This was the second of three surveys included in the 2004 lake management plan. Initially, the surveys were to be used to determine whether walleye stocking was needed. That determination was made following the 2007 assessment, and walleye fingerling stocking began in 2008. Surveys will now be used to evaluate that stocking.
The long range goal for walleye in this lake is to achieve a minimum gill net catch of 4.0 fish/set, with at least 25% of that catch consisting of fish five or more years old. The catch goal was nearly met in 2011; the 2011 assessment yielded a gill net catch of 3.25 fish/set. The age goal for the catch was not met, since 80% of walleye taken in gill nets were three-year-old fish from the 2008 year class. Although the strength of that year class could well have been due to fingerling stocking done in that year, it should be noted that equally dominating year classes have been produced naturally in this lake in the past. No other strong year classes were evident in 2011. Growth of three-year-old walleye had been close to average; they reached an average length of 11.4 inches by the end of their third year. Those fish should have been showing up in angler's catches in 2011, and should drive some good fishing in 2012. Anglers should consider releasing some of those fish to extend the benefits of that strong year class, and help improve the quality of the fishery in this lake.
The long range goal for lake trout in this lake is to maintain a population yielding a minimum gill net catch of 1.0 fish/set. That goal was met by the catch in the 2011 assessment, as was the goal of providing some fish up to 25 inches in length. Several year classes, all naturally produced, contributed to the 2011 lake trout catch, although none stood out as having been exceptionally strong. Lake trout growth had been somewhat faster than average; seven-year-old fish reached an average length of 20.2 inches by the end of their seventh year, compared to an average of 18.1 inches for other lakes in this area. Lake trout as old as 18 years were collected, and many of the fish taken were over 10 years old.
Gunflint Lake serves as a control for the evaluation of a special regulation (a 30-in minimum size limit) on northern pike in Loon Lake. Both lakes support high-quality, and fairly low-density, northern pike populations. The northern pike gill net catch in Gunflint Lake in 2011 barely reached the normal range for a lake of this type, but was similar to catches seen in this lake since 1948. The mean weight for northern pike taken in gill nets (5.28 lb/fish) was at the upper end of the normal range, but was not unusually high for this lake. Northern pike recruitment was apparently low; although several year classes contributed to the catch, no fish younger than four years were taken. Northern pike growth had been somewhat slow; fish reached an average length of 20.7 inches by the end of their fourth year.
The smallmouth bass gill net catch and the mean weight for smallmouth bass collected in gill nets in 2011 were within normal ranges for a lake of this type, and were similar to catches and mean weights observed in this lake since 1976. Although several year classes, all naturally produced, contributed to the catch, it appeared that recent recruitment had been low. Most of the catch consisted of fish four years of age or older. Growth of older fish had perhaps been slightly faster than average; fish reached an average length of 11.3 inches by the end of their fifth year.
Forage for lake trout in this lake has been provided by cisco and rainbow smelt. The catch of cisco in gill nets in 2011, and their mean weight, were similar to those observed in this lake in the past. Rainbow smelt were still present, but no small-mesh gill nets were used in this assessment, so their abundance cannot be determined. The yellow perch gill net catch in 2011 was low for a lake of this class, but was not unusually low for this lake historically. Given the low yellow perch abundance typically seen in this lake, it is likely that walleye and northern pike depend mostly on cisco and smelt for forage.
No new undesirable, exotic, or invasive species were found in Gunflint Lake in 2011. The lake remains infested with spiny waterflea. Anglers leaving the lake should take extra care to drain all live wells, bait buckets, and bilges, and thoroughly dry their boat and all ropes, lines, and other equipment before using them in another lake.
- Spiny Waterflea
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.