Birds

• Small birds such as sparrows feed on insects.David De Lossy/Photodisc/Getty Images
  
  Smaller, insect-eating birds are at that the bottom of the desert-bird hierarchy, and may find themselves prey to larger birds. This encourages them to forage in flocks like the bushtits and black-throated sparrows. Most forage on the ground, including the mourning dove, spotted Towhee, and European starling. Larger, more aggressive birds like the American kestrel and northern mockingbird eat larger insects such as crickets and grasshoppers.
  
  

Scorpions

• The nocturnal scorpion hunts at night.Thomas Northcut/Digital Vision/Getty Images
  
  Not exclusive to the desert, scorpions slow their metabolism to survive in many harsh climates. These burrowing arthropods only have one major environmental requirement for their survival: soil. Over 90 species of scorpion reside in the deserts of the southwestern United States. They hunt at night, primarily feeding on insects but may also eat lizards and other small animals.
  
  

Lizards

• Large desert lizards such as the gila monster eat small mammals and birds.Jupiterimages/Photos.com/Getty Images
  
  Cold-blooded desert lizards are generally rather small, from six to ten centimeters in length, with coloring that helps them blend into their desert surroundings. These small lizards move very fast when necessary. Some common insect-eating desert lizards include the banded gecko, spiny lizard and horned lizard. Some larger lizards, like the chuckwalla and iguana, eat plants.
  
  

Spiders

• Tarantulas eat beetles and other large insects.Jupiterimages/Photos.com/Getty Images
  
  Desert spiders prey on desert insects, but a lack of trees makes webs less useful. Most forage on the ground at night, attacking fast and using venom to paralyze their prey. Common desert spiders include the wolf spider, funnelweb spider and brown recluse. One large spider, the tarantula, will eat anything it can manage; but it generally dines on grasshoppers, beetles and other large insects.