Lake Michigan trout making comeback
South Bend Tribune
Published December 28th, 2006
MUSKEGON, Mich. (AP) -- A half-century after once-plentiful lake trout disappeared from Lake Michigan, the fish appears to be making a comeback.
Scientists recently discovered evidence that lake trout are reproducing on their own on a deep water reef in the middle of the lake.
The finding was significant because the fish has not reproduced on its own in Lake Michigan since the 1950s, when sea lamprey decimated the species.
"This is like finding a needle in a haystack," Jim Dexter, Lake Michigan basin coordinator for the Michigan Department of Natural Resources, told The Muskegon Chronicle for a story Tuesday. "This is definitely good news, but does it mean we're on the road to rehabilitating the lake trout population? No."
Lake trout are far from being out of danger in Lake Michigan. Scientists who discovered lake trout eggs hatching on a reef 30 miles offshore from Grand Haven found no evidence that the fish were living long enough to become juveniles or mature fish.
Until lake trout can reproduce on their own and reach maturity, the species will not be considered on the road to recovery, Dexter said. That has not happened in 50 years, since sea lamprey killed the last of the lake trout. Lamprey entered the Great Lakes decades earlier through the Welland Canal, which links Lake Ontario and Lake Erie.
The elimination of lake trout allowed alewife, another invasive species, to proliferate and take over Lake Michigan. By the early 1960s, alewife accounted for 90 percent of the entire mass of living organisms in Lake Michigan, and huge piles of dead, stinky alewives often rendered beaches unfit for human use.
DNR began stocking salmon in Lake Michigan in 1966 to reduce the number of alewife and create a new fishery to replace lake trout.
Government agencies have continued to stock lake trout in Lake Michigan for the past 40 years, planting about 2 million of the fish in the lake last year alone. But unlike salmon, which reproduce naturally in rivers that flow into Lake Michigan, lake trout have failed to recover.
By 2035, government fish biologists want 75 percent of all lake trout under 10 years old in Lake Michigan to be the result of natural reproduction.