Lake Mille Lacs is Minnesota's own Rubik's Cube: a walleye fishery puzzle that seems impossible to solve.
The complexity came to a head this fall when the Department of Natural Resource's gill-net surveys showed a declining number of male walleyes in the big lake, as well as a drop in the overall walleye population to the lowest levels in 40 years. And the lake's larger walleyes are getting skinny, a sign they are not finding enough food.
Think you have the answer? Before you say yes, consider:
The walleye fishery is co-managed to serve thousands of sports anglers, local fishing and tourism-related businesses and Chippewa tribes, who net fish each spring.
Sharing the walleye harvest means regulations for sports anglers that require them to release larger fish, altering the composition of the fishery.
The bands' nets, too, tend to target smaller walleyes.
Smallmouth bass have become much more abundant, as have northerns, changing the dynamics of the fishery and potentially impacting the forage base.
The invading zebra mussel population has exploded, causing unknown effects.