Smallmouth Bass

Smallmouth Bass

Characteristics

golden green sides and back with faint, wavy olive blotches along the sides, 5 olive-green bars radiate back from the red eye and 1 radiates forward; spiny and soft portions of dorsal fin broadly connected; fish over 3-4 pounds are trophy-sized

Distribution

Smallmouth Bass Distribution

northeastern 2/3 state in clear rivers, streams and some lakes; most abundant in northeast Iowa

Foods

fish, crustaceans, larger insects

State Record

7 pounds, 12 ounces - West Okoboji Lake, Dickinson County, September 1990 - Rick Gray, Dickinson, Iowa

Expert Tip

light spinning gear using crayfish colored crankbaits can produce hot smallmouth action!

Details

The smallmouth bass is primarily an inhabitant of swift flowing, less turbid waters in rivers and smaller streams. Smallmouth bass are most abundant and widely distributed in the rivers of central and eastern Iowa, but they are occasionally found in impoundments and natural lakes that contain suitable habitat. They are common to abundant in smaller tributary streams during spawning in late spring and are taken occasionally in the Mississippi. Since impoundment of this stream for navigation, smallmouth numbers have decreased.

The smallmouth bass is a slender, streamlined-shaped fish with a moderately large mouth, where the upper jaw reaches about to the rear margin of the eye in adults. Spiny and soft parts of the dorsal fin are broadly connected with only a shallow notch between the lobes. Body color is golden green on the sides and back with faint wavy olive blotches evenly spaced along the sides. There are five olive green bars radiating backward from the eye, and one forward to the end of the snout. The tail fin in young smallmouth is distinctly tri-colored with a black vertical bar separating the yellowish fin base. Pyloric caeca are not forked in contrast to forked pyloric caeca in the closely related largemouth bass.

Smallmouth bass are omnivorous in the food items that they consume. In the larger cool, clear interior streams of northeast Iowa smallmouth bass is the dominant predator, feeding mostly on fish, crustaceans and larger aquatic and terrestrial insects. Food habit studies have revealed that forage fish were present in 40 percent of the stomach samples, crayfish in 30 percent and insects in 20 percent. Where crayfish are abundant, they frequently comprise over two-thirds of the food. Newly hatched smallmouth consume copepods and cladocerans but begin to forage on insects when about one-half inch long. By the time fingerling smallmouth bass are 1 1/2 inches in length, insects and small fish comprise the bulk of the diet.

Smallmouth bass spawn in Iowa during the early part of May as water temperatures exceed 60' F. Preparatory to the spawning ritual, parent spawners move up larger streams, eventually reaching small tributaries where the actual spawning occurs. Male fish construct a saucer-shaped nest on the gravel, coarse sand or rock bottom by sweeping its tail over the substrate. The 14 to 25 inch diameter nest is located in quiet water near the shoreline downstream from a boulder or other natural structure that deflects and slows the current force.

The ripe male bass selects a gravid female after nest construction and nudges her toward the nest in a series of aggressive body contacts and bites. If the female refuses the nest, the male becomes more aggressive until the female is finally physically driven over the depression. Both fish lie side by side, facing the same direction during egg emission as the female vibrates her body by muscle action. The male releases milt for fertilization as the eggs are deposited. The female leaves the nest territory after spawning but may return later to the same nest or another if she has latent egg development. Male fish usually ripen again after a short period of time. Male fish protect the nest from predation and fan the eggs free of silt until the sac fry emerge in 3 to 5 days, depending on water temperature. Re-nesting is quite common for smallmouth, particularly when early nests are destroyed by natural events such as a flood.

The number of eggs laid by a female smallmouth bass varies greatly depending on body size. Average fecundity is 7,000 to 8,000 eggs per pound of body weight. Newly hatched sac fry swim over the nest in a school for about 6 to 15 days, moving sluggishly until all the nourishment in the yolk sac is consumed. The young fry are about one-half inch long when the yolk sac is absorbed, and they leave the nest to feed on small crustaceans and copepods.

Smallmouth bass growth varies with the amount of food eaten and water temperature. Most smallmouth bass in Iowa reach 3 to 5 inches by the first autumn, 6 to 7 inches in the second year, and 9 to 10 inches the third year. Smallmouth sexually mature in the second or third year of life, but where food is scarce or water is relatively cool in all seasons, maturation may not occur until the third or fourth year. Maximum weights of 6 or 7 pounds have been reported in Iowa, but fish over 3 to 4 pounds are trophy sized.


