Courtesy Photo Members of the U.S. Fish and Wildlife Service net sea lampreys from Thunder Bay last year are seen in this courtesy photo from the U.S. Fish and Wildlife. This year, an assessment is taking place at the Long Lake outlet.

ALPENA — A U.S. Fish and Wildlife assessment crew will conduct a sea lamprey assessment project at the Long Lake outlet in Alpena County from June 18 through June 27.

The study will help scientists get an estimate of the abundance of sea lampreys and use the collected data to determine if there is a need for population control operations.

According to Aaron Jubar, supervisor of fish biology at U.S. Fish and Wildlife, the Long Lake outlet that connects the inland lake with Lake Huron is a hotspot for the breeding and growth of the lampreys, which can have a negative impact on the local Great Lakes fishery.

Jubar said Fish and Wildlife crews will utilize electrofishing equipment to help count lamprey in shallow water and Granular Sea Lamprey Larvicide, a lampricide approved by the U.S. Environmental Protection Agency and Health Canada Pest Management Regulatory Agency, to coax the animals in deep water to the surface where they can be collected and counted.

Jubar said barriers keep the lampreys from entering Long Lake from the creek and outlet, and so far, no sea lampreys have been found in the inland lake.

U.S. Fish and Wildlife conduct a survey each summer to measure if treatment needs to be done to lower their numbers. Jubar said the last time a control measure was done at the Long Lake outlet was in 2021.

Jubar said controlling the population of the lampreys prevents damage to the fish and wildlife in local bodies of water.

“Sea lampreys invaded the Great Lakes during the 1920s and have been a permanent, destructive element of the fishery ever since,” he said. “Sea lampreys attach to fish with a suction cup mouth, rasp a hole through the fish’s scales and skin, and feed on blood and body fluids. The average sea lamprey will destroy up to 40 pounds of fish during its parasitic phase.”

If it is determined that control measures are needed, Jobar said a chemical is dispatched into the infested water to kill the larvae before they reach a size beyond four or five inches. He said the chemical, which does not impact humans, dissolves and dilutes in about 12 hours.

Jubar said the chemicals do have a slight impact on some local species of fish, but it is nothing that endangers the fish as much as the lampreys do. He said the limited threat to the health of the fishery is part of the reason why control treatments aren’t taken every year.

“We do a survey every year, but we try to only do control action every four or five years,” Jubar said.

Steve Schulwitz can be reached at 989-358-5689 or sschulwitz@thealpenanews.com. Follow him on Twitter @ss_alpenanews.com.