By Howard Meyerson
ROGERS CITY, MI – Five years into a 6-year experiment to determine whether the Lake Huron brown trout fishery can be restored – by stocking the lake with large hatchery-raised yearlings – state fisheries managers have concluded it’s time to cut bait.
“It isn’t working,” said Todd Grischke, Lake Huron basin coordinator for the Michigan DNR. “We will not be moving forward with the fall-yearling program in the future.”
Support for that conclusion was nearly unanimous among members of the state’s Lake Huron Citizens Advisory Committee, a group of anglers convened by the DNR, which was presented with the study findings in June.
“It’s always hard to say it doesn’t work; let’s move on,” said Frank Krist, an angler from Rogers City and the committee chairman. “But people could see it wasn’t working. It’s better that we look to other areas and see how that hatchery space might be used.”
More than a decade of trying
That conclusion brings to a close more than a decade of efforts to improve the Lake Huron brown trout fishery. Various attempts compared strains of brown trout, stocking locations, and age-classes and sizes.
The most recent study began in 2009, the first of three years where 85,000 fall yearlings were stocked, followed by three evaluation years looking at angler catches.
The findings have some fisheries managers considering the role of alewives in a different light. Abundant alewife populations typically have been thought of as providing more food for salmon and brown trout. But researchers now are considering the possibility that they may have provided a food buffer instead, one that prevented young brown trout from being eaten by predator species like walleyes and chinook salmon.
“At one point we questioned whether it was the strain of brown trout we were planting, or something else,” Grischke said. “But we are now convinced it is not the strain. It’s the environment.
“When there are no alewives, anything stocked in a location like Thunder Bay, which is full of predators, doesn’t stand a chance. Browns are not migratory. They hang around with other salmonids and walleye and they are getting eaten.”
Brown trout fishery strong in 1990s
The Lake Huron brown trout fishery was strongest in the 1990s when alewife populations also were strong. State records show anglers reported catching 14,000 to 15,000 brown trout each year. But the fishery collapsed by 2004, and anglers that year reported only catching 2,000. The decline corresponded with the collapse of the chinook salmon population due to a drastic decline in alewives.
State fish managers were prodded by area anglers, who wanted them to fix things. They decided to attempt planting much larger browns, thinking their size would give them an advantage. Emerald shiner populations had grown and were healthy, and fisheries managers thought they could provide food for the brown trout. Fall yearlings were stocked. They were 14 months old and 10 inches long, “large, basically catchable fish,” according to Grischke.
They also were expensive, costing $2 to $3 per fish compared with stocked chinook salmon at 20 cents each. The study goal was a 5-percent return to the creel. But the results in the first and second evaluation years were far smaller.
“We are talking 1 to 2 percent,” Grischke said. “We had anticipated that by stocking larger fish that we would see very high survival. But we didn’t even come close. That’s why everyone was in agreement with stopping.
“We will do the last year of evaluation next year, but we won’t be looking to collect brown trout eggs this fall.”
Krist said he is disappointed that the experiment didn’t work. But he’s optimistic about the growth potential in the Atlantic salmon fishery.
© 2013 Howard Meyerson
This story appears in Michigan Outdooor News