St. Olaf

St Olaf Lake is a 91-acre lake located approximately 3.5 miles east of the town of New Richland in Waseca County. The county-owned public access is located on the north shore off County Highway 8. St Olaf Lake has a maximum depth of 33 feet, with approximately 55% of the lake less than 15 feet. St Olaf Lake is primarily managed for Bluegill, Largemouth Bass, and Northern Pike and secondarily for Black and White Crappie. The management plan calls for stocking 25,000 Northern Pike fry annually into the connected wetland near the public access. A special regulation protecting Northern Pike under 30 inches from harvest has been in place since 1998. St Olaf Lake is one of 23 lakes statewide included in the Sentinel Lakes program which aims to capture long term changes in biological, physical, and chemical characteristics. A standard survey was conducted the week of June 21, 2022, as part of a regular monitoring program conducted by the Minnesota DNR. A standard survey is used for sampling a wide range of fish species during the summer months using standard methods (i.e., standard time of year, set sampling stations, taking water clarity readings and oxygen/temperature profiles, etc.) and gears (i.e., lake survey gillnets, trap nets, and spring electrofishing for Largemouth Bass). This survey was intended to assess the fish community by deploying 3 gill nets and 8 trap nets, as well as recording water quality parameters. A total of 1,325 Bluegills were sampled with trap nets for a catch rate of 165.6/net. Catch rates since 1984 have varied from 33.3/net in 1996 to 213.3/net in 1998 with a mean of 101.9/net. Bluegill lengths ranged from 4.0 to 8.2 inches with an average of 6.3 inches. Fish from both gears ranged from age-3 to age-10 with 8 year-classes present. On average, fish did not exceed quality length (6.0 inches) until age-5, indicating slow growth relative to other area lakes. Bluegills continued to be an important part of the St Olaf fishery in 2022, with many quality-size fish available to anglers. A total of 145 Largemouth Bass were sampled with boat electrofishing for a catch rate of 153.4/hour. This represented the highest catch rate ever recorded with boat electrofishing on St Olaf Lake. Catch rates since 2000 have varied from 22.0/hour in 2000 to 153.4/hour in 2022 with a mean of 70.1/hour. Largemouth Bass lengths ranged from 3.9 to 20.2 inches with an average of 10.5 inches. Scales were collected to age Largemouth Bass. Largemouth Bass ranged from age-1 to age-13 with 11 age classes included. On average Largemouth Bass reached quality size (12.0 inches) in their fifth growing season indicating slow to moderate growth compared to other area lakes. Northern Pike were sampled at a rate of 5.7/net, which was just above the lake-class first quartile (4.8/net). Catch rates since 1984 have varied from 0.3/net in 1990 to 9.7/net in 2002 with an average of 4.0/net. Catch rates have averaged 6.1/net since the implementation of the 30-inch minimum length limit in 1998. Northern Pike lengths in 2022 ranged from 20.4 to 35.0 inches with an average of 25.5 inches. Northern Pike ranged from age-2 to age-8 with 6 year-classes present. On average, fish reached quality length (21.0 inches) by age-3, indicating fast growth relative to other area lakes. The favorable size structure and growth provide anglers a high-quality opportunity. Black Crappies were sampled with trap nets at a rate of 2.4/net, which was above the lake-class average (1.8/net). White Crappies were sampled with trap nets at a rate of 0.1/net. Both species have declined in recent surveys. Trap net catch rates for both species exceeded 16.0/net from 2002 to 2010. Since 2010, catch rates have fallen to an average of 5.1/net for Black Crappie and 0.7/net for White Crappie. Lengths ranged from 6.1 to 13.9 inches with an average of 10.5 inches for Black Crappies and from 7.3 to 12.8 inches with an average of 9.5 inches for White Crappies. Black Crappies from both gears ranged from age-3 to age-10 with 8 year-classes present. On average, Black Crappies reached quality length (8.0 inches) by age-3, indicating moderate growth rate relative to other area lakes. Three Yellow Perch were sampled with gill nets for a catch rate of 1.0/net, which was the third lowest on record. Catch rates since 1984 have been erratic varying from 0.0/net in 1996 to 33.3/net in 2014 with a mean of 7.3/net. The two highest catch rates in 1990 (13.5/net) and 2014 (33.3/net) coincided with the two lowest Northern Pike catch rates on record (0.3/net in 1990 and 1.3/net in 2014). This type of relationship suggests a strong predator-prey influence on both species. When Yellow Perch were abundant, an increase in Northern Pike numbers followed and drove Yellow Perch numbers down and so on. This may also explain the recruitment gaps seen in the Northern Pike population. At times in the past Yellow Perch have likely been a part of the angler's creel but their real value was providing prey for the fast-growing trophy Northern Pike population in St Olaf Lake. A total of 31 Yellow Bullheads were sampled with gill nets in 2022. This was by far the highest on record. Yellow Bullheads have been rare with gill net catch rates averaging 0.6/net. Other area lakes have also seen a spike in Yellow Bullheads. No Common Carp were sampled in 2022. In 2016 Two Common Carp were sampled with trap nets for a catch rate of 0.2/net. Catch rates since 1984 have averaged just 0.2/net and have never exceeded 1.0/net. The Common Carp population in St Olaf Lake has subsisted at an almost undetectable level and likely poses little threat to current fish management objectives. Other species sampled in 2022 include Pumpkinseed and hybrid sunfish. Water quality parameter measurements included secchi depth, water temperature, and dissolved oxygen readings. At the time of this survey, secchi depth was 6.0 feet, indicating moderate water clarity. Water temperatures and dissolved oxygen readings throughout the water column ranged from 79.0 degrees Fahrenheit and 7.7ppm at the surface to 49.3 degrees Fahrenheit and 0.0 ppm at 30 feet. The formation of a thermocline was detected at a depth of 13 feet. Anglers can play an important role in maintaining or improving a fish population by practicing selective harvest. Selective harvest allows for the harvest of smaller fish for consumption, while encouraging the release of medium to large fish that may contribute to natural reproduction. This practice helps maintain balance in the fish populations and provides anglers the opportunity to catch more and larger fish in the future. Additionally, smaller fish often taste better and have fewer contaminants than larger, older fish from the same water body. Shoreline property owners also play an important role in the overall health of an aquatic ecosystem, including the fish population. Natural shorelines, including vegetation, woody debris, and bottom substrates, provide valuable habitat for fish and wildlife, help maintain water quality, and reduce bank erosion. Cattails and bulrushes are particularly beneficial for fish spawning, rearing, and feeding. By leaving natural shorelines unaltered or restoring them to natural conditions, shoreline property owners are doing their part to maintain or improve a healthy ecosystem in the lake and protect the resource for future generations. -Tyler Fellows, fisheries specialist

