LAKE MANAGEMENT PLAN Region Area DOW Number County DOW Lake Name Acreage 2 Duluth F213 69-0041 St. Louis Bassett DOW: 436 Plan: 442 Long Range Goal: Manage for walleye with a gillnet catch rate greater than 7.0 per lift. Operational Plan: 1. Conduct a special assessment of spawning walleye in the spring of 2008 and 2009 using trapnets and/or night electrofishing 2. Conduct population assessments every 5 years beginning in 2011 with a full survey every third sampling (next survey in 2021). 3. Continue annual fall e~ectrofishin~ assessment for young-of-the-year and age-i walleye. 4. Stock Pike River strain walleye fingerlings in odd years at a rate of two pounds per littoral acre (392 pounds). 5. Conduct a largemouth bass spring night electrofishing assessment in 2011 and in conjunction with future surveys and assessments. Mid Range Objectives: Monitor the fish community. Evaluate biennial walleye stocking program after 201 1 assessment. Potential Plan: 1. Update information on use of Bassett Lake with an aerial recreational use survey in conjunction with other St. ~ouis and Lake County lakes. 2. Conduct a stratified random creel survey during the open water months on Bassett and in conjunction with Cadotte Lake. NARRATIVE: (Historical perspectives - various survevs; past manaqement; social considerations; present limiting factors; survey needs; land acquisition; habitat development and protection; commercial fishery; stockinq plans; other manaqement tools; and Check the appropriate boxes below: BWCAW [XI Superior National Forest Chippewa National Forest Leech Lake Indian Reservation [XI 1854 Ceded Territory. 1837 Ceded Territory Fond du Lac Indian Reservation Voyageurs National Park Primary Species Management: Walleye Area Supervisor Signature: Secondary Species Management: Bluegill, Black Crappie, Largemouth Bass Date: Regional Manager Signature: Date:
NARRATIVE: Bassett Lake is 442 acres, with 44% (196 acres) littoral area and a maximum depth of 21,feet. Bassett Lake is in lake class 5 and has an area priority rating of 9 on a scale of 1 to 14 (1 4 being the highest). VARIOUS SURVEYS: Full Surveys: 1951, 1960, 1993,2006 Population Assessments: 1973, 1983, 1988, 1996, 1999 Fall YOY Walleye Electrofishing Assessments: 1994-2000, 2002-2006 Recreational Use Survey: 1999-2000 A total of 17 fish species were collected in Bassett Lake using gillnets, trapnets, electrofishing, and seining between 1951 and 2006 (Table I). Fish species diversity increased steadily from 8 in 1951 to 15 in 2006. All interquartile range comparisons are for lake class 5. PAST MANAGEMENT: Stocking of walleye in Bassett Lake was primarily fry from 1946 through 1987 and fingerlings from 1990 through 1993 and 2001 through 2007 (Table 2). The three year-classes stocked from 2001 through 2005 were marked with a pectoral fin clip. Walleye gillnet catch-per-uniteffort (CPUE) ranged from 21.8 per lift in 1951 to 28.3 in 1960 (Figure 1 ). Catch rates from the most recent five investigations have been within the interquartile range (2.0-9.7). Proportional stock density (PSD) of walleye ranged from 23 in 1999 to 78 in 2006 and represented average size potential (Figure 2). Length at age 4 increased steadily from 13.1 inches in 1993 to 14.5 in 2006 (Table 3). This represented an increase in rate of growth from slow to typical compared to other Duluth Area lakes. Analysis of age distribution from investigations conducted since1 993 revealed strong 1988, 1994 and 1996 year-classes with relatively steady recruitment from 1985 through 2004 (Table 4). Correlation between yearclasses and years that walleye fingerlings were stocked was 44%, 12%, 0% and 59% in 1993, 1996, 1999 and 2006, respectively. However, analysis of data collected in 2006 for years that walleye fingerlings were clipped revealed 1 of 3 age 3, 1 of 16 age 4 and 1 of 14 age 5 walleye had a pectoral fin clip. Fall young-of-the-year (YOY) electrofishing was conducted on Bassett Lake from 1994 through 2006, except 2001. A downward trend in CPUE of both YOY and age I walleye was observed (Figure 3). The downward trend in YOY walleye CPUE was concurrent with an upward trend in bluegill trapnet CPUE (Figure 4). The trend in mean length of YOY walleye was flat (Figure 5). From a total of 28 yearling walleye collected one year after stocking only 3 (14%) were identified as having a pectoral fin clip. This indicates that the contribution of stocked fingerlings was minimal to these year classes. Bluegill fingerlings were stocked in Bassett Lake between 1921 and 1945 (Table 2). Bluegill trapnet CPUE has ranged from 0.0 per lift in 1960 to 44.7 in 2006 (Figure 6). The 2006 catch rate was more than two times greater than the upper end of the interquartile range (3.2-21.2). Bluegill PSD, which was above 60 from four samples collected between 1988 and 1999,
