Lithobates catesbeianus

Identification Tips:

• Largest frog in North America (to 20 cm excluding legs)
• Eardrum as large or larger than the eye
• No ridges along sides of back
• Prominent fold extends from rear of each eye to top of foreleg, wrapping closely around the eardrum
• Webbing on hind feet extends to end all but one toe
• Throat yellow in breeding season

• Large size (some >10 cm)
• Well defined but very small black spots on upper half of tail and head
• Belly often yellowish, especially on larger individuals

Egg Masses
• Eggs black above, whitish below, in flat gelatinous masses that may exceed 1 m in diameter

Conservation Status:

British ColumbiaCanadaNatureserve
COSEWICSpecies at Risk Act
Introduced SpeciesNot AssessedNoneG5

Life History:

• Breeds in mid-summer; late June to July in Fraser Valley
• Reach sexual maturity several years after metamorphosis
• May migrate seasonally between habitats several kilometres apart
• Adults eat a variety of invertebrates and small vertebrates; anything that can be captured and swallowed.
• Tadpoles eat algae, plants, organic debris and very small invertebrates.
• Overwinter at the bottom of pools or under cover in or near water.


• Ponds, swamps, warm lakes
• Tolerate brackish water
• Tadpoles overwinter at least once


British Columbia
• Fraser Valley and southern Vancouver Island

• Native to eastern North America from Nova Scotia West through Great Lakes and south through central and eastern United States to northeastern Mexico
• Introduced feral populations in Western North America, Carribean Islands, Europe, Britain, Hawaii and Japan


• Bad news: Implicated in the extinction of numerous native fish and amphibians from the many areas to which it has been introduced.

Primary Information Sources:
 Efauna BC:
 BC Conservation Data Centre: