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Invisible Wildlife

The desert appears deserted at noon. Except for a few lizards
and the pink flash of a western coachwhip snake, nothing
moves across ground that can reach temperatures of 150o F.

The apparent emptiness reflects biological adaptations. To
the patient observer, this scene can reveal animals specially
attuned to desert extremes. The jackrabbit in the shade of a
creosotebush, the cangaroo rat deep in its burrow, the mule
deer hidden in an arroyo, are all merely waiting for evening's
cooler temperatures.

Kangaroo rats have deep burrows with a year-round
relative humidity between 30 and 50 percent.

Jackrabbits' large, translucent ears function like
radiators, dissapating body heat through a rich
network of blood vessels.

Coyotes search for roadkills, hunt a variety of
rodents, and even browse on plants.

You are most likely to spot the collared peccary, or
javeline, in early morning or late evening. Look for
evidence of chewed pricklypear.

The red racer or western coachwhip can tolerate
temperatures up to 100oF. Most other snakes are

Don't miss the rest of our virtual tour of Big Bend National Park in 1083 images.