Introduction St Olaf Lake is a small (91 acre) lake located approximately 3.5 miles east of the town of New Richland in Waseca County. The county owned public access is located on the north shore off of County Highway 8. It has a maximum depth of 33 feet, with approximately 55% of the lake classified as littoral area. St. Olaf Lake is primarily managed for Bluegill, Largemouth Bass, and Northern Pike and secondarily for Black and White Crappie. The management plan calls for stocking 25,000 Northern Pike fry annually into the connected wetland near the public access. A special regulation protecting Northern Pike under 30 inches from harvest has been in place since 1998. St Olaf Lake is one of 23 lakes statewide included in the Sentinel Lakes in a Changing Environment (SLICE) program which aims to capture long term changes in biological, physical, and chemical characteristics. It was surveyed the week of June 20, 2016 as part of a regular monitoring program conducted by the Minnesota DNR. This survey was intended to assess the fish community by deploying 3 gill nets and 9 trap nets, as well as recording water quality parameters. ? Bluegill A total of 516 Bluegills were sampled with trap nets for a catch rate of 57.3/net, which consistent with historical catch rates. Since 1984, catch rates have varied from 33.3/net in 1996 to 213.3/net in 1998 with an average of 95.5/net. Lengths ranged from 3.0 to 8.2 inches with an average of 6.6 inches. An additional 4 Bluegills ranging from 6.5 to 8.0 inches were sampled with gill nets. Fish from both gears ranged from 1 to 10 years old with 10 year-classes present. On average, fish did not exceed 6.0 inches until 4 years old, indicating moderate growth relative to other area lakes. Bluegills continued to be an important part of the St Olaf fishery in 2016, with many quality size fish available to anglers. Largemouth Bass A total of 99 Largemouth Bass were sampled with boat electrofishing for a catch rate of 106.4/hour. This represented the highest catch rate ever recorded with boat electrofishing on St Olaf Lake. Since 2000, catch rates have varied from 22.0/hour in 2000 to 106.4/hour in 2016 with an average of 58.2/hour. Lengths ranged from 3.2 to 20.0 inches with an average of 10.4 inches. To summarize, numbers and sizes were of high quality in 2016 and management goals were easily met. Northern Pike Northern Pike were the most commonly sampled species with gill nets with a total of 14 fish for a catch rate of 4.7/net. Since 1984, catch rates have varied from 0.3/net in 1990 to 9.7/net in 2002 with an average of 4.0/net. Since the implementation of the special regulation in 1998, catch rates have averaged 6.1/net, which meets our management goal of 6.0/net. Recent catch rates of 1.3/net in 2014 and 4.7/net in 2016 are concerning however and may indicate a problem with recruitment or noncompliance with the regulation. Lengths in 2016 ranged from 17.9 to 37.8 inches with an average of 26.5 inches. Six additional Northern Pike ranging from 16.7 to 20.9 inches were sampled with trap nets. Fish from both gears ranged from 1 to 10 years old with 5 year-classes present. The gaps in age groups points to a lack of recruitment during those years. On average, fish reached 21.0 inches by 2 years old, indicating fast growth relative to other area lakes. Overall, Northern Pike numbers have declined below the management goal but favorable lengths and growth provide anglers a high quality opportunity. Crappie Species Both Black and White Crappies inhabit St Olaf Lake. To tell them apart, you can look at the patterns on the sides of the fish as well as count the spines on the dorsal fin (top fin on the back). Black Crappies tend to be more mottled in appearance with black blotches and White Crappies tend to have mottling that forms vertical