HOUGHTON – Marine biologists know a few things about coaster brook trout, mostly about where they spawn and where they die, but the day-to-day life cycles and migrations of the coasters, like most fish, are still relatively mysterious.

Michigan Tech doctoral student Chris Adams hopes to change that, with a new radio-tracking technique using microchips to tag fish and radio beacons across rivers that can log fish individually and record the dat

“You use the same type of chip you put on a cat or dog, and hoops that log fish when they go by,” he told members and guests at the March 15 Copper Country Trout Unlimited meeting, gathered at Michigan Tech’s Great Lakes Research Center.

“Handling is not really good for fish,” he noted of traditional catch-and-count methods. “You have to worry about mortality. With this we can track them, basically for the rest of their life.”

Adams said his work would originally focus on the coasters. He hoped to learn where they hung out when they weren’t being born or dying, where ‘cryptic populations’ of just a few fish indicated the possibility of coaster restoration, any instances of competition between the native and depleted coasters and the introduced and now-dominant salmon, and informing fishing regulations

“We’re applying now to look at whether one, 20-inch fish regulation might be working,” he said.

Other early efforts are helping to determine what size or age of fish survive their migration successfully, he said, and what conditions for migration are helpful or detrimental.

Tech Professor Casey Hutchins, who is leading Tech work on coaster ecology and restoration, said his group hopes to restore now-rare coaster populations, largely through ecosystem restoration. At one time, he said, the coaster was the dominant regional fish that migrated between streams and open Lake Superior.

After historical overfishing, their niche has been supplanted by salmon, rainbow trout and brown trout, he said.

The coaster is not generally considered an actual species, Hutchins noted. It’s actually a type of brook trout, though it can grow to twice the size of the normal variety – which never migrates out their streams – because of better nutritional opportunities.

The initial work locally has been at the Pilgrim River, Adams said, which enters Portage Lake just west of Houghton at the Nara Nature Preserve.

“I have a wire across the Pilgrim, and have tracked fish migrating as much as 6 kilometers there,” he said. His next project will be to install antennas at eight other local rivers, and he’s also working with a Northern Michigan University professor on an antenna that can be attached to a buoy in open Lake Superior water.

Once deployed, Adams said, existing antennas could be used to monitor other fish species as long as batteries and maintenance were taken care of, extending understanding of more of the undersea ecosystem.

“Once you have the equipment out there, tagging fish is pretty cheap,” he said.