Frequently asked questions about Lake Superior Fisheries Management
Q. What is the goal of the Lake Superior Fisheries Management Plan? The long-term goal for fisheries management in the Minnesota waters of Lake Superior is:
A. "To protect the Lake Superior ecosystem, restore its watershed, and manage for a diverse, stable, self-sustaining fish community that allows for recreational, commercial and tribal fishing opportunities." In the goal statement a "diverse" fish community is one that includes different strains of native and introduced species that have established themselves through natural reproduction and are presently found in Minnesota waters. "Stable" means that although the abundance of various populations may fluctuate, they do so within a limited range. A "self-sustaining" community is one in which the fish species can sustain themselves largely through natural reproduction, but may at times require assistance through management actions, such as stocking.
Q. How many anglers fish Lake Superior?
A. Of the roughly 95,000 people who buy trout stamps annually, an estimated 20% fish Lake Superior for a total of 19,000 shore and boat anglers. To put this in perspective, the estimated number of individual anglers that fish Mille Lacs is much higher and ranges from 150,000-200,000 anglers.
Q. Do Lake Superior anglers get their money's worth?
A. Lake Superior fishery management is an expensive program when compared to other fisheries in the state, consuming approximately 4.5% of the total fisheries budget. Around 1.5 million resident and nonresident anglers fish in Minnesota. The percent of the total number of anglers estimated to fish in Minnesota's portion of Lake Superior is around 1%. Lake Superior anglers are getting a proportionately large share of the total fisheries budget. Although Lake Superior is a unique resource and offers diverse recreational opportunities, user groups must recognize that increased expenditures for Lake Superior fishery programs will be difficult to justify when viewed from a statewide perspective.
What is the MNDNR, Section of Fisheries doing to address the growing concern over increased development along the North Shore of Lake Superior?
A. Increased development can increase storm water runoff, pollution, nutrients and erosion. The Section of Fisheries will continue to evaluate and comment on permits issued by various agencies (MNDNR-Division of Waters (DOW), U.S. Army Corps, etc.) so that fishery habitat is not degraded, and is enhanced where possible by potential projects. We will continue to work with MNDNR-DOW, local units of government, the North Shore Management Board and other agencies to ensure criteria that protect fishery habitat are included in policy guidelines for zoning and development within the Lake Superior watershed. We will also work with forest managers to ensure that best management practices are implemented, and advocate for additional protection of the riparian areas near streams and wetlands.
Q. How might increased logging, new road and driveway construction, and increased ATV traffic in the forest impact water quality?
A. Many areas that were once remote are being impacted by these activities, which can increase nonpoint-source pollution to streams and degrade water quality. Increased development and activities in these areas increase runoff, erosion, nutrients and sedimentation. Many minor disturbances to the landscape can lead to a large cumulative impact and degradation in the water quality of a watershed.
Q. What can be done to reduce contaminants in Lake Superior fish?
A. Fortunately many contaminant levels have decreased over the last 30 years. The contaminants found in the flesh of lake trout and other fish are the result of industrial pollution. We must continue to lower discharges of toxic substances. The Lake Superior Binational Program seeks to establish zero discharge into Lake Superior. Unfortunately, some of the pollutants are produced in other areas and are deposited in Lake Superior through atmospheric deposition. It will take a national effort to eliminate or further reduce contamination. Pollution is regulated at the Federal and state levels. The MNDNR will maintain partnerships and keep up monitoring efforts. In the meantime, it is recommended that people trim fatty tissue from fillets and cook the fish so that fats and oils can drain away. This can reduce the concentration of some contaminants by as much as 50%.
Q. Why doesn't Lake Superior produce a fishery like Lake Michigan?
A. Lake Michigan is a much warmer and more productive system, which is better suited to salmon and rainbow trout that are adapted to warmer temperatures. Lake Superior is much colder and is better able to support native lake trout and lake herring as the primary predator and prey species. Lake trout and lake herring evolved in Lake Superior and are better adapted to its cold temperatures and available prey. Pacific salmon can survive in Lake Superior and have become naturalized. However, compared to Lake Michigan, their growth is slow and survival is poor. The physical environment of Lake Michigan is much more productive than Lake Superior. Lake Michigan has more in-lake shallow water habitat. Average surface temperature can be 10-15 degrees F warmer, and the optimal growing season can be 1-3 months longer, in Lake Michigan. The biological productivity of Lake Michigan is about 3 times that of Lake Superior, creating an environment better suited for growth and survival of Pacific salmon.
