Before my trip to Tanzania and Kenya I spent a lot of time in Arizona visiting family. We spent several days hiking through local parks and reserves. On one of these such trips to Estrella Mountain Regional Park while I was enjoying the hidden beauty of such a harsh landscape I found myself thinking about how animals manage to survive in such unforgiving landscapes. This period of contemplation may also have been triggered by having just finished “Cry of the Kalahari” by Mark and Delia Owens in which they spent seven years studying how animals survive in the Kalahari desert.

While the word desert comes from the latin word “desertus” meaning abandoned, it is truly amazing how much life there is hidden within deserts. These extreme ecosystems can be found all around the world. Even the most barren and harsh environments can still support some form of life, although this is typically not seen by the average visitor to these landscapes. Animal life is usually nocturnal in these environments and plants may lay dormant for months or years waiting for those rare and brief periods of rainfall to conduct their life cycles.

Possible source of shade for desert dwelling creatures.

Possible source of shade for desert dwelling creatures.

Desert dwelling animals have adapted to living conditions that are both fierce and beautiful. With searing daytime temperatures very little animal life is found during the day. That being said some critters have developed habits that allow them to stay active during daylight hours. Kangaroos for example have developed the behavior of licking their forearms to coat them in saliva. These areas of their arms have clusters of blood vessels close to the surface of the skin to allow heat to quickly escape as their saliva evaporates. Many other species have developed ways of dispersing heat. These species typically will still lie up in the shade during the hottest times of the day and resume activity in the mornings and evenings when it is cooler.

As night falls deserts come to life. Owls, foxes and other predators begin their hunt by the light of the stars. This is also when most foraging by rodents occurs.

Even as midday temperatures rise these little critters were still active

Even as midday temperatures rise these little critters were still active

Along with the heat a lack of water is the other great challenge for desert dwelling species. For many rodent species metabolic water is their greatest source of moisture. That is they receive the bulk of their water through what is realized during digestion of food. Similarly, brown hyenas in the Kalahari rely heavily on ostrich eggs for water during periods of drought. Cactus can be a very important source of water for many desert ecosystems in the Americas, with many species adapted to feed on cactus. In one of the most extreme deserts of South America the only moisture comes in the form of fog rolling off the coasts which is then trapped in vegetation such as cactus to make it available to animals.

Advertisements