Changing Tides: Lake Michigan Could Best Support Lake Trout and Steelhead

Typography

Invasive mussels and less nutrients from tributaries have altered the Lake Michigan ecosystem making it more conducive to the stocking of lake trout and steelhead than Chinook salmon, according to a recent U.S. Geological Survey and Michigan State University study.

Reduced stocking of Chinook salmon, however, would still support a substantial population of this highly desirable recreational salmon species, which is a large contributor to the Great Lakes multi-billion-dollar recreational fishery.

“Findings from our study can help managers determine the most viable ways to enhance valuable recreational fisheries in Lake Michigan, especially when the open waters of the lake are declining in productivity,” said Yu-Chun Kao, an MSU post-doctoral scientist and the lead author of the report.

Invasive mussels and less nutrients from tributaries have altered the Lake Michigan ecosystem making it more conducive to the stocking of lake trout and steelhead than Chinook salmon, according to a recent U.S. Geological Survey and Michigan State University study.

Reduced stocking of Chinook salmon, however, would still support a substantial population of this highly desirable recreational salmon species, which is a large contributor to the Great Lakes multi-billion-dollar recreational fishery.

“Findings from our study can help managers determine the most viable ways to enhance valuable recreational fisheries in Lake Michigan, especially when the open waters of the lake are declining in productivity,” said Yu-Chun Kao, an MSU post-doctoral scientist and the lead author of the report.

Managers have reduced Lake Michigan stocking levels of Chinook salmon at least three times over the past decades in response to declining prey fish and the natural reproduction of Chinook salmon. For the new study, scientists investigated the lake’s current and future abilities to support different fish stocking efforts. They found that recent decreases in critical lake nutrients, partly due to increases in invasive species such as quagga mussels, reduce the amount of Chinook salmon that the lake can support. 

Read more at US Geological Survey

Photo: Chinook Salmon. Photograph courtesy of Michael Humling, U.S. Fish and Wildlife Service