Sternberg’s “common sense” report. . .
Questioning treaty management and calling for change

By Joe Fellegy

Dick Sternberg, well-known outdoor writer with a fisheries science background, came on board several months ago as the Landowners’ biologist/consultant. Dick reviewed DNR Mille Lacs fishery data and relevant scientific literature. He familiarized himself with treaty fisheries management, especially as it pertains to Mille Lacs. And then he prepared a 27-page report entitled, “Treaty Management: Threat to the Mille Lacs Lake Sport Fishery.”

The objective of Sternberg’s report is “to closely examine the present treaty management system, identify its weaknesses, and suggest a common-sense management solution that will not only maintain a healthy walleye population but also satisfy the Court and protect the interests of sport anglers and Band members.”

The unique court-approved treaty fisheries management process caps the combined Mille Lacs sport and tribal fisheries with a 24 percent exploitation rate ceiling on adult walleyes (12 inches and longer). That 24 percent is important, since it helps determine the annual “safe harvest level” or “quota” (in thousands of pounds). Sternberg joins other skeptics with his observations and questions, including “24 percent of WHAT?”

Sternberg maintains that given their present fish population sampling methods, including the annual fall gill net survey, DNR fisheries managers cannot really know how many pounds of walleyes are in Mille Lacs. And if that all-important “number” is shaky, well, so are the many things tied to it—including the annual quota for sport anglers and the strict regulations to keep them under that quota.

The 2002 safe harvest level for the combined sport and tribal walleye fisheries is 400,000 pounds. The tribal side, as part of its new five-year plan, is allocated 100,000 pounds this year. (This tribal allocation is guaranteed and does not have to adjust to ups, downs, and changes in the fish population unless it approaches 50 percent of the annual safe harvest level.) This year’s sport fishing cap is 300,000 pounds of walleye. Starting with the May 11 fishing opener, Mille Lacs anglers will have a limit of four walleyes and may harvest only those fish between 14 and 16 inches, with one over 28 inches. Fish under 14 inches, as well as all those between 16 and 28 inches, must be released. The harvest slot might widen by an inch, to 17 inches, on June 10 when the spring night ban comes off - if it appears anglers are apace towards staying under their quota.

Sternberg believes that within the parameters of treaty fisheries management DNR underestimates the Mille Lacs walleye population, sets unrealistically low quotas, and overly restricts the sport fishery. Negative effects include undue economic, political, and social harm. He offers comparisons with modern pre-treaty harvests and maintains that the lake has demonstrated it can safely produce more walleyes than today’s strict quotas and regulations allow.

Sternberg joins other critics, including some DNR personnel in their more candid moments, who observe that the system limits DNR management options and forces state biologists to pretend they can do what they can’t do (like producing reliable population estimates and realistic quotas), and to predict the impossible before a season even starts (like angler catch and the impacts of a regulation).

In his report, Dick Sternberg shows how an unprecedented pile-up of large fish has occurred at Mille Lacs after several years of harvest slots which perennially target medium- and smaller-sized walleyes, coupled with near complete protection of walleyes over 20 inches. That “big fish” trend may be deepening, with an overall imbalance between abundant predator fish (like walleyes, pike, and muskies) and preyfish (like perch, tullibees, and troutperch), which may be at historically low levels.

Sternberg steps beyond most critics by laying out “common sense” recommendations for change. He suggests that the Minnesota DNR ask the Court to allow more flexibility in DNR management of the sport fishery. That, among other things, would include a quota “range” rather than a precise quota based on imprecise population guesstimates. Sternberg says the DNR should be permitted to set management objectives and slot limits geared more to biological realities in the fish population. As the system works now, he emphasizes, size limits sidestep good biology and are aimed entirely at trimming pounds to satisfy a quota.

Other themes from Sternberg’s Mille Lacs report:

Impossible Population Estimates.
For decades, Mille Lacs Lake was managed much the same way as other large Minnesota lakes. The fish population was monitored by test-netting and other methods. An annual creel survey assessed angling pressure and fish harvests. These tools provided the information necessary to detect changes in fish populations and to make management decisions. With the advent of treaty management, a court-approved allocation system now requires DNR biologists to assess the walleye population with much more precision. Instead of tracking the “relative” abundance of walleyes through statistics such as number and weight of walleyes per gill net, and catch per angler-hour of fishing, they now must measure “absolute” abundance for the annual population estimates.

