Bullfrog - Watchable Wildlife

Quick Facts

  • Bullfrogs are the largest frogs in North America.
  • After hatching they can remain as tadpoles for one to three or more years depending on conditions.
  • Male bullfrogs stake out and defend their territory from any male frog intruder.
  • Bullfrogs can jump up to 15 times their body length to catch anything from insects, crayfish, minnows, and other frogs (even other bullfrogs) to small rodents, hatchling turtles, ducklings, bats, and snakes!
  • During the winter, bullfrogs burrow into the mud on the pond bottom and remain there until spring, absorbing oxygen stored in the mud. Tadpoles may be active under the ice all winter.

What to Watch for

Size

Generally 3 ½ -6 inches with a maximum length of 8 inches.

Appearance

Adults: Green with mottled darker green, black, and brown with muscular hind legs. Males may have a yellow coloration on the throat during the breeding season. Females have a white throat. To distinguish between a bullfrog and a green frog see below.

Tadpole (Larvae): Bullet shaped with an olive-greenish color and a tail marked with small distinct black dots; lacking legs until shortly before metamorphosis.

Where to Watch

Along the banks, edges, and shallows of wetlands such as freshwater ponds and lakes, swamps, marshes, and slow moving streams and rivers. Bullfrogs are especially common where there are areas of emergent, submerged, or floating patches of plants that provide cover.

What to Listen for

Male bullfrogs make a loud deep distinctive call "jug-o-rum, jug-o-rum," by inflating a balloon-like sac in their throat. Calling peaks between early May and mid-July.

When to Watch

The best times to watch are from mid-March in southern parts of the state to mid-July in the north.

More Information About Bullfrogs

Bullfrog distribution map in NYS
Effects of PCBs (polychlorinated biphenyls) on bullfrog tadpoles and amphibians

The difference between a bullfrog and a green frog:

All frogs have a circle-shaped external hearing organ (eardrum) known as a tympanum located directly behind the eyes of the frog. A bullfrog has a ridge that runs from the back of the eye around the tympanum and then stops. On the green frog, this ridge extends beyond the tympanum down along the back of the frog. A bullfrog's call is deeper and longer. A green frog's call is high pitched and shorter. Lastly, bullfrogs are much larger than green frogs. An adult bullfrog is usually 3 ½ to 6 inches in length, while an adult green frog is usually only 2 ½ to 3 ½ inches in length.

The Best Places to See Bullfrogs

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