Q. How has the Lake Superior fish community changed since 1970?
A. Wild lake trout abundance has increased and may be approaching fully rehabilitated levels. Lake herring stocks have also rebounded in much of the lake, but continue to exhibit sporadic recruitment. The deep-water fish community composed mainly of siscowet lake trout, burbot, deep-water chubs and sculpin remains relatively undisturbed. Pacific salmon have become naturalized and are largely supported by self-reproducing populations, which makes continued stocking ineffective in most areas of the lake. Prey biomass has largely shifted from non-native rainbow smelt to native species, and high predation rates may limit any future recovery of rainbow smelt to historical levels. Managers have little influence on prey abundance as predatory impact is the driving force, and control of predator abundance is limited because most species are now self-sustaining. A potential threat to the recovering fish community remains the adverse affects of unwanted introductions and new introductions of exotic species.
Q. What can be done to bring back rainbow smelt?
A. The decline in abundance of rainbow smelt is one indication that the Lake Superior fish community is reaching a more stable predator-prey balance compared to the period before lake trout restoration. Smelt abundance is unlikely to increase significantly because there are now many more predators, lake trout and other naturalized salmonids, in the lake compared to the 1960s and 70s. Predation pressure, primarily from lake trout, is the overwhelming factor controlling the smelt population in Lake Superior. Reducing the very small recreational and commercial harvest that provides a valued food fish for human consumption would not significantly increase smelt abundance.
Q. Will the MNDNR expand the fishery for lake herring?
A. Perhaps, if there is a harvestable surplus available and harvest can occur without jeopardizing stocks, expansion may occur. If the harvestable surplus decreases or is not available, harvest will be decreased. We will use models and hydroacoustic techniques to estimate harvestable surplus. A harvest level will be set and be in place for 3 years and then be reevaluated. However, lake herring abundance has not yet recovered to historic levels and recruitment indices are sporadic. Although there are a couple of moderately strong year-classes, no extremely strong year-classes have recruited since the early 1990s.
Q. Is the MNDNR considering regulation changes for the recreational lake trout fishery?
A. The MNDNR is proposing a 1-over-25 inch regulation to preserve spawning-sized fish. Another proposal is to extend the lake trout season through the first weekend in October to afford additional angling opportunity. However, if model results indicate that mortality rates get too high, a bag limit reduction may possibly be considered. Also, regulations may vary among management zones to achieve objectives.
Q. Can the lake trout population sustain a commercial fishery in Minnesota?
A.The MNDNR recognizes the cultural heritage and the important role that commercial fishing has played along the North Shore. Commercial fishing provides fresh fish to local restaurants and stores that may be enjoyed by residents and tourists that do not have the opportunity to fish. An experimental assessment fishery that allows some harvest of lake trout is proposed provided that a harvestable surplus of lake trout is available and the fishery can be implemented in a sustainable manner. Implementation may vary by management zone and would not occur until 3 years after stocking has been discontinued in that zone. Although lake trout have made significant progress, restoration is not complete in Minnesota and it is best to proceed cautiously.
Q. What is a siscowet lake trout and what impact do they have on the fishery?
A. The siscowet lake trout is a deep-water form usually caught at depths greater than 300 feet. Siscowet are less desirable because of their high fat content and they are of limited food value due to high contaminant levels. Because siscowet were not as susceptible to lamprey, their numbers remained relatively high during the decline of lean lake trout. Siscowet are the most abundant predator in Lake Superior. There is evidence that siscowet rely on nearshore production for a significant portion of their lives and they therefore may compete with lean lake trout for resources.
Q. Why has the MNDNR proposed to discontinue stocking lake trout in Lake Superior along the central portion of the North Shore?