Return
Present in these Iowa water bodies:
Lake/Stream County Location Acres/Length
Pool 9, Mississippi River Allamakee River Mile 647.9 at Lynxville, WI upstream to River Mile 679.2 at Genoa WI. 35169.00
Pool 19, Mississippi River Lee Amenities listed are at City of Ft. Madison boat ramp. Amenities vary by location in Pool 19 33500.00
Pool 13, Mississippi River Clinton Between Bellevue and Clinton, Iowa. Pool 13 Starts at River Mile 556.7 28117.00
Pool 11, Mississippi River Dubuque River Mile 583 at Dubuque, IA upstream to River Mile 615 at Guttenberg, IA. 19875.00
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 12, Mississippi River Jackson Between Dubuque and Bellevue, Iowa 12349.00
Pool 14, Mississippi River Scott Located between Clinton and Davenport, starts at River Mile 522.5 10291.00
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
Big Spirit Lake Dickinson One mile North of Spirit Lake 5684.00
Coralville Reservoir Johnson 4 miles north of Iowa City 5280.00
West Okoboji Lake Dickinson northwest edge of Arnolds Park 3847.00
Pool 15, Mississippi River Scott Between Davenport, Iowa and Rock Island Illinois. Starts at River Mile 482.9 3626.90
East Okoboji Lake Dickinson east edge of Okoboji 1835.00
Big Creek Lake Polk 2 miles north of Polk City 814.00
Big Lake (Lansing) Allamakee 3 m N Lansing 800.00
Twelve Mile Creek Lake Union 4 miles east of Creston 635.00
Lake Delhi Delaware 3m W Delhi 448.00
Frenchtown Lake Clayton 270.00
Center Lake Dickinson 2 miles west, 1/2 miles south of Spirit Lake 220.00
New Albin Big Lake Allamakee 200.00
Nashua Impoundment (Cedar Lake) Chickasaw Located on the east edge of Nashua. 200.00
Minnewashta Lake Dickinson 1/2 mile south of Arnolds Park 118.00
Middle Raccoon River (above Van Meter) Dallas The best access is the hard surface ramp below the dam in the city of Redfield. 110.00
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
Sand Lake Marshall On the Northeast edge of Marshalltown 95.00
Turkey River (above Clermont) Fayette This section of river includes the headwaters in Howard county and flows through Winneshiek and Fayette Counties. A popular access is at Vernon Springs Park just 2.5 miles southwest of Cresco. 89.00
Maquoketa River (below Monticello) Jackson 82.00
Volga River Clayton This stretch includes the headwaters in Fayette County and flows through Clayton County where it empties into the Turkey River just west of Garber. 81.00
Upper Iowa River (above Decorah) Winneshiek This stretch is found in Howard and Winneshiek County. A popular access is found in Kendallville Park and Campground off of Hwy 139 about 8 miles northeast of Cresco. 79.00
Cedar River (Nashua to La Porte City) Black Hawk North Cedar Park located on the north side of Highway 188 east of Plainfield is an excellent hard surface boat launch. 77.00
Wapsipinicon River (Tripoli to Troy Mills) Buchanan Most angling occurs below Sweet Marsh Reservoir or Highway 3 and south to Troy Mills. 73.00
Winnebago River Floyd Located in Winnebago, Hancock, Worth, Cerro Gordo, and Floyd Counties. A good access point is East Park in Mason City. It offers excellent shore access to the river and a good starting point for a float trip down to the Averydale Access. 72.00
West Fork Cedar River Black Hawk Best access locations are west of Highway 14 below the Big Marsh Wildlife Area in Butler County. 68.00
Maquoketa River (above Monticello) Delaware Access points begin below the dam at Backbone State Park. 68.00
Iowa River (Iowa Falls to Marshalltown) Marshall This stretch is located in Hardin and Marshall County. A popular access is located in Pine Lake State Park, just east of Eldora on County Road S56. 66.00
Wapsipinicon River (Oxford Junct to Mississippi R) Scott Wapsi River Environmental Education Center : 31555 52nd Avenue, Dixon, Iowa 52745. Northeast of Dixon along the Wapsi River. And Sherman Park across the River in Clinton County 66.00
Turkey River (below Clermont) Clayton This stretch is found in Fayette and Clayton County. A popular scenic and historical area is the Motor Mill Access about 8 miles southeast of Elkader on Galaxy Road. 65.00
