Official State of Iowa Website Here is how you know

Grass Carp

Grass Carp, photo courtesy of Noel M. Burkhead, copyright Noel M. Burkhead, USGS, Nonindigenous Aquatic Species,


Elongate, chubby body that is torpedo-shaped. The body is dark olive, shading to brownish-yellow on the sides with a white belly and large, slightly outlined scales. The terminal mouth is slightly oblique with non-fleshy, firm lips, and no barbels. The complete lateral line has 40 to 42 scales. The dorsal fin has 8 to 10 soft rays, and the anal fin is set closer to the tail than most cyprinids. Broad, ridged pharyngeal teeth are arranged in a 2, 4-4, 2 formula.


Grass Carp Distribution

Widely distributed throughout Iowa in ponds and man-made lakes, but it is not abundant in any location. Commercial fishermen report rare catches of Grass Carp from the Mississippi and Missouri Rivers. Primarily a big river fish, it has been found in the Mississippi and Missouri Rivers. It often escapes from ponds and impoundments where it is stocked and has also occasionally been found in Iowa’s interior rivers and streams, including streams in the Skunk, lower Iowa, Maquoketa and Winnebago River watersheds.


Aquatic macrophytes, and since they are voracious feeders, they are used to control aquatic invasive plants in small lakes and pond. They are not effective in controlling filamentous algae (moss) or duckweed problems in ponds.

State Record

85 lbs 8 oz, 48 in.- Greenfield Lake, Adair County, May 1, 2007 - Jesse Lane, Greenfield, IA

Expert Tip



Grass Carp is an exotic minnow that was imported into the United States from eastern Asia in 1963 to control aquatic invasive plants. They were first brought to Iowa in 1973 by the Iowa Conservation Commission. Research conducted in Iowa has shown that Grass Carp have harmful effects on water quality and fish habitat; the Iowa DNR no longer stocks Grass Carp in public water bodies.

The Grass Carp is most often found in large rivers, but is stocked in impoundments, ponds and lakes. It prefers swift, warm waters with slack current and aquatic plants. In its native habitat, Grass Carp prefer turbulent reaches of large rivers. Some investigators are concerned because the Grass Carp’s big appetite for aquatic plants may lead to the destruction of suitable habitat for many native fish and waterfowl. 

Grass Carp have specialized and restrictive river spawning needs, but young fish have been sampled in Iowa rivers. Natural spawning is impossible in standing water. Growth of Grass Carp is nearly unbelievable, young fish stocked in the spring at 8-inches will reach over 18-inches by fall, and adults often reach nearly 4-feet long and over 40-pounds. 

Recent stream sampling information is available from Iowa DNR's biological monitoring and assessment program.


Harlan, J.R., E.B. Speaker, and J. Mayhew. 1987. Iowa fish and fishing. Iowa Conservation Commission, Des Moines, Iowa. 323pp.

Loan-Wilsey, A. K., C. L. Pierce, K. L. Kane, P. D. Brown and R. L. McNeely. 2005. The Iowa Aquatic Gap Analysis Project Final Report. Iowa Cooperative Fish and Wildlife Research Unit, Iowa State University, Ames.

Photo Credit: photo courtesy of Noel M. Burkhead, copyright Noel M. Burkhead, USGS, Nonindigenous Aquatic Species.


Present in these Iowa water bodies:

Lake/Stream County Location Acres/Length
Pool 18, Mississippi River Louisa Amenities listed are for the Toolsboro Ramp. The ramp at Toolsboro is paved but the road to the ramp is gravel. There is some shore fishing along the parking area and at the outlet of Lake Odessa. Amenities vary by location in pool 18 13300.00
Pool 16, Mississippi River Scott The amenities list are for Buffalo Shores campground in Buffalo, Iowa. Amenities at other locations in Pool 16 vary by location. 13000.00
Pool 17, Mississippi River Muscatine Amenities list for Muscatine City Ramp. This ramp is located in downtown Muscatine. Amenities vary by location in Pool 17. 7580.00
Coralville Reservoir Johnson 4 miles north of Iowa City 5340.00
Lake Manawa Pottawattamie Southwest edge of Council Bluffs 784.70
Pleasant Creek Lake Linn 4 miles North of Palo 400.00
Little Wall Lake Hamilton 1 1/2 miles south of Jewell 249.00
West Nishnabotna River Fremont 121.00
Iowa River (Marshalltown to Coralville Lake) Iowa This stretch is located in Marshall, Tama, the SW corner of Benton, Iowa, and Johnson County. A popular access is at the Hwy 21 Access, which is part of the Iowa River Corridor Wildlife Area, just south of Belle Plaine. 104.00
Otter Creek Lake Tama 6 miles Northeast of Toledo 74.00
Missouri River (Sioux City to Little Sioux) Harrison Chris Larsen Park: 1280 Larsen Park Road/Sioux City, IA. Located on the Sioux City riverfront along the Missouri River. Larsen Park offers 110 acres on the Sioux City Riverfront. Managed by the City of Sioux City. 64.00
Missouri River (Council Bluffs to state line) Fremont Lake Manawa State Park: 1100 South Shore Drive/Council Bluffs, IA 51501 phone: 712-366-0220. Managed by the Iowa Department of Natural Resources Lake Manawa State Park has boat ramps on the Missouri River within the park. 61.00
Lake Smith Kossuth 3 miles north of Algona 59.00
Little Sioux River (Correctionville to Missouri R) Harrison Little Sioux Park, 2 miles SW of Correctionville, Woodberry County Conservation Board 57.00
Cedar River (La Porte City to Cedar Rapids) Linn This stretch is located in Benton and Linn County. A popular river access is in the Dudgeon Lake Wildlife Area right of Hwy 150 on the North side of Vinton. 56.00
Greenfield Lake Adair 1 mile southwest of Greenfield 56.00
Cedar River (Cedar Rapids to Moscow) Cedar This stretch is found in Linn and Cedar County. A popular access is found in Palisades State Park which is on Hwy 30 between Cedar Rapids and Mount Vernon. 55.00
Missouri River (Little Sioux to Council Bluffs) Pottawattamie Wilson Island State Recreation Area: 32801 Campground Lane/Missouri Valley, IA 51555 phone-712-642-2069. Managed by the Iowa Department of Natural Resources, Wilson Island Recreation Area has 544 acres along the Missouri River near Missouri Valley Iowa. 53.00
Hannen Lake Benton 4 miles Southwest of Blairstown 38.00
Beaver Lake Dallas 1 1/2 miles north of Dexter 34.00
Meadow Lake Adair 6 miles northeast of Greenfield 34.00
Iowa River (Coralville Lake to River Junction) Johnson This stretch is located in Johnson County. A popular access is the Tailwater East Ramp located right below the Coralville Lake Dam, East of North Liberty and Coralville. 29.00
Willow Lake Harrison 5 1/2 mile west of Woodbine 26.00
Nodaway Lake Adair 2 miles southwest of Greenfield 25.00
Central Park Lake Jones 2 miles West of Center Junction 24.00
Arrowhead Pond Pottawattamie 1 1/2 miles southeast of Neola 14.00
Ankeny Lake (DMACC) Polk Ankeny, DMACC Campus 14.00
Cocklin Fish Farm Cass 2 miles north of Griswold, for more information about this city park, contact City Hall at (712)-778-2615 8.00
Hillside West Polk Located on SE 4 mile Drive/NE 29th St. near the intersection of SE 20th St., Ankeny 1.30
Hillside East Polk Located on SE 4 mile Drive/NE 29th St. near the intersection of SE 20th St., Ankeny 1.10
Clay Pond Polk On the West Side of 3rd Ave SW near 35th St. SW in Altoona 0.80