declined to 21 in 2006 (Figure 7). Length at age four declined steadily from 1993 to 2006 (Table 3, Figure 8). This represented a shift in rate of growth from fast to slow compared to other Duluth Area lakes. Analysis of age distribution from samples collected since 1993 revealed strong 1988, 1989, 1990 and 2002 year-classes and fairly consistent recruitment from 1 985 through 2002 (Table 4). Black crappie fingerlings were stocked in Bassett Lake between 1921 and 1945 (Table 2). Black crappie, which were first documented in assessment gear in 1999, increased to within the interquartile range (0.8-4.5) by 2006 (Figure 6). Black crappie PSD was 79 in 2006 and represents good length potential (Figure 7). Length at age 4 of 9.4 inches represented fast growth compared to other Duluth Area lakes. Analysis of age distribution from the sample collected in 2006 revealed a strong 2003 year-class. Largemouth bass fingerlings were stocked into Bassett Lake between 1921 and 1945 and from 1953 through 1965 (Table 2). Largemouth bass were sampled by assessment gear for the first time during the 2006 investigation at a rate of 0.3 per gillnet lift. Largemouth bass were also sampled by trapnet, shoreline seining and fall electrofishing. A total of 30 bass were collected during fall electrofishing. Mean length of bass sampled by electrofishing was 7.8 inches and all bass were age 1. Length at age 1 of 3.5 inches represents fast growth compared to other Duluth Area populations. Yellow perch gillnet CPUE ranged from 12.0 per lift in 1999 to 120.2 in 2006 (Figure I). All documented catch rates were above the interquartile range except for 1999 and the 2006 catch rate was 8 times greater than the upper end of the range (1.7-14.1). Yellow perch PSD, which ranged from 23 to 75 between 1960 and 1999, declined to 2 in 2006 (Figure 2). Length at age 4 remained steady between 6.2 and 6.6 inches from 1993 to 2006 (Table 3). Analysis of age distribution revealed steady recruitment from 1985 through 2004 (Table 4). Recruitment from 1995 through 1999 was not indexed. The Minnesota Department of Natural Resources (MDNR) has not stocked northern pike into Bassett Lake. Northern pike gillnet CPUE ranged from 0.5 per lift in 1951 to 7.1 in 1996 (Figure 1). Only three of seven catch rates were within the interquartile range (1.8-5.5). Northern pike PSD ranged from 0 in 1999 to 54 in 2006 and represented poor size potential (Figure 2). Although length at age 4 has been variable in recent assessments, it increased to 21.6 in 2006 (Table 3, Figure 9). This represented an increase from the slow to typical growth compared to other Duluth Area lakes. Analysis of age distribution from samples collected in 1993, 1996, 1999 and 2006 revealed consistent recruitment from 1989 through 2003 (Table 4)- White sucker gillnet CPUE, which had steadily increased from 4.1 per lift in 1951 to 16.7 in 1996, declined to 9.6 and 8.4 per lift in 1999 and 2006 respectively. The 2006 catch rate was
within the interquartile range (2.3-8.7). Other fish species sampled from Bassett lake during the 2006 survey include black bullhead, common shiner, golden shiner, Iowa darter, Johnny darter, central mudminnow, emerald shiner and pumpkinseed sunfish. Information was collected on aquatic vegetation, substrate type and water quality during lake surveys conducted in 1993 and 2006. Total species or species groups sampled along 20 transects increased from 23 in 1993 to 33 in 2006. The percentage of total species or species groups with frequency of occurrence ratings greater than or equal to 75% increased from 6% in 1993 to 21 % in 2003. Similarly, percentage of common abundance ratings increased from 13% in 1993 to 24% in 