Landlocked sea lamprey are suspected of staying in the Cheboygan River system and feeding. Photo: Great Lakes Fisheries Commission.

By Howard Meyerson

CHEBOYGAN, MI – Researchers who are studying sea lampreys in the Cheboygan River system are looking for a little help from anglers over the next couple of years. Evidence is mounting that a landlocked population of lampreys exists in the Cheboygan River watershed, which includes the Maple, Sturgeon and Pigeon rivers, along with Burt and Mullet lakes.

Landlocked means the lampreys don’t migrate out to the Great Lakes to feed – in this case Lake Huron. Instead, they emerge from river bottoms where they live as larvae, make their way downstream during their metamorphosis to a blood-sucking parasite, and stop short of Lake Huron, feeding on fish Burt and Mullett lakes before eventually returning upstream to spawn and die.

Federal officials say that phenomenon not only has implications for sport fish that live in those waters, but for the agencies tasked with sea lamprey control. Until recent years it has been assumed that Cheboygan River lamprey migrate out to Lake Huron and return to spawn. The river system has been treated with lampricide for more than 50 years.

Now federal officials are considering other lamprey control options like sealing the Cheboygan dam and locks so lamprey cannot pass, then killing off any residual populations with chemical treatment. It is a move, they say, that could save a great deal of money for treatment, a cost estimated at $1.5 million every three years.

“Lampreys have traditionally lived in those streams and lakes,” said Nick Johnson, a research ecologist with the U.S. Geological Survey’s Hammond Bay Biological Station in Millersburg. “What’s new is they may be stopping for a snack in Burt and Mullet Lake(s) without going out to Lake Huron.

“We want to learn the size and location of the potential landlocked population. If anglers notify us of any (lamprey) wounds they find on steelhead, northern pike, and musky, and send us any lampreys they capture while out fishing, that will help give us more information.”

LAMPREY TRAPPING PLANNED

Lamprey control in the Cheboygan River watershed began in the 1960s, but state officials say it remains one of the biggest lamprey runs on the Great Lakes.

“There is 15,000 or more lamprey moving up the Cheboygan River every spring,” said Tim Cwalinski, a senior fish biologist from the DNR’s northern Lake Huron management unit. “They are attracted to those rivers because of the pheromones from juveniles that get released in the system.”

Photo: Courtesy of Great Lakes Fisheries Commission

Johnson plans to trap lamprey on the Maple, Pigeon and Sturgeon rivers this year and next, from April through July, looking to assess the population size and their genetic makeup. Spawning lampreys typically appear in late April or early May once the locks begin to operate. The 2-year netting study follows a 2013 pilot study funded by the Great Lakes Fisheries Commission that provided some evidence of a potential landlocked population.

“We found adult lamprey in the Maple River in early May before the locks opened,” Johnson said. “We found just a few – one in the Maple River, two in the Pigeon River and one in the Sturgeon River. They were smaller than average and have a different cartilage signature from those in Lake Huron, which suggests a different population.”

QUESTIONS ABOUT THEIR IMPACT

Cwalinski said their presence makes no difference to the fishery, though anglers have reported the occasional fish with a lamprey wound. The question of their presence has more bearing on what happens to the locks and dam in the future and whether federal agencies would be able to save money in treatment. The DNR, he said, prefers to not to see barriers to fish passage on rivers.

“Nothing has changed. The fishery hasn’t changed. In fact, we have seen a burgeoning population of steelhead,” Cwalinski said. “What we have said is we would be opposed to the cessation of fish passage genes up and down stream. If you take a lock and make it essentially a dam, it’s a dam.  When it comes time to talk about a new design, there is a lot who want to talk about it. But we’re not there yet.”

Marc Gaden said the study is important. He is a spokesman for the Great Lakes Fishery Commission.

“I view it as fact finding,” Gaden said. “We’re trying to find out what is going on. Have the lamprey expanded their range? If there is an expansion that could inflict damage to fish populations on Burt and Mullet Lake, we want to know.

“It’s one thing if it is a typical garden variety migration upstream, but if they spend their entire life in Mullet Lake and spawn in the tributaries and inflict damage, that is a different story.”

Anglers are being asked to contact Johnson if they find lamprey wounds on sport fish in the Cheboygan River system, and to turn in any lamprey they find. Johnson can be reached by email at njohnson@usgs.gov or by phone at: 989-734-4768, extension 128. Flyers posted at various boat launches detail how to send in a lamprey or observation. Observation coupons are available at bait and tackle shops in Indian River, Onaway and Petoskey.

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© 2014 Howard Meyerson

This story appears in Michigan Outdoor News.