Status of the Fishery (as of 1/5/2016) Leech Lake is the third largest lake entirely within the boundaries of Minnesota and has approximately 112,000 surface acres. The lake is geographically located in three glacial zones and has an irregular shape with many large and small bays. The deepest area of the lake is located in Walker Bay where depths approach 160 feet deep. Approximately 80% of the lake is less than 35 feet deep. Similar to other large lakes in Minnesota, the fish community is dominated by species in the perch and pike families. Walleye, northern pike, and muskellunge are the primary predator species, while yellow perch and cisco serve as the principal forage. Leech Lake is well known among anglers as a tremendous multi-species fishery, including excellent fishing opportunities for walleye, yellow perch, northern pike, muskellunge, largemouth bass, sunfish, and black crappie. Leech Lake has been surveyed annually with standardized assessments since 1983. Establishment of long-term data sets on Leech Lake and Minnesota's other large walleye lakes allow biologists to compare current observations against historical averages. These long-term data sets can also provide insight into other lakes having similar physical and biological properties that are not sampled as frequently. Population metrics for a particular species, such as the highs and lows in gill net catch rates or the growth rates of fish, are constantly changing as they move from one extreme of their observed normal range to the other, much like a pendulum. While highs and lows are normal and rarely sustained beyond one year, consecutive observations at either extreme can be indicative of changes to an ecosystem. These may include invasive species introductions, shifts in habitat availability and/or quality, beneficial or adverse environmental conditions, and increased or decreased competition for resources between species or among different year classes of the same species. Regardless, it is important to remember that all populations of flora and fauna fluctuate dramatically and that this natural variability is strongly influenced by the changing environment in which they live as well as the other species of plants and animals they share it with. The MN DNR convened a citizen input committee (Leech Lake Fisheries Input Group; LLFIG) comprised of 16 stakeholders representing local and statewide interests in Leech Lake management. This group outlined sportfish population goals, objectives, and management actions. These recommendations were incorporated into DNR's 2016-2020 Fisheries Management Plan for Leech Lake. These management goals, where appropriate, are referenced in this report. Effective May 10, 2014 all walleye between 20.0-26.0 inches long must be immediately returned to the water, a possession limit of 4 walleye with one longer than 26.0" allowed in possession. This regulation is intended to provide additional harvest opportunity while still protecting most of the mature female walleye in the population, and received majority support from the public comment period held during fall 2013. All other species are currently managed under statewide fishing regulations. Aquatic invasive species currently found in Leech Lake include rusty crayfish, heterosporosis, curly-leaf pondweed, Eurasian watermilfoil, purple loosestrife, and banded mystery snail. Eurasian watermilfoil is beginning to establish in open-water areas of the lake. Other aquatic invasive species such as zebra mussels and spiny waterflea are increasing in prevalence throughout Minnesota and pose a likely risk. Anglers and boaters alike are encouraged to review and adhere to rules requiring proper bait disposal, draining all water from bait containers, livewells, bilge, and the watercraft, and properly inspecting and removing all plants and animals from the watercraft, anchor, and trailer when leaving a lake. Information on invasive species issues and prevention can be found at www.dnr.state.mn.us/invasives/index_aquatic/. Walleye: Since the Large Lake Program began in 1983, walleye gillnet catch rates have ranged from 4.6 fish/net (1993) to 13.4 fish/net (1988). The 2015 catch of walleye per gillnet set of 12.4 fish/net, the third highest catch rate in the time series, remained above the 1983-2015 average of 7.9 fish/net for the ninth consecutive year. Walleye sampled in gillnets ranged in length from 7 to 26 inches, and demonstrated a balanced size distribution. The average lengths of age-1 through age-4 walleye were 9.9, 12.2, 14.6, and 16.9 inches, respectively. Good 2011 through 2013 year-classes will provide harvest opportunities on the 2016 opener and continue to be available throughout the next several seasons. Additionally, 24% of walleye sampled in gillnets were 20-26" and will provide anglers the opportunity to catch a larger fish. The proportion of protected fish sampled in