Bullfrogs Causing Ecological Disaster in Arizona

It may seem strange to those of us who grew up catching, gigging and eating them, but the common bullfrog is at the forefront of an impending ecological disaster in Arizona.

From this story in the Arizona Republic:
At night on the Buenos Aires National Wildlife Refuge southwest of Tucson, a low, insistent bellow drowns out the chaotic insect symphony under way along the edge of small ponds. At times, it's a solo, at others a raspy chorus. Bullfrogs own this pond. All other aquatic creatures take notice and don't make any long-term plans.

But this is not the natural soundtrack for a pond in the southern Arizona desert. Bullfrogs are not native to these waters, and they do not play well with the local fauna. At 8 inches long, or longer, they eat smaller native frogs, fish and snakes, among other things, and have wiped out communities of Chiricahua leopard frogs and northern Mexican garter snakes. Arizona is losing its native wildlife in part because non-native species are thriving on landscapes that have been altered by development, water loss and climate change.

Too often when we think of invasive non-native species we think of exotics like Asian carp or snakeheads or pythons, but many species native to one part of our own country can and do become a management nightmare when introduced outside its traditional range or it begins expanding on its own. What's the worst "native non-native species" in your area?