All concede these estimates are imprecise guesstimates.

Artificially Low Allowable Harvests.
Given angler harvest trends and fish population survey data over the years, it appears that Mille Lacs can safely sustain a higher walleye harvest than what treaty management allows. In the 1987-1996 pre-treaty decade, walleye angling harvests averaged 591,975 pounds (including hooking mortality). Since then, the combined tightly restricted sport harvests and band netting harvests under treaty management have averaged 391,055 pounds. This 34 percent cut in walleye harvest is unreasonable, given a relatively stable walleye population.

Low Population Estimates.
DNR’s annual fall gill net survey of the Mille Lacs fish population has been conducted mainly in shoreline areas, giving a biased view of the walleye population. Much of the lake, including the vast structureless “basin” areas, aren’t sampled at all. The recent addition of a few deep-water sets has shown that these new offshore sampling sites generally produce more and bigger fish. In 2001, the near shore nets had a somewhat lower-than-normal catch, while the offshore sets had the highest catch in history. What would appear to be a slight population decline in the nearshore nets might simply be a difference in seasonal walleye distribution/location patterns.

Predicting the Unpredictable.
Treaty fisheries management, with its annual safe harvest level, requires the DNR to propose and set regulations to keep anglers under their quota. To do that, biologists must pretend they can predict angler catch and harvest before a season begins - a near impossible task given the variables of weather, abundance of forage species which influence “the bite,” fishing pressure, and other factors contributing to higher or lower catches.

Too Much Hooking Mortality.
Not only does walleye hooking mortality count against the angler quota - 79,000 pounds in 2001! - it poses an ethical problem. Sternberg offers several suggestions aimed at reducing hooking loss, including avoidance of tight slot restrictions during warmwater periods. In 2001, adherence to treaty management’s strict quota triggered a narrowing of the harvest slot in early June, from 16-20 inches to 16-18 inches. “With 14 walleyes being released for every one kept, hooking loss skyrocketed and many of the fish that the tight slot was supposed to save were wasted,” Sternberg observed.

A “Big Fish” Problem?
Historically, in DNR gill net surveys, Mille Lacs has produced more walleyes over 20 inches than have Lake of the Woods, Leech, Rainy, Vermilion, and Winnibigoshish lakes. In the pre-treaty management era it was 17 percent. But during the five years of treaty management, with slot limits protecting large walleyes from harvest, the percentage of big walleyes has risen to about 30 percent. While this may thrill some anglers, it could be contributing to a predator-prey imbalance with worrisome implications for the fish population. Will Mille Lacs walleyes be experiencing lower growth rates, deteriorating condition, poor survival of young year-classes, and above-normal walleye cannibalism?

Declines of Forage Species.
Nobody knows exactly why, but indications are that Mille Lacs preyfish populations have dramatically declined. Adult tullibee (a prime forage for muskies, pike, and large walleyes) may be at an all-time low. DNR surveys indicate downward shifts in perch, troutperch, darters, young tullibee, young suckers, log perch, and minnows. Whatever the causes - including climatic and environmental factors, as well as angling regulations favoring larger predators - treaty management, with its sole emphasis on trimming pounds and meeting quotas, denies biologists the flexibility they need to set regulations that help keep the fish population in balance.

Dick Sternberg’s paper provides a lively analysis of DNR fish population and creel survey work at Mille Lacs. It includes text and graphics detailing trends in the walleye population; harvest data (catch rates; hooking loss, and fishing pressure trends); abundance of various forage or preyfish species; and various pre-treaty management and treaty management comparisons (exploitation rates, hooking mortality, etc.).

The Sternberg paper will stir interest and discussion in the fishing community, DNR management circles, and maybe - just maybe - among legislators and high state government officials. Sternberg urges more flexibility for fisheries managers, warning that the “tight constraints” of treaty management require them to ignore issues like population imbalance, “which poses a far more significant threat to the fishery than a quota infraction.”

His call for DNR to submit a new management plan to the Court flows from Sternberg’s belief that managers must be free to regulate with “biological sense” and more responsiveness to the lake’s fish population and the related economy. In his view, that includes a return to harvesting walleyes at historic levels. Barring a dramatic increase in fishing pressure or a deteriorating environment, he says, Mille Lacs should continue producing walleyes at pre-treaty management levels for years to come. Will DNR administrators, others in state government, and the Court agree with his arguments?