Caribou Lake is located 6 miles south of Marcell, MN in the Big Fork River watershed. The lake has a surface area of 240 acres and a maximum depth of 152 feet. Caribou Lake is in ecological lake class #23. Other area lakes in this class include Bluewater and Larson Lakes. There is a US Forest Service public access on the southwest shore off State Hwy #38. Caribou Lake has historically been managed for lake trout. Since 1991, yearling lake trout have been stocked on an every other year basis. Because of the difficulty of ageing lake trout, all stocked yearlings since 1993 were given a specific fin clip to differentiate between stocked year classes and natural reproduction. Beginning in 2005, as part of a strain evaluation project, both Gillis Lake and Mountain Lake strain lake trout were stocked at a rate of 5 fish/acre. Each strain was given a fin clip to distinguish between the strains and assign ages to individual fish. The goal of the project was to evaluate survival and growth of the paired stockings at age-4 in waters across the state. In 2007, a total of 29 lake trout were caught in deep-water gill nets for a catch rate of 4.8/net. This is above the 2002 catch rate of 3.8/net and the management plan goal of 2.5/net. Sampled lake trout ranged from 8.7 to 30.8 inches, with an average length of 20.0 inches and an average weight of 4.2 pounds. Field inspections determined that ten of the captured lake trout had an identifying clip. Only one age-1 fish was captured, which was identified as a Gillis strain fish. Four of the clipped trout were identified as age-3; one of which was identified as Mountain Lake strain and the other three as Gillis strain. The other five clipped trout were identified as age-5 or older, and were not part of the strain evaluation. Interestingly, the remaining 19 trout (65.5%) were unclipped and assumed to be from natural reproduction. Unclipped trout ranged in length from 12.7 to 30.1 inches. Evaluating between the lake trout strains in Caribou Lake is difficult due to the limited number of samples obtained thus far. Other area lakes included in the strain evaluation project are Bluewater and Trout (31-410) Lakes. In 2007 assessments, only one age-3 fish was sampled in Bluewater Lake, and no age-3 fish were captured in Trout Lake. In addition, five clipped yearlings were captured in Bluewater Lake, and eleven marked yearlings were sampled in Trout Lake. Thus far, more Gillis strain lake trout have been sampled in Grand Rapids area lakes, but a longer evaluation period and more samples are needed to draw any meaningful conclusions. Catch rates for other species in deep-water gill nets are typically low and may not be good indicators of relative abundance. Other species sampled in gill nets included northern pike (0.3/net), smallmouth bass (0.8/net), rock bass (1.7/net), yellow perch (1.8/net) and bluegill (6.0/net). Northern pike have historically been sampled at very low levels, but have been of quality size. The two pike captured in 2007 were 24.4 and 31.8 inches in length. Warm water species sampled in trap nets (set near shore) included smallmouth bass (0.3/net), largemouth bass (0.6/net), rock bass (4.9/net) and bluegill (25.3/net). These results are similar to previous assessments.