A University of Connecticut team of researchers is using electricity to find some fish.

The herring is a small fish that used to thrive in the Connecticut River, but now seems to be disappearing.

Channel 3 Eyewitness News reporter Dan Kain joined the researchers for a night as the boat went into the river at dusk. By nightfall, the crew used electricity to zap the water and catch herring, striped bass and other fish.

"We pump about 600 volts into the water. That temporarily immobilizes the fish so we can net them up to the boat with big long nets, bring them into the boat, collect all the information we need and then we can release them and they swim away unharmed, probably a little bit confused, but they are unharmed," said Justin Davis, a University of Connecticut Ecology and Evolutionary Biology doctoral student.

In addition to noting age, size and weight, the researchers also check the fish to determine what they've been eating. One theory holds that the bass are eating the herring, but science isn't simple.

"It's a plausible explanation based on the facts. We have a very viable hypothesis, but we need to go out and find out exactly what's happening, get the hard facts and see what that tells us about the hypothesis," Davis said.

On a good night, the researchers can catch as many as 150 striped bass, both large and small, and about 300 or 400 herring.

"These guys, they're absolute pros. They are really, really good," Davis said.

The bass are also tagged to see where they go when they leave Connecticut. Some have been found as far north as Cape Cod and as far south as the Carolinas.

The three-year project comprises part of Davis' doctoral dissertation.

"I've been working on this for five years and I've been thinking about nothing but river herring for large portions of my life, which I think is normal, but others might think is a little weird," Davis said.

He added, "This is the fun part of being a fisheries biologist. We really enjoy this time we get to spend on the water."

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