DNR management of Mille Lacs walleye questioned
September 21, 2017
Paul Radomski, Minnesota DNR Ecological and Water Resources research biologist is challenging basic assumptions behind DNR management of the Mille Lacs walleye fishery.
Radomski presents his research as “Personal observations on the management of the Mille Lacs walleye fishery.” In it he provides a much different view of DNR’s co-management of Mille Lacs walleye fishery.
Radomski’s August 25, 2017 report tries to answer two questions:
What aspects of Mille Lacs fisheries management need improvement?
What factors were important in the reduction of the walleye population?
- The Mille Lacs fisheries management goal of protecting large walleye has suppressed young walleye survival and reduced walleye productivity.
- The current Mille Lacs walleye spawning stock biomass is plentiful and the population can produce ample walleye eggs and very large numbers of young walleye.
- The walleye populations has not collapsed, weakened, or failed; however, the management system has struggled. Suggestions are provided on how to improve the system.
Key points include the following:
- Recent walleye quotas were set assuming that spawning stock biomass was at or near critically low levels. This assumption is incorrect. The current Mille Lacs walleye spawning stock biomass is plentiful and the population can produce ample walleye eggs and very large numbers of young walleye.
- The management goal of protecting large fish has suppressed young walleye survival and reduced walleye productivity.
- Therefore, a benchmark that is used to influence quota setting and close the Mille Lacs walleye fishery appears arbitrary.
- The Mille Lacs walleye population has not collapsed, weakened, or failed, nor does it need to be rebuilt; however, the management system has struggled.
- Meeting a quota with hard edges and undue protection of large fish is not likely in the best interest of a tribal or sport angler fishery.
- The management system could be simpler. It could be more pragmatic on the difficulties of estimating the number of walleye in the lake with enough accuracy for a hard-edged quota.
- Strong year classes are more likely when spawning stock biomass is of moderate abundance rather than at high abundance.
- Therefore, it is reasonable lo conclude that a policy of continual stockpiling and maintenance of high spawning stock biomass was the most likely factor in the lower Mille Lacs walleye population.