American Bullfrog (Lithobates catesbeianus)

  • Largest frog in Wyoming (may be introduced)
  • Size: ~2 inches (metamorph) to ~6 inches (adult)
  • Dorsal color: light green to dark olive or brown
  • Dark spots or dark mottling
  • Ventral color: cream to yellow with dark mottling
  • Dorsolateral folds end behind the tympanum (not continued down back)
  • Mp3 of call (courtesy of Gary Nafis,; contact Gary for permission to use on other websites)

Photo to right:

Eggs & Tadpoles

  • Eggs in large floating sheet on surface (1 to 5 feet wide with up to 20,000 eggs
  • Tadpoles olive green above with gold metallic flecks and lots of small dark spots on body, tail muscle and tail fin; cream to yellow bellies
  • Tadpoles can reach up to 5.5 inches
  • Tadpoles eyes are medial, anal vent is on the side

Bullfrog_eggmass_WGFD.jpg   bullfrog_tadpole_WGFD.jpg

Photos above: Wyoming Game and Fish Department

Breeding Habitat

Shallow portions of permanent water bodies with lots of vegetation; prefer warm water.


Photo by Wyoming Natural Diversity Database

Native Range

Bullfrog.jpgMap by Wyoming Natural Diversity Database