Water is crucial to the survival of all living things. We certainly cannot take for granted, however, that we always will have access to fresh water. Only 2.5% of the world’s water supply is freshwater, and only 1% of that is easily accessible. The remainder is trapped within glaciers and snowfields.
The disconnect between the importance and scarcity of water is most acute in desert ecosystems. In fact, deserts are not defined by temperature, but instead by the average amount of rainfall they receive; by definition, deserts receive 9.75 inches of rain (or less) per year. While the Sonoran Desert looks like a jungle compared to many of the world’s deserts, the amount and timing of precipitation and the distribution and availability of standing water determine the number and type of plants and animals that the desert can support.
The water resources of the Sonoran Desert are currently threatened on multiple fronts. We do not yet know exactly how precipitation patterns will sort out with continued global warming, but we do know that droughts have been more frequent and prolonged in recent years than in the past. Urbanization leads to an increased need for ground water, and increasing the pumping of ground water deprives the organisms that depend on this source of water. Fencing and walls, including the existing and proposed border walls, cut off routes to seasonally available water that some species, such as Sonoran pronghorn, depend on.
Water is a scarce and valuable resource in the Sonoran Desert and must be both judiciously shared and sustainably managed to ensure the continuity of this bountiful and unique ecosystem and all of its inhabitants.