Joshua Tree National Park

Joshua Tree National Park

Species Spotlight: Chuckwalla

March 9, 2012, 11:05 am

One thing you can almost always count on finding in the desert (besides an arid climate) is a lizard. Cold-blooded lizards are made for the hot temperatures and blazing sun. The unique chuckwalla is no exception. Chuckwallas, or “chucks” for short, are close relatives of the iguana. Growing up to 18 inches long, chuckwallas are the second largest lizard in the United States after the Gila Monster.

Endemic in the southwest deserts of the United States and northern Mexico, chuckwallas inhabit rocky terrain and lava flows of the Great Basin, Mojave and Sonoran Deserts. You’ll most likely spot these lizards in the wild at Joshua Tree or Death Valley National Parks. But you won’t see them for long; chucks are shy and will quickly flee to hide in between rocks. Chuckwallas protect themselves by crawling into rocky crevices. Then they inflate their body with air, blowing up like a balloon, to wedge even tighter between rocks, making it extremely difficult for predators, such as coyotes or birds of prey, to extract them.

Chuckwallas are best known for their distinctive coloring. Colors vary by age, sex and climate. Adult males have bright orange, white or yellow backs and tails with dark heads and limbs. Adult females are usually a grayish-brown color. Young chuckwallas are “banded,” which looks like stripes, of dark and bright colors.

Besides coloration, chuckwallas have large, flattened bodies covered in small spiny scales with loose skin around the neck and sides. Sharp claws help them grip rocks. Their diet consists mainly of leafy greens, fruits, flowers and occasionally insects.

Female hibernation lasts from around October until March. A female will lay between five and 16 eggs in the summer. Sometimes a female will only lay eggs every couple of years.

These colorful creatures are currently listed as a Federal Special Concern Species (FSC) because their habitat is threatened in active desert communities. However, they thrive in untouched desert areas.

Fun Facts:

-Chuckwallas sneeze salt! Because of their salty plant diet, chuckwallas have special glands behind their nose that harvest excess salt. To remove the build up, they sneeze.

- Once they hatch, chucks will stay in the egg for up to 24 hours before crawling out and exploring the world.

-Their tail will regenerate if it detaches.

-The name Chuckwalla stems from the Shoshone word “tcaxxwal” or “caxwal”

Photo: Chuckwalla photographed at Pinnacle Peak park in Scottsdale Arizona; Wikimedia Commons.