gillnets resembles the proportion of protected fish caught by anglers. Northern Pike: The 2015 gillnet catch rate of northern pike was 5.9 fish/net. Northern pike gillnet catch rates have remained relatively stable since 1983, ranging from 3.6 fish/net (1993) to 6.2 fish/net (1995) with an average of 4.8 fish/net. Northern pike captured in 2015 gillnet sets ranged in length from 12 to 34 inches. Muskellunge: Muskellunge from Miller Bay near Whipholt are currently collected and spawned for the statewide broodstock program every four years, with spawning operations most recently occurring in 2013. A total of 51 individual fish were captured in May of 2013, of which 23 were female and 28 were male. Females ranged in length from 39-53 inches, while males ranged from 31-46 inches. Females ranged in age from six through sixteen, while males ranged in age from five through fifteen. Yellow Perch: Gillnet catch rates of yellow perch have ranged from 12.1 fish/net (2013) to 37.7 fish/net (1995). The 2015 catch rate of 18.6 fish/net remains below the long term average (21.1 fish/net) but continues to increase incrementally from the record low observed in 2013 (12.1 fish/net). Yellow perch sampled in 2015 gillnet sets ranged in length from 3 to 12 inches. Of the total perch caught, 24% were 8 inches and longer and 6% were 10 inches and longer. Cisco: The 2015 catch rate of cisco per gillnet set was 5.5 fish/net and similar to the long-term average of 5.4 fish/net. Gillnet catch rates of cisco have varied considerably, ranging from 0.6 fish/net (2006) to 18.5 fish/net (1987). Warmer summers causing summer kills have likely been the source of cisco catch rates remaining relatively low since 1995. However, no summer kill events have been observed in the past three years. The 2012 and 2013 year classes were the most frequently sampled age classes in this survey. Lengths of cisco sampled ranged from 5 to 18 inches. Within the Leech Lake Indian Reservation the Whitefish limit is 25 and the Cisco (Tullibee) limit is 50, which is an exception to the statewide regulation. Daily and possession limits are the same. Largemouth Bass: A spring lakewide largemouth bass, bluegill, and black crappie electrofishing assessment occurred in springs 2012 and 2015. Catch rates for all largemouth bass were similar between 2015 (16 fish/hour) and 2012 (15 fish/hour). Catch rates for fish 15 inches were also similar between 2015 (6 fish/hour) and 2012 (5 fish/hour). Length and age frequency distributions of largemouth bass sampled in 2015 ranged from 4 to 18 inches and 1 to 15 years, respectively. Of all largemouth bass sampled in 2015, 35% were 15 inches or longer. Anglers can find quality bass fishing opportunities in the beds of mixed vegetation in most major bays. Bluegill: Catch rates for all bluegill were higher in 2015 (47 fish/hour) than in 2012 (31 fish/hour). Catch rates for fish 8 inches were lower in 2015 (3 fish/hour) than in 2012 (8 fish/hour). Length and age frequency distributions of bluegill sampled in 2015 ranged from 2 to 9 inches and 3 to 13 years, respectively. Of all bluegill sampled in 2015, 7% were 8 inches or longer. Anglers can find quality bluegill fishing opportunities in the beds of mixed vegetation in most major bays. Black Crappie: Catch rates for all black crappie were higher in 2015 (9 fish/hour) than in 2012 (5 fish/hour). Catch rates for fish 10 inches were similar between 2015(5 fish/hour) and 2012 (4 fish/hour). Length and age frequency distributions of black crappie sampled in 2015 ranged from 2 to 14 inches and 1 to 12 years, respectively. Of all black crappie sampled in 2015, 62% were 10 inches or longer. Anglers can find quality black crappie fishing opportunities in the beds of mixed vegetation in most major bays. Lake Whitefish and Cisco survey with Leech Lake Band of Ojibwe Division of Resource Management: In the fall of 2015 the DNR coordinated with the Leech Lake Band of Ojibwe, Division of Resource Management to collect additional data on cisco and lake whitefish harvested by Band members. Whitefish data were collected in October, while cisco data were collected in November. Harvested lake whitefish ranged in length from 18 to 27 inches and ages ranged from 7 to 30 years. Length and age frequency distributions of cisco harvested in 2015 ranged from 14 to 19 inches and 4 to 10 years, respectively.
- Zebra Mussel
- Eurasian Watermilfoil
Recreational activities such as recreational boating, angling, waterfowl hunting, and diving may spread aquatic invasive species. Some aquatic invasive species can attach to boats, while others can become tangled on propellers, anchor lines, or boat trailers. Many species can survive in bilge water, ballast tanks, and motors or may hide in dirt or sand that clings to nets, buckets, anchors, and waders. Fortunately, completing simple steps can prevent the transport of aquatic invasive species.