Natural Area Preservation


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Rana catesbiana

Identifying Features

  • Locally common, has been declining in many areas.
  • Areas with abundant submerged and emergent vegetation are preferred. 
  • Rarely use temporary waters.
  • Tadpoles and adults bury themselves in bottom mud during hibernation.
  • Adults may hibernate from mid-October to April or May.
  • Love warmer weather, inactive until water temperature is above 60 degrees Fahrenheit.


  • Series of bass notes, like “jug-o-rum.”


  • Breeding usually begins in mid-May, peaks in June, and lasts into July
  • Territorial (6-20ft. in diameter).
  • 5,000-20,000 eggs are laid in a large free-floating mass.


  • Hatch in 3-6 days.
  • May transform in 2 years, but many take up to 3 years.
  • Sexual maturity is 2-4 years after transformation.

Conservation Note

  • Lakeside residential developments often lead to removal of shoreline and submerged vegetation, and heavy recreational use disrupts Bullfrog reproductive activities.
  • Heavily collected for restaurant and biological supply.
  • Unlikely that this species can survive intense exploitation for commercial or even personal use due to the extended time needed for development, maturation, and slow population replacement rate.

Habitat Type

  • Ephemeral wetlands.
  • Permanent wetlands.
  • Forests.
  • Grasslands and savannas.
  • To a lesser extent, bullfrogs may be found in urban and agricultural areas.

​​​​Natural Area Preservation
3875 E. Huron River Dr.
Ann Arbor, MI 48104

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Remy Long​
  Deputy Manager
Tina Stephens
  Volunteer & Outreach Coordinator
Becky Hand
  Stewardship Specialist
Michael Hahn
  Stewardship Specialist