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| Deserts areas
have very low rainfall and little surface water. There is little soil, vegetation
or animal life. Most are very hot, but whether hot or cold, conditions are harsh.
The landscape may be stony plains, sand or bare rock. Weathering may create spectacular
landforms. Deserts cover vast tracts of the planet's surface and their area is increasing due to desertification. Climate changes, unpredictable droughts and removal of vegetation by harvesting, ploughing or overgrazing can cause the spread of deserts. Once plants disappear the soil dries out and erodes, then vegetation cannot re-establish. |
The Zoo's desert
habitat is located in the Desert House.
It has been created inside a giant glasshouse to show three types of desert environment
- rocky ravine, dry plain and oasis. It is home to a large number of free-flying
birds originating from deserts all around the globe. It is also home to a number
of reptiles including the venomous Gila monster and beaded lizard.
The desert glasshouse also contains two large artificial termite mounds (without
termites). One mound is a mealworm dispenser and the other is a nest mound for
the hooded parrots. Both were designed and built by the bird staff and resulted
in a prestigious award from the University Federation for Animal Welfare in 1998.
Another desert animal, the Bactrian camel, may be seen at the Zoo in a large, outdoor enclosure.
Plants in deserts
Desert plants include long-lived bushes, succulents and short-lived plants that
flower once before setting seed. These seeds may remain dormant for years. Desert
plants have evolved many adaptations to store water and to prevent water loss.
Cactus and Euphorbia can appear almost identical although they are from unrelated families. This is a case of parallel evolution, with both groups having adapted to deal with desert conditions in a similar way. Swollen stems store water and have spines rather than leaves to reduce water loss and protect the plant from animals. The outer covering may be woolly or waxy which gives protection from sun, wind and dehydration.