Monitoring Rivers Rougher

From June 14, 1991 (update #8)

LOUISVILLE, Ky. -- Zebra mussel veliger monitoring in large river systems presents difficulties not faced in lake systems, according to James H. Thorp, aquatic ecologist at the University of Louisville. Thorp has collected plankton samples as part of a search for zebra mussel veligers since January from three pools of the Ohio River, ranging from Cincinnati, Ohio, to 70 miles west of Louisville. He reports that equipment suitable for lake plankton sampling is not strong enough to stand up to the strong currents and large sediment loads present in large river environments. Thorp found that a standard Schindler-Patalas trap continually broke down under Ohio River sampling conditions. Standard plankton nets also didn't last long when pulled vertically through the river water. He was able to continue to use plankton nets with a modified technique and reports resorting to using "high tech buckets" to sustain his sampling program. Thorp believes that the zebra mussels now in North America originated from populations found in European rivers, and he expects zebra mussels will also be successful in North American rivers. Thorp is interested in hearing from others who might be sampling large river systems for zebra mussels; he can be reached at (502) 588-6731.

ID: 19910614-8.

The Zebra Mussel Update was a 4- to 8-page quarterly national newsletter published by the University of Wisconsin Sea Grant Institute from May 1990 through May 1997. The ZMU documented the spread of the zebra mussel -- an exotic nuisance mussel -- through North America's freshwater environments, especially the Great Lakes, and on efforts to control it.