Watering hole for wildlife? : Photos, Diagrams & Topos : SummitPost

Natural water sources are NICE to stumble upon in the desert, but
can have some drawbacks for wildlife. Bedrock tinajas (or tanks) are
naturally occurring habitats that have smooth verticle sandstone
walls that angle inward. After a recharge event, tinajas offer a
source of water for many flora and fauna species, however, they can
become death traps for wildlife as the water level recedes. One of
the major efforts to improve water sources in the desert where
entrapment of wildlife has occurred is to modify tinajas to allow
animals to escape should they slip into water.

Also, a kind of algae grows in these tanks when they have water in
them. They lie dormant when it is dry, waiting for the next snow or
rain, whenever that will be. Don't always put your trust in a specific
tinaja occurring in a specified desert location. It would be wise to
carry with you a plentiful amount of drinking water, because the
desert can be a rather inhospitable place when it wants to be!

Photo taken in the Calico Tanks area, just west of Peak 4570' inside
Nevada's Red Rock Canyon Nat'l Conservation Area on March 16, 2008