools and water condenses on the mucous membranes, where it is absorbed. The kidneys of the kangaroo rat are also very efficient, producing a urine four to five times as concentrated as human's. Additionally, the kangaroo rat has adapted behavior to survive in the desert. It spends the hot days underground where the temperature is 30 °F (17 °C) cooler and the humidity is much higher. Seeds are stored in the burrow where they absorb additional moisture before being eaten.
LARGE HERBIVORES Mule deer, desert bighorn sheep and burros can also be found within the conservation area. Large herbivores derive some moisture from their plant food but unlike the small herbivores, also need drinking water periodically. The mule deer prefers foothills with low scrub growth or thick growth along washes. By late evening it leaves its daytime hiding place to find water in seeps and springs.
INSECTIVORES This group includes bats and shrews and primarily consumes insects. Bats are separated from all other mammals by possessing the power of true flight. To escape the heat and avoid competition with birds, they are active only at night. Seldom using their vision, they rely on echo location to find prey and avoid obstacles. To echo locate, the bat emits a series of chirps and clicks from its throat. These sounds reflect off nearby objects, informing the bat of moving insects or stationary obstacles. The odd facial structures of many species aid in the reception of the reflected sound. Although the majority of bats eat insects, a few feed on the nectar of flowers. These bats have long tongues with hair or bristles on the tip to allow them to reach in to gather nectar. Thus, bats serve not only to control disease-carrying insects, but act as pollinators as well. Shrews are very small mammals which spend most of their lives underground. They have reduced eyes and rely on their sense of smell and touch to locate insects. A voracious eater, the shrew is also a ferocious hunter, for to be without food for more than six or seven hours means certain death. Being an underground dweller, they are rarely seen. Many more mammals live in the conservation area. Each has it own interesting adaptations for desert survival. Take the time to observe and learn about the mammals and other life forms in the area. Only through close observation can the desert and its associated plant and animal life be truly appreciated |
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