12-05-2002 - Biodiversity

sagar: Author=’Jorge Salazar’ program=’3622′ video=”The native range (dark brown) and introduced range (red) of the flathead catfish. Image courtesy USGS._DB:_ This is Earth and Sky. The flathead catfish is a native of the Mississippi River drainage area in the U.S.

_JB:_ But it was introduced as a sportfish in the 1950s and 60s into coastal rivers of the southeastern U.S. And now the flathead has devestated many native fish species. Tom Kwak is a researcher at North Carolina State University. He’s part of a four-year project – now in its third year – to study the flathead catfish.

_Tom Kwak:_ First of all, just understanding a fish species is the most important thing that a management agency can do to begin managing it.

_DB:_ You might think of a catfish as sedentary. But in North Carolina – where flatheads are alien species – Kwak found that this fish can move 50 kilometers – about 30 miles – in just weeks.

_Tom Kwak:_ A primary message in the research is that we have to stop the spread of the species any further . . . The fish seems to be moving, probably helped out by people, to get into new rivers.

_JB:_ Anglers know about “catch and release” programs in some waters. But Kwak recommends that anglers who catch flathead catfish “harvest” them – or remove them – to keep them from doing more damage.

_DB:_ Thanks today to the “U.S. Forest Service”:http://www.fs.fed.us/ and to the “National Fish and Wildlife Foundation”:http://www.nfwf.org/ – supporting the conservation of native fish, wildlife, plants, and their habitats. We’re Block and Byrd for Earth and Sky.

Written by EarthSky