bars. When counting the hard spines on the dorsal fin, Black Crappies usually have 7-8 and White Crappies usually have just 5-6. Black Crappies were sampled with trap nets at a rate of 6.7/net. White crappies were sampled with trap nets at a rate of 1.0/net, which indicated moderate to high numbers were present relative to similar lakes. Both species have declined in recent surveys. From 2002 to 2010, trap net catch rates for both species exceeded 16/net. Since 2010, catch rates have fallen to an average of 6.5/net for Black Crappie and 1.0/net for White Crappie. Lengths ranged from 4.1 to 13.2 inches with an average of 7.1 inches for Black Crappies and from 3.9 to 12.1 inches with an average of 7.1 inches for White Crappies. Black Crappies from both gears ranged from 1 to 11 years old with 9 year-classes present. On average, Black Crappies reached 8.0 inches by 5 years old, indicating moderate growth relative to other area lakes. Despite the recent decline, the collective trap net catch rate of both species exceeds the management goal of 5.0/net and size structure was favorable to anglers. Yellow Perch A single 7.8 inch Yellow Perch was sampled with gill nets for a catch rate of 0.3/net, which was the second lowest on record. Since 1984, catch rates have been erratic varying from 0.0/net in 1996 to 33.3/net in 2014 with an average of 8.0/net. The two highest catch rates in 1990 (13.5/net) and 2014 (33.3/net) coincided with the two lowest Northern Pike catch rates on record (0.3/net and 1.3/net, respectively). This relationship suggests a strong predator-prey influence on both species. When Yellow Perch were abundant, an increase in Northern Pike numbers followed and drove Yellow Perch numbers down and so on. This may also explain the recruitment gaps seen in the Northern Pike population. At times in the past Yellow Perch have likely been a part of the angler's creel but their real value was providing forage for the fast growing trophy Northern Pike population in St Olaf Lake. Yellow Bullhead Just 4 Yellow Bullheads total were sampled with gill and trap nets in 2016. Since 1996, Yellow Bullheads have been rare with gill net catch rates averaging 0.6/net. They do not play a major role in the lake's fish community. Common Carp Two Common Carp were sampled with trap nets for a catch rate of 0.2/net. Since 1984, catch rates have averaged just 0.2/net and have never exceeded 1.0/net. Although nonnative, the Common Carp population in St Olaf Lake has subsisted at an almost undetectable level and likely poses little threat to current fish management objectives. Other Species Other Species sampled in 2016 include Golden Shiner, Pumpkinseed, and hybrid sunfish. Anglers can play an important role in maintaining or improving a fish population by practicing selective harvest. Selective harvest allows for the harvest of smaller fish for consumption, while encouraging the release of medium to large fish that may contribute to natural recruitment. This practice helps maintain balance in the fish community and provides anglers the opportunity to catch more and larger fish in the future. Additionally, smaller fish often taste better and have fewer contaminants than larger, older fish from the same water body. Shoreline property owners also play an important role in the overall health of an aquatic ecosystem, including the fish population. Natural shorelines, including vegetation, woody debris, and bottom substrates, provide valuable habitat for fish and wildlife, help maintain water quality, and reduce bank erosion. By leaving natural shorelines unaltered or restoring them to natural conditions, shoreline property owners are doing their part to maintain or improve a healthy ecosystem in the lake and protect the resource for future generations. -Sky Wigen, Fisheries Specialist

