Heat boils streams, killing thousands of fish

As the blistering heat wave and drought continue, tens of thousands of fish are dying in the Midwest as their rivers dry up and water temperatures rise to almost 100 degrees Fahrenheit.

In Iowa last week, the waters reached 97 degrees, killing about 40,000 shovelnose sturgeon. Officials in Nebraska say thousands of catfish, sturgeon, carp and other species in the Lower Platte River have turned up dead. And in Illinois, tens of thousands of large and smallmouth bass and channel catfish have died. At one lake in the region, the dead fish clammed up a power plant's intake screen, causing it to shut down a generator.

"It's something I've never seen in my career, and I've been here for more than 17 years," said Mark Flammang, fisheries biologist with the Iowa State Department of Natural Resources. "I think what we're mainly dealing with here are the extremely low flows and this unparalleled heat."

The heat is also threatening endangered species in both Illinois and Iowa. Almost two-thirds of the lower 48 states are in drought, and more than half of the country's counties have been declared natural disaster areas.