Little Knife Lake

How big is Little Knife Lake?

How deep is Little Knife Lake?

What kind of fish can you catch in Little Knife Lake?

Are there places to eat and drink near Little Knife Lake?

Little Knife Lake is in Ecological Lake Class 1, which consists of 34 lakes in northeast Minnesota that are large, very deep, have little biologically productive shallow area along the shoreline, and have very clear and soft (unmineralized) water. Little Knife Lake is smaller than most of the lakes in this lake class.

The temperature/oxygen meter was not working during the 2006 investigation, but previous investigations showed that Little Knife Lake stratifies thermally in midsummer with surface temperatures of 70-75 F and bottom temperatures of about 40 F. Good oxygen for lake trout (more than 5 ppm) is retained to near the bottom. Little Knife Lake has a very rocky and steep shoreline, with very little aquatic vegetation. The inlet from Ottertrack Lake is a rocky drop that must be portaged. The outlet to Knife Lake is a navigable channel about 40 feet wide and several feet deep.

Little Knife Lake is on the Canadian Border, and about 35 percent of the lake is in Ontario. Three previous fisheries investigations (1980, 1983, and 1993) each used 8-12 deep gillnets, set below the thermocline at depths of 35-95 feet where the water temperature was 55 F or colder. Four of the 12 deep gillnets used in 1980 were set in Ontario waters, while all eight of the deep gillnets used in subsequent investigations were set in Minnesota waters.

Six shallow gillnets were used during the 1983, 1993, and 2006 investigations. Shallow gillnets in lake trout lakes are typically set above the thermocline, in water temperatures of 55 F or warmer. In Little Knife Lake, however, the very steep shoreline has led to the deeper ends of the shallow gillnets being set well into the thermocline, to depths of 30-35 feet where the temperatures were in the mid-40's F. As a consequence, more coldwater fish (primarily lake whitefish and cisco, but also burbot and lake trout) have been captured in the shallow gillnets in Little Knife Lake than in most lake trout lakes.

Shallow water fish populations in 2006 were dominated by walleye, white sucker, and smallmouth bass.

Walleye numbers in 2006 (5.5/shallow gillnet) were higher than previous investigations on this lake, which ranged from 3.7-4.2/shallow gillnet. Walleye sizes in 2006 averaged 16.3 inches (1.5 lb). The largest walleye was 23.0 inches. Walleye growth was normal (in the second or third quartiles, depending on the age) by area standards.

Smallmouth bass are likely more abundant in Little Knife Lake than indicated by the low numbers caught in the shallow gillnets in 2006 and previous investigations. Bass are "net shy" and tend to avoid capture in standard sampling nets. The largest smallmouth in 2006 (caught in the shallow end of a deep gillnet) was 19.0 inches.

Northern pike are not common in Little Knife Lake, which is not surprising given the very limited spawning habitat (shallow marshy areas) available in this lake. Pike sizes tend to be large in this lake due to the cisco and whitefish that are available as forage. The largest pike captured in 2006 was 39.8 inches.

Deepwater fish populations in 2006 consisted of lake trout, lake whitefish, cisco, and burbot.

Lake trout numbers in 2006 (1.8/deep gillnet) were higher than in previous investigations on this lake, which ranged from 0.3-1.3/deep gillnet. Only one small lake trout (8.9 inches) was captured in 2006; the rest ranged in size from 19-33 inches. Lake trout ageing in 2006 was done by grinding and burning otoliths, and was inconsistent in relating lengths with ages. Ages ranged from 3 to 26, and growth, based on one age 3 trout and four age 12 trout, appeared to be slower than average by area standards.

Whitefish numbers in 2006 (6.0/deep gillnet) were lower than in previous investigations on this lake, which ranged from 7.5-9.0/deep gillnet. Whitefish sizes in 2006 averaged 16.3 inches; the largest was 20.7 inches.

Cisco numbers in 2006 (4.1/deep gillnet) were lower than in previous investigations on this lake, which ranged from 4.9-13.1/deep gillnet. Cisco sizes in 2006 averaged 7.7 inches; the largest was 8.8 inches.

Burbot numbers in 2006 (1.4/deep gillnet) were lower than in previous investigations on this lake, which ranged from 1.5-4.0/deep gillnet. Burbot sizes in 2006 averaged 15.2 inches; the largest was 22.9 inches.

Some of the fish captured in 2006 were examined for diseases and parasites. All three of the smallmouth bass examined internally in 2006 had bass tapeworm larvae encysted in their viscera. One of the walleye had neascus (black spot). Some of the lake trout, whitefish, and cisco had roundworms in their air bladders. Some of the whitefish and cisco also had triaenophorus cysts in their muscle tissue. All of these parasites are native to the area and are common. They cannot infect humans, are often removed by filleting fish, and are killed at temperatures used to cook fish.

What is the average air temp for Little Knife Lake?