probably, i wouldnt see why the wouldnt

No...they hold it until they can find a restroom close by.

no..they sprinkle sand

If any animal or non animal has kidneys, they urinate.

I asked this question, and I want to clarify it. Since there's very little water in the desert, I thought perhaps the animals would not waste it, and therefore have no excess water to release. So they wouldn't urinate. I was wondering if anyone knew whether this was true.

I don't think Kangaroo rats urinate.

Lack of water creates a survival problem for all desert organisms, animals and plants alike. But animals have an additional problem -- they are more susceptible to extremes of temperature than are plants. Animals receive heat directly by radiation from the sun, and indirectly, by conduction from the substrate (rocks and soil) and convection from the air. The biological processes of animal tissue can function only within a relatively narrow temperature range. When this range is exceeded, the animal dies. For four or five months of the year, the daily temperatures in the desert may actually exceed this range, called the range of thermoneutrality. Combined with the scarcity of life-sustaining water, survival for desert animals can become extremely tenuous. Fortunately, most desert animals have evolved both behavioral and physiological mechanisms to solve the heat and water problems the desert environment creates. Among the thousands of desert animal species, there are almost as many remarkable behavioral and structural adaptations developed for avoiding excess heat. Equally ingenious are the diverse mechanisms various animal species have developed to acquire, conserve, recycle, and actually manufacture water. The mechanisms some desert animals have evolved to retain water are even more elaborate. They range from simple to physiologically complex. Some retain water by burrowing into moist soil during the dry daylight hours (all desert toads). Some predatory and scavenging animals can obtain their entire moisture needs from the food they eat (e.g., Turkey Vulture) but still may drink when water is available. Reptiles and birds excrete metabolic wastes in the form of uric acid, an insoluble white compound, wasting very little water in the process. Mammals, however, excrete urea, a soluble compound that accounts for considerable water loss. Most mammals, therefore, need access to a good supply of fresh water, at least every few days, if not daily. Desert creatures derive water directly from plants, particularly succulent ones, such as cactus. Many species of insects thrive in the deserts this way. Some insects tap plant fluids such as nectar or sap from stems, while others extract water from the plant parts they eat, such as leaves and fruit. The abundance of insect life permits insectivorous birds, bats and lizards to thrive in the desert. Some desert creatures utilize all of these physical and behavioral mechanism to survive the extremes of heat and dryness. Certain desert mammals, such as Kangaroo Rats, live in underground dens which they seal off to block out midday heat and to recycle the moisture from their own breathing. These ingenious rodents (there are a number of species) also have specialized kidneys with extra microscopic tubules to extract most of the water from their urine and return it to the blood stream. And much of the moisture that would be exhaled in breathing is recaptured in the nasal cavities by specialized organs. If that weren't enough, Kangaroo Rats, and some other desert rodents, actually manufacture their water metabolically from the digestion of dry seeds. These highly specialized desert mammals will not drink water even when it is given to them in captivity! These are just a few examples of the ingenious variety of adaptations animals use to survey in the desert, overcoming the extremes of heat and the paucity of water.

Oregon...sorry about my earlier smartass answer, I was not trying to be mean, I just thought the question was funny. Desert animals do urinate but a LOT less often than other animals. Defecate less too. I read somewhere that some desert animals urinate through perspiration.

First of all, I'm wondering how you have the time to wonder that! :) I'm assuming they would... if they don't have some access to water, they would die. If they weren't urinating, it's a sign of lack of kidney function...which I don't think would be a good sign either.