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
Cedar River (above Nashua) Floyd This stretch is found in Chickasaw, Floyd, and Mitchell County. A popular multi-use location is the Charles City Whitewater Park in downtown Charles City on Hwy 14. 63.00
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
South Skunk River (Cambridge to Pella) Marion A hard surface access is located South of Cambridge on the north side of Highway 210, 3 miles east of Interstate 35. 58.00
Shell Rock River (above Greene) Floyd Located in Worth, Cerro Gordo, and Floyd Counties. A popular access point is Wilkinson Pioneer Park located at the end of CR B20 in Rock Falls. This park is the start of the Shellrock River Greenbelt and Preserve featuring 7.5 mi. of scenic bluffs. 58.00
Upper Iowa River (below Decorah) Allamakee This stretch includes Winneshiek and Allamakee County. A popular access is at Lower Dam about 11 miles northeast of Decorah. 57.00
Des Moines River (Stratford to Saylorville Lake) Polk The Highway 30 Access is in the middle of this river section and is located 3 miles west of Boone on the north side of Highway 30. 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
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
Rock River Sioux 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
Wapsipinicon River (Troy Mills to Oxford Junction) Jones This stretch is located in Linn and Jones County. A popular access on this stretch is in Pinicon Ridge Park, just off Hwy 13 by Central City. 53.00
East Fork Des Moines (Algona to Humboldt) Humboldt 52.00
Des Moines River (Saylorville to Red Rock) Marion A mid-section access point for this stretch of river is at the Pleasant Hill Boat Ramp. This ramp is located on SE Vandalia Drive immediately east of Highway 65. 50.00
Iowa River (above Iowa Falls) Hardin 49.00
West Fork Des Moines (Emmetsburg to Humboldt) Humboldt 48.00
Lidtke Impoundment Howard This impoundment is adjacent to Lidtke Mill and located on the Upper Iowa River just north of Lime Springs. 43.40
Prairie Park Fishery Linn 1.5 miles SSE of Cargill on Otis Road, along the Cedar River in Cedar Rapids 42.00
Charles City Impoundment Floyd Located on the Cedar River in the middle of Charles City. 40.90
Lylah's Marsh County Park Howard Located 3.5 miles northwest of Elma. 32.30
North Raccoon River (Perry to Van Meter) Dallas A mid-section access point for this section of river is at the Highway 44 Access 4 miles west of Dallas Center. 31.00
Elkader Impoundment Clayton Elkader 30.40
South Skunk River (Story City to Cambridge) Story A mid-section access is the Sleepy Hollow Access off of West Riverside Road just east of Highway 69 on the north side of Ames. 30.00
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
Gimmel Lake Allamakee 28.00
Shell Rock River (Greene to Shell Rock) Butler The city of Greene is located at the junction of Highway 14 and County Rd. C13. 26.00
Mohawk Park Lake Linn East side of the Cedar River off J Ave. 26.00
Yellow River Allamakee T96N, R6W, S3 to T96N, R4W, S24 25.00
Martelle Lake Allamakee 24.00
Dakins Lake Story 2m NE Zearing 20.00
Otranto Impoundment Mitchell Located 0.25 miles east of Otranto, Iowa on the Cedar River. 19.00
Seminole Valley Park Lakes Linn Along the Cedar River in Northwest Cedar Rapids 12.00
Paint Creek Allamakee Located in Yellow River State Forest, 3 miles west of Harpers Ferry off of State Forest Road or CR B25. 11.00
Scharnberg Pond Clay 3m E Everly 10.00
Bloody Run Creek Clayton Located 2 miles west of Marquette off of Highway 18. 6.50
Bear Creek Fayette Located 6 miles southeast of Fayette off of Kornhill Road or CR C24. Access from 128th Street. 1.20
Tete des Morts River Jackson Located near St. Donatus. T87N, R3E, S4 1.10
Turkey River Clayton Located 6 miles northwest of Elkader at Big Spring Hatchery. 1.00
Mink Creek Fayette Located on private property 1.5 miles north of Wadena, access on Bighorn Road. 0.90