Hudson is Cleaner, But Fewer Fish

The Hudson River is a lot cleaner than it was in 1975, but the number of fish swimming in it is much lower.

That's the finding of a new study by the group Riverkeeper.

Dr. Peter Henderson is one of the study's authors.

HENDERSON: In decline we have whitecap fish, weekfish, rainbow smelt, American shad, white perch, and less common but still quite important is the American eel.”

REPORTER: The report suggested a variety of causes for the fish decline including global warming and the invasion of the zebra mussel. It also blamed the five river-side power plants that take in billions of gallons of water each day as a coolant -- along with countless doomed fish.

One bit of good news: striped bass has rebounded strongly, after limits were placed on the number that can be caught.