Source: D4K: “Desert Habitat"
Visit the D4K companion Web site to learn more about Desert Habitat: D4K: “Desert Habitat"
In this video segment from IdahoPTV's D4K discover the similarities and differences between warm and cold (or high) deserts, like those found in Idaho. The incredible plants and animals which live in the desert have many adaptations for survival in the dry heat.
[JOAN CARTAN-HANSEN] There are two main types of deserts - warm deserts and cold deserts. Warm deserts like this one in Arizona get what little moisture they receive in the form of rain in the summer and fall while cold deserts get moisture in the form of snow in the winter. Idaho's deserts are considered cold deserts. They are also called high deserts because they exist at higher altitudes.
But even the wettest deserts get less than 10 inches of moisture each year. This lack of water forces plants and animals to adapt to desert life in some unique ways. Plants that have adapted by altering their physical structure are called xerophytes. Xerophytes such as cacti usually have a special way of storing and conserving water. Cactus stores water in its fat stem. Many other desert trees and shrubs have adapted by reducing the size of their leaves to eliminate transpiration or the loss of water to the air. And some plants like sage brush also have miniature hairs on their leaves to help further conserve moisture.
Wildlife too must adapt to this challenging environment and desert animals have an additional problem. They are more susceptible to temperature extremes than plants. Fortunately, most desert animals have developed ways to solve heat and water problems. Many animals - especially mammals and reptiles - avoid the heat of mid-day and only become active at dusk and dawn.
These animals are said to be crepuscular. A good example of crepuscular reptile is the rattlesnake. In the middle of the day rattlesnakes curl up under cover. They hide in pockets of cool shade, hidden under hot desert rocks. Only in the early mornings or late afternoons will rattlesnakes venture outside. For this reason humans seldom encounter them.
Some desert animals go one step further and only come out in the cool temperatures of the dark night. These animals are said to be nocturnal. A bat is a good example of a nocturnal animal. Bats sleep in cool caves during the day and come out after the dark to feed on their favorite meal of insects.
Certain desert lizards like this leopard lizard are active during the hottest part of the day but they combat heat by moving extremely fast over hot surfaces and stopping only in cool islands of shade.
Birds of prey, also called raptors, are some of the desert's most efficient hunters. Eagles, hawks and falcons survey the land with keen eyes. Their prey - small mammals and ground squirrels - hide in burrows beneath the desert soil. These sage grouse live and nest in the sage brush deserts of southern Idaho.
During the mating season the males wake early and at dawn form an elaborate mating dance strutting about and fanning their tails, displaying feathers arranged in a striking pattern of black and white. This elaborate display is mainly for the benefit of the female grouse who watch the spectacle from the sidelines, hidden safely beneath the cover of sage brush.
Pale colors on these rocky mountain big horn sheep not only insure that the animal takes in less heat from the environment but help make it less visible to predators in the bright desert surroundings.
So while some say the desert is an acquired taste, if you look carefully you may find yourself hooked on its quiet beauty.
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