Invading Bullfrogs Nearly Unstoppable

The North American bullfrog population is booming. That may sound like good news, but it isn’t–not when the frog has leaped far beyond its native habitat.

“They are one of the most successful amphibians in the world, and they are causing trouble in several countries,” said Cecil Schwalbe, a biologist with the U.S. Geological Survey at the University of Arizona in Tucson.