Fisheries
Blue Earth River Watershed
Fishing in Minnesota
Fishing is one of the most popular activities in Minnesota, and that level of interest requires tight regulations to ensure our lakes and rivers stay stocked with fish. Every time you go fishing in Minnesota, be sure to follow these fishing regulations laid out by the Minnesota Department of Natural Resources.
Learn more: MDNR Minnesota Department of Natural Resources Fishing Regulations
Fish Consumption
By following guidelines, you can lower your exposure to contaminants in fish, and still get the benefits of eating fish. First check the Statewide Safe-Eating Guidelines. Then check the waterbody specific safe-eating guidelines on lake finder to see if there are more restrictive guidelines for the fish species you catch.
Learn more about fish consumption at the Minnesota Department of Health website: Safe-Eating Guidelines
Fish in the Blue Earth River
There are many interesting fish species living in the Blue Earth River, tributaries, and lakes. You can learn more about fish in Blue Earth River lakes by visiting the Lakes Story Map. Learn more about fish in Minnesota by visiting the Minnesota Department of Natural Resources website: Fishing
Fish Barriers
In the Blue Earth River watershed, researchers found 22 barriers to fish migration by desktop reconnaissance and field observations. Rapidan Dam near Mankato is the most significant fish barrier in the Blue Earth River watershed. The Rapidan Dam was built over 100 years ago and it disconnected fish passage from the Minnesota River to the upper reaches of the Blue Earth River watershed. Additionally, perched culverts, waterfalls, and lake outlet structures are also fish barriers.
Fish Barriers, Blue Earth River
Of the 126 MPCA biological monitoring sites (map above), only four sites are downstream of Rapidan Dam and have full connectivity with the Minnesota River. Out of the remaining 122 sites, 110 are influenced only by Rapidan Dam, 11 have another barrier downstream of them, and one site has two extra barriers between the site and Rapidan Dam.
American Eel (Anguilla rostrate)
The American Eel has a long flexible and snake-like body and their preferred habitats are medium or large rivers having continuous flow and a mud or rock bottom that provides daytime cover such as boulders and log jams. They migrate from freshwater to saltwater to spawn. Females mature 10-20 years or older and average size is 91.4 cm (36 in.). In contrast, males mature sooner than females and the maximum size is 50.8 cm (20 in.).
Black Buffalo (Ictiobus niger)
The Black Buffalo has a rounded body that has the back, dark green or bronze on the sides, and dull yellow or off-white below. Also, they have a small ventral mouth and thick lips. Their preferred habitats are sloughs, impoundments, and both fast- and slow-flowing portions of rivers. Their diets are mollusks, insects, crayfish, duckweed, and algae. The Blas Buffalo spawns from April to mid-June. The average total length of the Black Buffalo is 50.3 cm (19.8 in.). The largest recorded in Minnesota was 86.9 cm (34.2 in.) in total length, 51 cm (20 in.) in girth, and weighed over 9 kg (20 lbs.).
Blue Sucker (Cycleptus elongatus)
The Blue Sucker has a small, slender head that tapers to a fleshy snout, and a thick lip that is directed downward. The body color is blue or bluish black. Their preferred habitats are deep, swift water in channels of large rivers with sand, gravel, or rubble bottoms. The Blue Sucker usually reach a length of more than 60 cm (23.6 in.). The Blue Sucker is a bottom feeder and their diets are aquatic insects, insect larvae, crustaceans, plant material, and algae. Moreover, the largest recorded in Minnesota was 77.2 cm (30.4 in.) long, 51.3 cm (20.2 in.) in girth, and weighed 6.4 kg (14 lbs. 2 oz.).
Lake Sturgeon (Acipenser fulvescens)
The Lake Sturgeon is a long-lived, slow-growing, late-maturing, and primitive fish that has a cartilaginous skeleton, bony plates, and the spiracle. The fish species have a flattened snout, with large, fleshy barbels, and a protractile mouth. Their preferred habitats are moderately clear, large rivers and lakes where have firm sand, gravel, or rubble bottoms. Their diets are insect larvae and other invertebrates, snails, leeches, small mussels, and small fish, and their barbels are used for searching preys. Their spawning season is between April and early June. The frequency of spawning is every 4-6 years for females and every 2-3 years for males. Also, the maturity is at 24-26 years old for females and at 8-17 years old for males. Moreover, the largest recorded in Minnesota was 2 m (6.6 ft.) in total length, and weigh over 45 kg (99 lbs.). Surprisingly, the maximum life span is 55 years for males and more than 150 years for females.
Ozark Minnow (Notropis nubilus)
The Ozark Minnow has a round body with silvery brownish-black above, silvery bronze below, a prominent black lateral stripe, and a silvery-white belly. The species is a medium-sized slender minnow and the average total length is 6.8-9.2 cm (2.7-3.6 in.). Their preferred habitats are clear small- to medium-sized streams of permanent flow where have slow current near gravel and pebble riffles. The spawning season in from May to August. Their diets are green algae, blue-green algae, diatoms, small insect larvae, and crustaceans. Both males and females mature at 2 years.
Paddlefish (Polyodon spathula)
The Paddlefish has a long, paddle-like snout, small eyes, and a shark-like tail. Moreover, it has blue-black or gray in color on the back and white below. Their preferred habitats are open waters of large rivers and river lakes. The Paddle fish feeds on zooplankton, and needs free-flowing rivers with gravel bars for spawning. Males mature at 7-9 years, and females mature at 9-12 years. The Paddlefish are long-lived species and survive for at least 20 years. Especially, females grow larger and live longer than males. The maximum size is 2.2 m (7.2 ft.) in total length and the weigh is over 23 kg (50 lbs.).
Redfin Shiner (Lythrurus umbratilis)
The Redfin Shiner has a terminal mouth, and a body laterally compressed. Breeding males have bluish black on the back and bluish silver on the sides. Also, fins are red to orange, and the membranes of the upper portion of the dorsal fin are black. The species is a medium-sized minnow and the total length is usually 3.5-6.5 cm (1.4-2.6 in.), with a maximum of 8.5 cm (3.3 in.). Their preferred habitats are low gradient turbid streams where have silt, gravel, or rubble. Their average life span is two years.
Suckermouth Minnow (Phenacobius mirabilis)
The Suckermouth Minnow has an inferior mouth and fleshy lips. Breeding makes have small tubercles and a bright iridescent blue and silver color on the body. The species is a medium-sized minnow and the total length is usually 6.5-10 cm (2.6-3.9 in.), with a maximum of 12.5 cm (4.9 in.). Their preferred habitats are riffles in low to moderate gradient warm water and highly turbid streams with gravel substrates. The spawning season in from May to August. The maximum life span is three years.