A. Survival of stocked lake trout has declined, while the abundance of wild lake trout has increased for all areas of the shore. The survival index of stocked lake trout and the abundance of wild lake trout have surpassed criteria established to discontinue stocking in the northern and central portions of Minnesota waters. The decrease in survival of stocked fish, along with the decrease in the smelt forage base that has occurred since the early 1990s, suggest that density-dependent factors govern growth and survival of lake trout and other predators and that their populations may be near carrying capacity. There is evidence that shows stocking fish where wild populations exist may displace the wild fish by competing for limited resources. Reduced lake trout stocking should give wild lake trout a better chance for success and may allow rehabilitation to proceed at a faster rate. Stocking still contributes to the fishery in the western end of the lake near Duluth, but wild fish continue to increase and results of stocking will be monitored.
Q. What changes are proposed for Chinook salmon management, and what might be the potential impact on the fishery?
A. We recommend that the Chinook salmon stocking program be discontinued. The program has proven ineffective at increasing the number of Chinook salmon that anglers catch. Criteria developed in 1998 with significant public input state that the Chinook salmon stocking program would be discontinued if fewer than 75 disease-free pair of Chinook salmon return to the French River for three consecutive years. Returns in 2003-2005 have been just 13, 20 and 9 pairs respectively. Discontinuing the stocking program will have little noticeable impact by anglers participating in the fisheries. Stocking contributes very little to the summer sportfish catch in Minnesota, less than 5 percent, with around 95% of the Chinook salmon catch resulting from natural reproduction. Continued stocking is unnecessary and does not make effective use of limited funds.
Q. Why doesn't the MNDNR stock coho salmon?
A. Coho salmon are now naturalized in Lake Superior, and provide a good fishery in Minnesota. It would not be effective for the MNDNR to invest in a costly hatchery program to produce what the lake already produces well. Past stocking of hatchery-reared coho salmon resulted in very disappointing return rates even when competition from other species was minimal. In the Lake Superior fish community with its present high predator abundance, survival of stocked coho salmon would be even less than in the pre-restoration period.
Q. What is happening with rainbow trout management? How will the LSMP differ from the 2003 Rainbow Trout Management Plan?
A. The new LSMP essentially incorporates the 2003 Rainbow Trout Management Plan (RTMP) as a chapter. There have been a few minor modifications to the RTMP, but for the most part the content of the RTMP is included verbatim in the Rainbow Trout Chapter of the LSMP. The minor modifications that have been made include the proposed changes in sanctuary dates on the Knife River system and criteria for reevaluating the steelhead fishery.
Q. What is the MNDNR doing to promote coaster brook trout rehabilitation?
A. The MNDNR has implemented very restrictive regulations to protect remnant stocks of coaster brook trout. Biological and habitat surveys indicate small populations with very limited habitat. It is important to preserve genetic variability of brook trout populations and a conservative approach that is the least risky to the genetic integrity of those populations is warranted. Allowing remnant stocks to rebuild while giving protection through restrictive regulations may be the best approach. The MNDNR continues to work with other management agencies on Lake Superior and is monitoring a number of projects that may prove useful for coaster brook trout rehabilitation in Minnesota.
Q. What is the status of lake sturgeon in Minnesota's waters of Lake Superior?
A. Rehabilitation of the lake sturgeon population in the St. Louis River estuary began with stocking of fingerlings in 1983 and continued through 2000. Survival of stocked fingerlings appears to be excellent. WIDNR has documented an increase in catch rates of larger lake sturgeon in assessments conducted along the Wisconsin shoreline of Lake Superior. Since about 1998, MNDNR began capturing an increasing number of lake sturgeon along the North Shore. Recently, anglers in the St. Louis River estuary have reported incidental catches of 40-50 inch sturgeon, suggesting the potential return of spawning adults. Large adults have also been observed below the Fond du Lac dam in the spring. Harvest of lake sturgeon in the Minnesota waters of Lake Superior and St. Louis River estuary is currently prohibited. The Pigeon River historically had a small lake sturgeon population that appears no longer present in any significant abundance. The Grand Portage Band of Chippewa is pursuing rehabilitating this population.
Q. How long will the LSMP be active and how will modifications to the plan be accommodated?
A. We anticipate that the LSMP will be active for 10 years. The plan is written to be flexible. There are many criteria in the plan that if reached will illicit a response. The LSMP may also need modification if there are major changes in the fish community, a shift in societal values placed on the Lake Superior fisheries resource, or a need to protect the resource from some unforeseen threat. Changes that may be necessary will occur with input from user groups and the public.