Saint Olaf Lake was surveyed the week of June 14th, 2010 as part of the first phase of SLICE (Sentinel Lakes in a Changing Environment) monitoring. Trap net returns were similar to 2009 results. Ice out northern pike trap netting and early season vegetation point sampling were also completed. Largemouth bass electrofishing was not completed because the boat was not operational until late summer. Black crappie averaged 25 fish per trap net lift. Bluegills averaged 119 fish per trap net lift. White Crappie averaged 37 fish per trap net lift. All bluegill and crappie catch per unit effort values exceeded the upper quartile for class 28 lakes. St. Olaf's centrarchid panfish community is largely made up of small and characteristically stunted fish. Other fish caught include common carp, golden shiner, hybrid sunfish, and pumpkinseed. Beach seines and backpack electrofishing as part of Index of Biotic Integrity sampling found species captured in trap nets, as well as spottail shiner, yellow perch, northern pike and johnny darter. Anglers can help maintain or improve the quality of fishing by practicing selective harvest. Selective harvest allows for the harvest of smaller fish for table fare, but encourages release of medium- to large-sized fish. Releasing these fish can help maintain balance in the fish community in St. Olaf Lake and provide anglers the opportunity to catch more and larger fish in the future. Shoreline areas on the land and into the shallow water provide essential habitat for fish and wildlife that live in or near Minnesota's lakes. Overdeveloped shorelines cannot support the fish, wildlife, and clean water that are associated with natural undeveloped lakes. Shoreline habitat consists of aquatic plants, woody plants, and natural lake bottom soils. Plants in the water and at the water's edge provide habitat, prevent erosion, and absorb excess nutrients. Shrubs, trees, and woody debris such as fallen trees or limbs provide good habitat both above and below the water and should be left in place. By leaving a buffer strip of natural vegetation along the shoreline, property owners can reduce erosion, help maintain water quality, and provide habitat and travel corridors for wildlife.

Based on Minnesota DNR survey data, anglers target Largemouth Bass, Black Crappie, Northern Pike, White Crappie, and Green Sunfish in St. Olaf. See the full species list above for catch rates, size structure, and quality scores.

Minnesota DNR records list public access for St. Olaf. Check the DNR LakeFinder page for the launch type and directions before you go.

St. Olaf has a maximum depth of 33 feet, per Minnesota DNR data.

The most recent Minnesota DNR survey data for the main sport fish in St. Olaf is from 2022.

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