(Forest Preserve District of DuPage County)

A west suburban forest preserve is dispatching an army of freshwater mussels to clean up contaminated waters. “They may be small, but they have enormous beneficial effects on the lives of other organisms,” said one staff member.

A hefty Bighead carp, one of several types of Asian carp, caught in a net near Morris, Illinois. (Evan Garcia / Chicago Tonight)

Wildlife agencies and fishermen in Illinois are using a Chinese technique to catch Asian carp, an invasive fish species threatening the Great Lakes ecosystem.

Scientists have found female eggs growing in the testicular tissue of some male largemouth bass taken from the Des Plaines River. (Jonathunder / Wikimedia Commons)

We speak to the co-author of a newly published study in which scientists dissected 51 male largemouth bass and found that 21 – some 41 percent – had grown female eggs in their testicular tissue.