"There," she said, pointing a handheld antenna over the boat's gunwale. "The fish is right under us."

Station WAL-I was on the air.

Deep under the surface of Charles Fork Lake swam a walleye with a tiny transmitter attached to the base of its dorsal fin. Every second or so, the transmitter emitted a signal that, when detected by Phillips' receiver, created that telltale chirp.

Armed with this or similar technology, Division of Natural Resources biologists hope to track walleye movements in Southern West Virginia's New River. The work Phillips does is a yearlong test to see which equipment works best.

"This is part of our effort to reintroduce native-strain walleye to West Virginia waters," she explained. "We needed a way to effectively track the native-strain fish we've been stocking there for the past several years. We know they tend to move a lot, but we don't yet know where they go."

Phillips said information gathered during the walleye-tracking project would be shared with anglers to give them a better idea of where and how to fish for walleye, a species highly prized as table fare.

"It will also give us biologists an idea of where the fish go to spawn and where they go when they're not spawning," she added.

Until now, DNR crews had relied on capturing and recapturing tagged fish to determine the extent of their travels. It was a hit-or-miss proposition.

"In a river like the New, it's hard to count on recapturing a walleye you've tagged," Phillips said.

Earlier this year, Phillips tagged 12 walleyes with radios - four fish from Charles Fork Lake and eight from the New River. The fish from Charles Fork have been relatively easy to find in the 70-acre impoundment, but the fish in the New have been a bit more challenging.

"I tagged the eight New River walleyes during the spawning season," Phillips recalled. "All of them were captured in the big pool at Sandstone Falls. Within two or three weeks, all but three of them were gone. I later found one of them more than 20 miles downstream."

With the radio transmitters, Phillips doesn't have to recapture the fish. As long as she's within a quarter mile of them, and provided they aren't more than 30 feet below the surface, she'll pick up the signal.

"As I ride in the boat, I swing the antenna from side to side," she said. "The signal is strongest when the antenna points directly at the fish. We can use that directional signal to [hone] in on exactly where the fish are in the river."

So far, the transmitters Phillips is testing seem to be working well. Soon she'll start testing another system, one that combines radio tags with passive acoustic sensors.

DNR biologists are already using acoustic sensors to track muskellunge movements in Ritchie County's North Bend Lake. The sensors, which are anchored to the bottom of a body of water, pick up tiny sounds emitted by transmitters embedded in fishes' bodies every time the fish pass within range of the sensors.

The sensors log the contacts, and biologists periodically retrieve the sensors and download the accumulated data onto a laptop computer.

Phillips said the acoustic-radio combination, if it works as expected, would allow her to track New River walleyes much more efficiently.

"With the passive receivers, I can collect the data and have a good idea of what parts of the river the walleyes are in," she explained. "Then I can take a float trip down the river and track the fish with the radio."

The research is part of what Phillips calls a "big effort" to reestablish what once was a thriving New River walleye fishery. DNR officials are trying to replace the weakened, crossbred strain of walleye currently in the river with the more robust, pure strain native to the river.

"Once we know which system works best, we can go ahead and start tagging walleyes for study," Phillips said. "I'll be the one doing the research. I think it's important research because it benefits both the scientific community and anglers alike."

Reach John McCoy at johnmc...@wvgazette.com or 304-348-1231.