Topper

Topper Lake is a small, 47-acre lake with a maximum depth of 28.0 feet and is located completely within the Boundary Waters Canoe Area Wilderness (BWCAW). Access to the lake is considered moderate, with a relatively short 0.5-mile portage over a small hill from the Mayhew Lake Road spur trail. Water temperatures and dissolved oxygen concentrations in Topper Lake have supported conditions that are suitable for stocked trout during the summertime. Topper Lake has been managed for brook trout since 1971 and is currently stocked annually with 2,500 fingerlings during the fall. The long-range goal for brook trout is to maintain a minimum gillnet catch of 10.0 fish/net with two-year classes of fish greater than 10.0 inches present. In 2025, a standard survey was conducted on Topper Lake to monitor the brook trout population. The 2025 brook trout catch rate from gillnets was the lowest recorded at 2.5 fish/net and was well below the long-term median for the lake. Brook trout lengths ranged from 6.2 to 15.2 inches, with an average length of 10.2 inches. Less than half of the catch was greater than 10.0 inches, providing below average size structure compared to other area lakes. Aging results only found fish from the last three stocking events (2021, 2023, 2024). No brook trout were stocked in 2022 due to fish shortages and may have contributed to the low catch rate observed in 2025. It is unclear how significant the missed year class from 2022 influenced the catch rates during the 2025 survey or if the population has declined from the last survey. Brook trout growth in Topper Lake was fair, taking two years to reach 10.7 inches on average. Temperature and dissolved oxygen monitoring found suitable habitat for brook trout that does not appear to be limiting brook trout populations within the lake. Anglers looking to fish Topper Lake may find lower catches of brook trout that are smaller in size. Minnesota Lakes within Cook County continue to be susceptible to aquatic invasive species introductions. Invasive species have the potential to significantly alter fish communities and overall lake health. Anglers should clean watercraft and fishing gear, drain all water, and dispose of unused bait in the trash to prevent accidental introductions.

Brook Trout were abundant in Topper Lake in 2015, and their average size was within the normal range (0.40-1.17 lb/fish) for Brook Trout taken spring assessments in this area. The gill net catch of 16.00 Brook Trout/set exceeded the goal from the 2008 lake management plan (10.0 brook trout/set). All recent stockings were represented in the catch, and Brook Trout as old as four years were collected. Growth rates were below area averages for all ages sampled (1-4). Three-year-old fish reached a mean length of 10.6 inches by the end of their third year, compared to an area average of 12.7 inches. The presence of relatively high numbers of three- and four-year-old fish indicated harvest in this lake was probably not excessive. Results of this assessment seemed to indicate that survival of stocked fish was excellent. Good survival allowed the lake to provide relatively high quality fishing opportunities despite slower than average growth. No exotic or undesirable fish species were collected in 2015. As has been the case in past surveys high numbers of potential forage fish were collected in quarter-inch wire minnow traps. Fathead Minnows appeared very abundant, with lower numbers of Brook Stickleback also captured.

This was the second of three assessments scheduled in the 2008 lake management plan to determine whether survival and growth of stocked brook trout in this lake were adequate. Goals for brook trout in that plan were to maintain gill net catches of at least 10.0 fish/set, with two catchable-size (over 10 inch) year classes present. Brook trout were relatively abundant in Topper Lake in 2011, and their average size was within the normal range for brook trout taken spring assessments in this area. The gill net catch exceeded the long range goal from the 2008 lake management plan, and was above average compared to other spring assessments of stream trout lakes in the area. All recent stockings were represented in the catch, and brook trout up to five years of age were collected. Growth had been slower than average for this area; three-year-old fish reached an average length of 11.4 inches at the end of their third year, compared to an area average of 13.0 inches in similar lakes. The presence of relatively high numbers of three- and four-year-old fish indicated harvest in this lake was probably not excessive. Results of this assessment seemed to indicate that survival of stocked fish was excellent. Good long-term survival allowed the lake to provide relatively high quality fishing opportunities despite slower than average growth. No exotic or undesirable fish species were collected in 2011. Sampling with 0.25-in-mesh wire minnow traps confirmed the presence of several forage species, including Iowa darter, brook stickleback, fathead minnow, and northern redbelly dace.

Based on Minnesota DNR survey data, anglers target Brook Trout in Topper. See the full species list above for catch rates, size structure, and quality scores.

We don't have a confirmed public access point on record for Topper. Check the DNR LakeFinder page for current access details before you go.

Topper has a maximum depth of 28 feet, per Minnesota DNR data.

The most recent Minnesota DNR survey data for the main sport fish in Topper is from 2025.

No invasive species are on record for Topper in Minnesota DNR data. Always clean, drain, and dry your equipment to help keep it that way.