The 21st Show

Dolphin Sounds in the Mississippi River in Illinois


University of Illinois

Bighead carp, black carp, grass carp and silver carp — these fish are all nonnative to U.S. waterways but, since the 1970s have been starting to appear here. They’re considered invasive because they compete with native species and can destroy habitats. Scientists are working to keep these carp out of the Great Lakes.

To tell us more about the new acoustic deterrent system, The 21st was joined by a USGS Scientist and the lead of the Bioacoustics team with the U.S. Army Corps of Engineers.


Marybeth Bray, USGS scientist 

Christa Woodley, Bioacoustics team lead with the U.S. Army Corps of Engineers


Prepared for web by Zainab Qureshi

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