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Amphibians of Washington

American bullfrog
(Lithobates catesbeianus)


What they look like

  • Largest frog in North America; 17-25cm with legs
  • Light to dark green or brown with or without spots
  • Eyes are golden in color and larger than their tympanums (eardrums)
  • Have a fold of skin on each side from their eye down along their sides
  • Legs have thick black stripes on their legs and have very large webbed feet

Where they live

  • They are an introduced species in Washington State, originally found only to the east of the Rocky Mountains
  • Currently found in many low elevation areas in Washington
  • Live in lakes, ponds and wetlands, generally in the water or on the shoreline


  • Breeding season is spring and summer
  • Females can lay up to 25,000 eggs in one mass
  • Eggs can hatch within 5 days but takes the tadpoles two years to complete metamorphosis

Cool Biology Facts

  • Can jump 3-6 feet! (1-2 meters)
  • Have been introduced worldwide and have caused problems in many areas due to competition with local species.
  • Males are territorial and will get in physical fights to defend their territory.
  • Many restaurants in the US have bullfrogs on the menu and there are actual bullfrog farms to supply them!
  • Have no natural enemies due to the toxicity of secretions from their paratoid glands.
  • Are often carriers of the chytrid fungus that has been one of the major reasons for many frog species declines; however they are generally resistant to the devastating effects of the fungus.


Distribution Map


Their population is increasing and in many areas efforts are being made to eradicate them.