Bullfrog - Rana catesbeiana

• Diagnostic Features:
  • Size: 3.5 to 8 inches (85 to 200 mm)
  • Color:
    • Plain green or with gray net-like pattern on green ground color
  • Other:
    • Our Largest frog
    • Prominent tympanum
    • Ventral surfaces white and mottled with gray or yellow
    • Dorsolateral folds end near tympanum
    • Long hind legs may be blotched or banded
    • Fully webbed hind feet, except fourth toe
  • Sexual Dimorphism:
    • Males are smaller than females
    • Males have larger tympanum
    • Males have a yellow throat
• Natural History:
  • Habitat:
    • This frog prefers large bodies of water, ponds, lakes, and slow streams.
    • It is most often seen at the edge of the water in vegetation or debris.
  • Behavior:
    • It is active in the evening and at night.
    • It is solitary and territorial.
    • It is able to leap great distances.
    • It feeds on anything that moves and can be swallowed, including insects, crawfish, small fish, frogs, birds and snakes.
    • If "cornered" it may flatten against the ground
  • Breeding:
    • Breeding takes place from February to October.
    • Egg masses are laid in a film on surface of the water.
    • Each female lays about 12,000 eggs
• Voice: Sonogram : Call (Lowndes, Wilkes, Appling, Jeff Davis, & Walker Counties ) Green Frogs in background.
  • Series of deep notes, which may sound like "jug o' rum"
  • Single, internal vocal sac
• Tadpoles:
  • Size: Some tadpoles reach very large size ~125 - 150 mm
  • Metamorphosis takes about a year
  • LTRF 1/3, 2/3 (most commonly) or 3/3;
  • 
  • tadpole larger, 25-140 TL; dorsum, dorsal fin and dorsal part of tail muscle with many, small, black dots with discrete borders, visible in live or preserved animals, but are faint (visible at magnification) when first form at about 20-25 TL; ground color brownish to greenish in life, brownish to gray in preservative; belly opaque white in larger specimens, sometimes tinged with yellow in life; body not strongly depressed and dorsal fin with notable arch; native and introduced ranges include most of continent; breeds in summer in larger lotic and lentic sites, may over-winter 0-3 years

    

  • low contrast (sometimes not noticeable without magnification) yellow band at mid-body; rest of body with scattered iridophores that appear to reside in various integumentary and subintegumentary layers; black pigment along blood vessel that parallels dorsal surface of tail muscle; fins clear and not marked; tail muscle unicolored or graded from dark dorsally to light ventrally; throughout continent in native and introduced ranges, breeds in summer depending on latitude, in larger lotic and lentic sites

    

  • tadpole larger, 25-140 TL; body dorsum uniformly olive to bright green in life, gray to brownish in preservative; dorsal fin and dorsal half of tail muscle totally lacking black dots of typical R. catesbeiana; belly densely white to bright yellow; body not strongly depressed and dorsal fin with notable arch; unusual color morphotype that breeds in summer in lentic and slow-flowing lotic sites in southern Alabama and Florida peninsula to at least Tampa Bay area
• Range:
  • In North America, this frog is found in the eastern two-thirds of the United States, barely extending into Canada and Mexico. Also introduced in some western states.
  • In Georgia, it is found throughout the state.

    

  • In Light Blue: Williamson, Gerald K. & Moulis, Robert A., Distribution of Amphibians and Reptiles in Georgia, Special Publication No. 3, Savannah Science Museum, Inc. Savannah, Georgia, 1994
  • In Green: Sound Recordings
  • In Yellow: From Both '94 study and Sound Recordings
  • In Magenta: Photograph, not found by '94, may or may not be sound record
  • In Medium Blue: Photograph and in '94 study, may or may not be sound record 
  • In Orange: County Record by other Herp Atlas Volunteers
  • In Red: US Distribution from various sources

May 25, 2008 - wwknapp@mindspring.com