The Great Lakes
The Great Lakes are undergoing “an ecological catastrophe unlike any this continent has seen,” according to Pulitzer Prize finalist Dan Egan. Humans have dramatically altered the lakes’ fauna since invasive species first snuck up through the man-made Saint Lawrence Seaway. Blunders sometimes stemmed from well-meaning policies. Researchers imported Asian carp to kill river nuisances without chemicals, and now some worry the fish has silently invaded Lake Michigan’s floor via the Chicago Sanitary and Ship Canal. And the lakes’ imported problems are quickly becoming national disasters, such as the tiny and quick-spawning quagga mussel that has infested regions as far away as Lake Mead and Lake Powell on the Colorado River.