GRAND RAPIDS, Mich. – King Salmon are declining at an alarming rate according to biologists and the Department of Natural Resources.
“The salmon population first declined in the mid-eighties due to bacterial kidney disease which was a result of lower prey in the lake,” said Jay Wesley, Lake Michigan Basin Coordinator with the DNR.
And the Great Lakes food chain has been changing ever since, affecting the health of Michigan fisheries, local businesses, even the actual size of King Salmon. Chinook salmon, another name for the King Salmon, are known for their large size, some weighing around 30 pounds. Wesley said not only is the population decreasing, but so are the size of the fish, now weighing around 15 pounds.
“It’s a big issue because the lakes are changing,” Wesley said. “If you look lake-wide at the bio-mass of fish that were caught, specifically Chinook Salmon, we’re probably at about 5 million pounds caught each year.”
Now, we’re down to about two million salmon being caught each year according to Wesley. It’s a trickle effect that begins at a molecular level. Millions of invasive species like Quagga and Zebra Mussels cover the lake floor filtering valuable algae from the water. This eliminates vital plankton that feed wild prey fish such as Alewives which feed big game fish, particularly Chinook salmon.
“Because there’s less prey, the capacity to support the current Chinook salmon just isn’t there,” Wesley said. “So one way we can address that is to lower the Chinook stocking. That will help reduce predation pressure on the remaining prey.”
As for invasive mussels, biologists are hoping they’ll reach a peak, allowing algae and plankton back into the water. But for now, the declining population is causing problems here on land.
“And a lot of these towns rely on that business coming into town, to eat at the restaurants and stay at the hotels and take a trip out on the lake and do some fishing,” said Wesley. “Making sure we have a diverse fishery remaining out there so charter boats and folks that fish the pier have something to go after.”
Other game fish including Steelhead and Coho are doing well, Wesley said. The Michigan DNR's position is to push for diversity through stocking fish varieties.
