Rock Lake

How big is Rock Lake?

How deep is Rock Lake?

What kind of fish can you catch in Rock Lake?

Are there boat launches on Rock Lake?

Are there places to eat and drink near Rock Lake?

What aquatic invasive species are found in Rock Lake?

Rock Lake is a 175-acre lake located four miles south of Maple Lake in central Wright County. It has a maximum depth of 37 feet and 57% of the lake's surface area is considered littoral (less the 15 feet). The watershed is small (1,124 acres) and primarily agricultural (cultivated crops and hay/pasture). As such the water clarity is generally poor with a 10 year average Secchi reading of 3.3 feet. There is a public access located on the east side of the lake with room for 7 or 8 vehicle/trailer combinations. A standard lake survey was conducted in 2016 to monitor changes in the fishery from the last survey completed in 2006. In addition to the standard lake survey, an Index of Biotic Integrity (IBI) survey was conducted in August and results from that survey will be summarized in another report.

Rock Lake has a history of Walleye fingerling stocking; however from 1997 to 2000 fry were stocked in an effort to produce stronger year classes. Unfortunately, fall electrofishing surveys showed little fry survival so Walleye management reverted back to stocking fingerlings every other year in 2001.

The 2016 Walleye catch was the highest on record and was near the upper end of what we would expect to see for the lake class. Walleye ranged in length from 10 to 22 inches with an average length of 19 inches. Six-year classes were sampled during the survey with the 2008 and 2014 year classes comprising 66% of the sample. Growth of Walleye was faster than the statewide average reaching 13 inches in 2 years and 19 inches by age 5.

The catch of Northern Pike was similar to 2006 and was in the lower range of expected values for similar lakes. Only thirteen pike were sampled during the survey and they ranged in length from 18 to 27 inches with an average length of 22 inches.

Anglers are encouraged to harvest smaller pike (under 22 inches) and release the larger ones to help achieve a more balanced fish community and promote good growth rates. Lower pike numbers may also increase the survival of stocked Walleye and allow Yellow Perch numbers to increase. Higher perch populations are desirable as they are an important prey species for both Walleye and Northern Pike.

The catch of Yellow Perch was higher than the 2006 survey and the same as the 1996 survey, but still on the low end of what would be expected for similar lakes. Perch ranged in length from 5 to 9 inches with an average length of 7 inches.

Anglers can expect to see quality Largemouth Bass fishing on Rock Lake. Largemouth Bass were sampled by day-time electrofishing on May 18, 2016. A total of 127 bass were sampled in 1.57 hours of sampling effort for a catch rate of 80.8 fish/hr. This is nearly two times higher than the average catch rate for Sauk Rapids Area lakes. Largemouth Bass ranged in length from 5 to 19 inches with an average length of 13 inches.

The Bluegill catch was similar to 2006. Bluegill ranged in length from 4 to 9 inches with an average length of 6 inches. This was within the normal range for similar lakes and anglers can expect to see fish over 9 inches.

Rock Lake offers a unique opportunity for anglers in the area as it has a good population of both Black and White Crappie. The trap net catch rate of Black Crappie was significantly higher than recent surveys, but was within the range of expected values for similar lakes. The gill net catch, however, was much higher and well above what would be expected. Black Crappie ranged in length from 5 to 13 inches with an average length of 7 inches. The gill net and trap net catch of White Crappies was both higher than 2006 and within the range of expected values for similar lakes. White Crappie ranged in length from 6 to 14 inches with an average of 8 inches.

Yellow Bullhead were also captured at a very high rate and anglers can expect some quality sized fish. Yellow Bullhead ranged in length from 8 to 14 inches with a mean length of 12 inches.

Other species sampled during the survey included: Black Bullhead, Bowfin, Brown Bullhead, Common Carp, Golden Shiner, Green Sunfish, Hybrid Sunfish, Pumpkinseed and White Sucker.

What is the average air temp for Rock Lake?