Knife Lake

How big is Knife Lake?

How deep is Knife Lake?

What kind of fish can you catch in Knife Lake?

Are there topographical lake maps available Knife Lake?

We have an topograpical map for online viewing near the top of this page. Lake-Link Pro users can download an print a topograpical map of Knife Lake (.pdf format) along with 2,700 more lake maps. For more information on all the benefits of Lake-Link Pro click here.

Knife Lake (Central)

Knife Lake (East

Knife Lake (East Central)

Knife Lake (North Central)

Knife Lake (West)

Knife Lake (West Central)

Are there places to eat and drink near Knife Lake?

Knife Lake is in Ecological Lake Class 2, which consists of 15 lakes in northeast Minnesota that are very large and deep with very irregular shoreline shapes, have little biologically productive shallow area, and have very clear and soft (unmineralized) water. Knife Lake is smaller and has clearer water than most of the lakes in this lake class. Knife Lake is on the Canadian border and 18 percent of the lake is in Ontario.

Knife Lake was thermally stratified on 07/10/2006 with surface temperatures of 72 F and bottom temperatures of 43-44 F. Good oxygen for trout (more than 5 ppm) was retained to the bottom in the north and central portion of the lake, and to within 10 feet of the bottom in the South Arm. Knife Lake is very rocky along the shoreline. The major inlets are from Little Knife Lake and from Eddy Lake. An old logging dam at the outlet of Knife Lake went out about 1980, lowering the level of the lake several feet.

Fish populations in the 2006 assessment were sampled with 10 shallow gillnets (set in or above the thermocline, at depths of 8-30 feet), and 16 deep gillnets (set below the thermocline, in depths of 40-83 feet). The shallow gillnets caught mostly warm and cool water fish species, while the deep gillnets caught mostly coldwater fish species. Three previous fisheries investigations on Knife Lake, dating back to 1980, used 15-26 deep gillnets to sample coldwater fish populations. Two of these previous investigations also used 10 shallow gillnets to sample fish populations. An earlier fisheries investigation on Knife Lake, in 1976, used 18 mixed-depth gillnets set from shallow water, through the thermocline, into deep water. The depths of the nets in 1976 were not accurately recorded, and the catch-per-gillnet data cannot be compared to recent investigations on this lake.

Shallow Water Fish Populations
Shallow water fish populations in 2006, as in previous investigations on this lake, were dominated by walleye, northern pike, smallmouth bass, and white sucker. These fish populations have been very stable over time, with the exception of walleye, whose numbers appear to have increased.

Walleye numbers in 2006 (8.6/shallow gillnet) were higher than in 1993 (7.1/shallow gillnet) or in 1983 (3.1/shallow gillnet). Walleye sizes in 2006 averaged 15.1 inches (1.3 lb), which was similar to previous investigations on this lake. The largest walleye in 2006 was 28.5 inches. Walleye growth was somewhat faster than normal (generally in the third quartile) by area standards. Most walleye stomachs were not checked for stomach contents, but walleye in shallow gillnet 19, in the east end of the South Arm, had many young-of-year perch in their stomachs. This suggests that perch in some areas of the lake are more abundant than indicated by the low overall numbers of perch caught (0.6/shallow gillnet).

Northern pike numbers in 2006 (2.6/shallow gillnet) were similar to previous catches in 1993 (1.0/shallow gillnet) and 1983 (3.0/shallow gillnet). Pike sizes in 2006 averaged 24.1 inches (3.4 lb), which was smaller than the average pike size of 27.7 inches for previous investigations on this lake. The largest pike in 2006 was 36.0 inches. Pike growth was faster than normal (in the third or fourth quartile, depending on the age) by area standards.

Smallmouth numbers in 2006 (0.9/shallow gillnet) were similar to previous catches in 1993 (0.5/shallow gillnet) and 1983 (1.2/shallow gillnet). Smallmouth bass are probably more abundant in Knife Lake than the gillnet catches indicate, as bass are "net shy" and tend to avoid capture in standard sampling nets. Smallmouth sizes in 2006 averaged 13.3 inches (1.3 lb), which was similar to previous investigations on this lake. The largest smallmouth in 2006 (caught in a deep water gillnet) was 18.0 inches. Smallmouth growth was faster than normal (in the third or fourth quartile) by area standards.

Rusty crayfish (Orconectes rusticus) were captured for the first time in the 1993 investigation, when two were caught in shallow gillnet 16, near the west end of the South Arm of Knife Lake. In 2006, 20 rusty crayfish and 6 northern clearwater crayfish (Orconectes propinquus) were captured in shallow gillnet 16. Northern clearwater crayfish were also caught nearby, in shallow gillnet 23 (12 crayfish), and in shallow gillnet 25 (15 crayfish). No native crayfish were caught during the 2006 investigation.

Rusty crayfish and northern clearwater crayfish are natives of the east-central United States and were probably brought to this area by anglers using them for bait. They are very aggressive and can become quite abundant, often resulting in the extirpation of native crayfish (usually Orconectes virilis). They can also destroy rooted aquatic vegetation and consume fish eggs and small fish.

A few of the northern pike and walleye examined in 2006 were infected with neascus (black spot). Most of the smallmouth bass had bass tapeworm larvae in their viscera. Neascus and bass tapeworm are common parasites that are native to the area. They cannot infect humans, are often removed by filleting fish, and are killed at temperatures used to cook fish.

Deep Water Fish Populations
Deep water fish populations in 2006, as in previous investigations on this lake, consisted of lake trout, burbot, lake whitefish, and cisco. These populations have been quite stable over time.

Lake trout numbers in 2006 (1.8/deep gillnet) were similar to previous investigations on this lake (range: 0.7-1.7/deep gillnet). Lake trout sizes in 2006 averaged 22.6 inches (4.1 lb), which was similar to previous investigations on this lake. The largest lake trout in 2006 was 30.0 inches. Lake trout growth, as determined by otolith ageing and compared to other area trout lakes, was average for young trout through age 8 and slower than average for older trout. Nine lake trout stomachs were examined in 2006. Three were empty and six contained ciscos.

Burbot numbers in 2006 (0.9/deep gillnet) were similar to previous investigations on this lake (range: 0.7-1.6/deep gillnet). Burbot sizes in 2006 averaged 15.2 inches (0.8 lb), which was similar to previous investigations on this lake. The largest burbot in 2006 was 20.4 inches.

Whitefish numbers in 2006 (6.0/deep gillnet) were similar to previous investigations on this lake (range: 5.8-7.9/deep gillnet). Whitefish sizes in 2006 averaged 14.2 inches (1.1 lb), which was similar to previous investigations on this lake. The largest whitefish in 2006 was 21.3 inches.

Cisco numbers in 2006 (5.9/deep gillnet) were similar to previous investigations on this lake (range: 2.6-11.2/deep gillnet). Cisco sizes in 2006 averaged 7.4 inches (0.1 lb), which was similar to previous investigations on this lake. The largest cisco in 2006 was 9.5 inches.

What is the average air temp for Knife Lake?