American bullfrogs, which were once confined to much of eastern North America, have exploded around the world with dire consequences for native species. Now researchers say they may have found a way ...

American bullfrog DNA has turned up not far from the only known habitat of Pithecopus rusticus — a small, critically endangered tree frog that lives in Brazil. These neon green, orange and black frogs ...

Sidney Woodruff of UC Davis holds a northwestern pond turtle at a field site in Yosemite. (Courtesy Sidney Woodruff) The call of American bullfrogs was deafening when scientists from the University of ...