American Bullfrog
For many the the low, throaty evening croak of an American bullfrog signifies summertime. However, in certain areas of the western United States, these big and mobile omnivores have recently become invaders of rivers, wetlands, and ponds.
USGS researchers in Montana are studying the rapid extent of bullfrog spread, as well as their preferred habitat along the Yellowstone River near Billings, Montana. The consensus is that this invasive species is now thriving and rapidly spreading in the Yellowstone River.
Bullfrogs are thought to be a cause in the declines of multiple amphibian and reptile species around the globe. They have a voracious appetite, the ability to reproduce rapidly, and are carriers of amphibian diseases. This makes them an extremely successful invader and a threat to biodiversity. Original public domain image from Flickr