2006. Species rated as common in 1993 included claspingleaf pondweed, flatstem pondweed and hardstem bulrush. Species rated as common in 2006 included bushy pondweed, claspingleaf pondweed, flatstem pondweed, largeleaf pondweed, hardstem bulrush, sweetgale, variableleaf pondweed and whitestem pondweed. The most common substrate types identified during the 2006 survey were sand and rubble, which were identified along 95% and 75% of the transects, respectively. Results of laboratory water analysis revealed that total phosphorus levels in Bassett Lake had increased from 0.020 ppm in 1993 to 0.036 in 2006, representing a shift from low to moderate fertility. Moderate fertility lakes in Minnesota support good growth of aquatic macrophytes. Chlorophyll-a levels decreased from 12.2 ppb in 1993 to 11.6 in 2006. This may also reflect the shift toward higher diversity and abundance of aquatic macrophytes in Bassett Lake between 1993 and 2006. Other water quality parameters collected in 2006 indicate that Bassett is slightly alkaline with moderately soft water. There has been a shift from a simple fish community dominated by percids (walleye and yellow perch) to one that is more diverse and dominated by centrarchids (bluegill, black crappie, pumpkinseed sunfish and largemouth bass). There has been a concurrent increase in species composition and density of aquatic macrophytes. SOCIAL CONSIDERATIONS: A DNR administered concrete back-in access on Township land is located on the northwest side of the lake off County Highway #16. An aerial recreational use survey of 67 Duluth Area lakes was conducted between 1999 and 2000 and estimated approximately 9,110 total angling hours on Bassett Lake, of which 90% (8,224 h) was open water angling. This resulted in a fishing pressure of 20.9 hourslacre, which is categorized as heavy. The BassettICadotte Lakes Association has been actively engaged with the DNR concerning fisheries management planning on Bassett Lake. Members of the lake association assisted
DNR crews during the clipping of pectoral fins of fingerlings stocked in 2001, 2003 and 2005. Members of the association also collected information on utilization of Apple Creek by spawning walleye from approximately 1996 through 2005. Development on Bassett Lake has increased from 20 cabins in 1951 to 54 in 1960 and 75 in 2006. Of the 75 homes identified during the 2006 survey, 47 (63%) had open lots that extended to the shoreline. Conversion of undisturbed shoreline to turf-grass reduces infiltration (soaking in) rates of precipitation and increases the amount of nutrients and pollutants washed into the lake basin. Riparian landowners should attempt to reduce the negative impacts of run-off by restoring native buffers along the shoreline and reducing turfgrass. Water level on Bassett Lake is affected by beaver activity on the West Branch of the Whiteface River at the outlet of the lake. Lakeshore property owners have expressed concern about the water level being lowered by dam removal and how that may affect the distribution and density of submerged aquatic vegetation in the south end of the lake. A mechanical weed harvester has been in operation on Bassett Lake. There is no permit on file for the mechanical removal of submerged aquatic plants on Bassett Lake. LIMITING FACTORS: The high density of small bluegill may be limiting the recruitment of walleye in Bassett Lake (Figure 4). Although the electrofishing CPUE of YOY walleye has declined in recent years, the gillnetting CPUE of adult walleye has remained relatively steady. However, the size of walleye sampled by gillnet in 2006 was large. LAND ACQUISITION: None HABITAT DEVELOPMENT AND PROTECTION: Minimize impacts to aquatic resources by providing recommendations during permit review. Walleye spawning activity on Apple Creek was observed by a group of lake association members,from approximately 1996 through 2005. Observations on the creek, which were made during the night, were conducted between the lake and Highway #16. Although spawning activity varied from year to year, the lower portion of Apple Creek appeared to be important spawning habitat for walleye in Bassett Lake. Any future impacts to walleye spawning habitat in Apple Creek should be minimized. COMMERCIAL FISHERY: None.
