And the population of lake herring, once the most abundant fish in the lake, has been reduced to extremely low levels, according to researchers.
As has been reported by the U.S. Geological Survey for the last several years, the prey fish biomass in Lake Michigan is at record low levels, largely due to the food and energy filtering impacts of invasive quagga mussels.
The population of alewife, the invasive fish that became the primary forage fish in the lake after the decline of the ciscos, is the lowest seen since bottom trawl studies were initiated in the 1970s.
The current state of Lake Michigan presents a challenge and, some think, an opportunity.
What can be done to build the fishery?
There is no appetite among state or federal agencies to stock alewife, an invasive species.
But a proposal is afloat to restore lake herring in Lake Michigan.
Chuck Bronte of the U.S. Fish and Wildlife Service presented an update on the idea in early December at a meeting of the Wisconsin Federation of Great Lakes Sport Fishing Clubs.
The concept of lake herring restoration began taking shape in 2013 with the formation of a task group.
Bronte said Great Lakes fishery managers had expressed interest in reestablishing a native forage base consisting of various forms and species of ciscos.