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Smallmouth Bass

Smallmouth Bass

Smallmouth bass are among Iowa's most important gamefish and are considered the top predator in many Iowa rivers.

Physical Characteristics:
  • These slender, streamlined fish have a moderately large mouth where the upper jaw reaches about to the rear margin of the eye in adults.
  • Their body is golden green on the sides and back with faint wavy olive blotches evenly spaced along the sides.
  • Five olive-green bars radiate backward from the eye, and one forward to the end of the snout.
  • Young smallmouth have a distinctive tri-colored tail fin with a black vertical bar separating the yellowish fin base.

What to know

Habitat Distribution

  • Smallmouth prefer clear water with hard bottoms and are rarely found far from rock or gravel.
  • They thrive in free-flowing sections of streams and rivers with riffle-pool habitat and moderate to high amounts of rock.

Key Locations

  • Smallmouth bass are widespread throughout Iowa, with populations found in small to medium central and northeast Iowa rivers, larger rivers such as the Cedar, Des Moines and Mississippi, as well as some natural lakes in northwest Iowa.
  • The northeastern two-thirds of Iowa contains the best populations, with the highest concentrations in northeast Iowa's clear rivers and streams.
  • They're also found in Spirit Lake, the Okoboji chain, and other natural lakes.
  • In northeast Iowa rivers like the Upper Iowa, Turkey, Volga, Yellow, Wapsipinicon, Cedar, Shell Rock, and Maquoketa.
  • For lake fishing at West Okoboji and Spirit Lake.

Specific Spots

  • Target areas with current breaks, rocky shorelines, riprap, bridge abutments, and underwater structure.
  • Focus on rocky habitat, log-fall areas, and deep holes above riffles.
  • Target rocky points and flats in 4-12 feet during pre-spawn, work submerged rock reefs in summer, and fish shallow rock reefs in 10-15 feet during fall.
  • Urban areas near cities often provide excellent fishing below dams and along riprap banks.

Smallmouth Bass FAQ

Answers from onWater's species guide.

What are the best lures and bait for Smallmouth Bass in Iowa?

Top lure choices include crayfish-colored crankbaits, spinnerbaits, and rattling crankbaits in turbid water. Use chartreuse, brown, and black colors or lures with silver/gold reflecting flakes in low-light conditions.

When is the best time to fish for Smallmouth Bass in Iowa?

April offers outstanding opportunities. However, avoid fishing during spawning in early May when water exceeds 60 degrees. In hot July-August weather, smaller fish are active in 1-2 feet of water above and below rock riffles, while larger bass move to deeper structures.

How do you catch Smallmouth Bass in Iowa?

Work spinnerbaits 1-2 feet below surface and shallow-running minnow crankbaits near shallow structures. Crankbaits that hug bottom in 4-5 feet or lead-heads bounced along bottom work best for quality fish. Cast parallel to rock faces rather than perpendicular to maximize effectiveness.

What do Smallmouth Bass eat?

Smallmouth are omnivorous predators that sight feed aggressively on invertebrates, minnows, shiners, fish, crustaceans, and larger aquatic and terrestrial insects. Crayfish make up 30% of their diet when available, with forage fish comprising 40% of stomach samples and insects 20%.

Where do Smallmouth Bass live in Iowa?

Smallmouth prefer clear water with hard bottoms and are rarely found far from rock or gravel. They thrive in free-flowing sections of streams and rivers with riffle-pool habitat and moderate to high amounts of rock.

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