STOCKING PLANS: Stock Pike River strain walleye fingerlings in odd years at a rate of two pounds per littoral acre (392 pounds). SURVEY AND EVALUATION PLANS: Assess recruitment of clipped walleye fingerlings to the spawning run electrofishing and/or trapnetting conducted in 2008 and 2009. Also collect information on largemouth bass. Conduct population assessments every 5 years beginning in 201 1 with a full survey every third sampling (next survey in 2021). Continue annual fall electrofishing assessment for young-of-the-year and age-i walleye Conduct a largemouth bass spring night electrofishing assessment in 201 1 and in conjunction with future surveys and assessments. OTHER MANAGEMENT TOOLS: Update information on angler use of Bassett Lake with an aerial recreational use survey in conjunction with other St. Louis and Lake County lakes. A stratified random creel survey would provide needed information on fish harvest and catch rates. Improve shoreline management at the DNR administered public access.
Number per set
Figure 2. Historical PSD* for fish sampled by gillnets from Bassett Lake, 1951-2006. (-) indicates that PSD was not calculated due to sample size less than 10. * Proportional Stock Density (PSD) is defuled as the number of fish longer than a designated quality length divided by the number of fish longer than a designated stock length divided by 100. Number in parentheses in data table is quality and stock length for that spccies (qualitylstock).
Number per hour on-time
Number per hour on-time
Figure 5. Fall young-of-the-year (YOY) walleye mean total lengths from Bassett Lake, 1995-2006. (-) represents assessment not completed. NIS represents no YOY walleye sampled. 10 h. c CI w 8 5 OD 6 5.I cr:.l 0 Y I 4 2 0 YOY 1994 5.6 1995 6.5 1996 5.8 1997 5.6 1998 6.1 1999 5.8 2000 NIS 2001-2002 6.3 2003 NIS 2004 4.9 2005 6.5 2006 NIS
Figure 6. Historical trapnet catch rates from Bassett Lake, 1951-2006.
Figure 7. Historical PSD* for fish sampled by trapnets from Bassett Lake, 1 951-2006. (-) indicates that PSD was not calculated due to sample size less than 10. rnn * Proportional Stock Density (PSD) is defmed as the number of fish longer than a designated quality length divided by the number of fish longer than a designated stock le~igth divided by 100. Number in parentheses In data table is quality and stock length for that species (quality/stock).
Figure 8. Mean length at age for bluegill sampled from Bassett Lake in 1993, 1996, 1999 and 2006. r - 8 'a -3 d 9 4 GI 8 10 6 4 2 0 Age-I Age9 Age3 Age-4 Aged Age-6 Age-7 Age-8 +I993 -t 1996 + 1999 + 2006 1.5 1.3 2.4 1.3 2.7 2.2 3.5 2.2 4.1 3.4 4.8 3.1 5.5 4.6 5.7 4.1 6.7 5.6 6.4 5.4 8.2 6.5 7 7.4 7.2 7.6 8 8.1
Figure 9. Mean length at age for northern pike sampled from Bassett Lake in 1993, 1996, 1999 and 2006. '
Table 1. Species sampled in Bassett Lake, 1951-2006. Yellow Perch Total Fish Sampled in FS X 8 X 9: X X X X X X X X 15 11 Survey Type: FS=Full Survey; PA=Population Assessment
Table 2. Stocking History for Bassett Lake, 1921-2007.
Table 3. Length at age for bluegill, northern pike, walleye and yellow perch sampled during investigations conducted from 1993 through 2006. Blueaill 1993 1996 1999 2006 age-1 8.4 6.7 7.4 6.3 age-2 14.7 12.4 13.0 13.4 age-3 19.1 16.5 16.2 18.4 northern pike age-4 23.1 22.0 18;O 21.6 age-5 27.7 24.3 22.3 ages 30.7 25.4 age-7 35.1 26.8 age-8' vellow ~erch
Table 4. Age distribution for fish species sampled from Bassett Lake in 1993, 1996, 1999 and 2006. <== Years Stocked * N represents the number of unclipped fish in the aged sample. C represents the number of clipped fish in the aged sample.