freshwater
Smallmouth Bass
Micropterus dolomieu
Body is robust, torpedo-shaped, and compressed laterally. Coloration is typically bronze or olive-green on the back, fading to yellowish-white on the belly, with dark vertical bars on the sides rather than a horizontal stripe.…
- Habitat
- Found in clear, cool streams, rivers, and deep, clear la…
- Size & weight
- Typically 12 to 20 inches in length and weighing 1 to 4…
- Diet
- Carnivorous, feeding on insects, crayfish, and smaller f…
Identified More freshwater →
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Physical characteristics
Body is robust, torpedo-shaped, and compressed laterally. Coloration is typically bronze or olive-green on the back, fading to yellowish-white on the belly, with dark vertical bars on the sides rather than a horizontal stripe. The upper jaw does not extend past the back of the eye, distinguishing it from the largemouth bass.
Habitat & distribution
Found in clear, cool streams, rivers, and deep, clear lakes with gravel, rock, or sandy bottoms. Native to North America, particularly the Great Lakes, upper and middle Mississippi River basins, and the St. Lawrence River system.
Behavior
Generally solitary outside of the spawning season. Most active during dawn and dusk (crepuscular) and prefers structured environments near rocks or submerged logs.
Diet
Carnivorous, feeding on insects, crayfish, and smaller fish. They are opportunistic ambush predators.
Reproduction
Spawning occurs in the spring when water temperatures reach 60 to 65 degrees Fahrenheit. Males build circular nests in gravelly areas, court females, and fiercely guard the eggs and fry until they disperse.
Ecological role
Acts as an apex or mid-level apex predator in freshwater ecosystems, helping to regulate populations of smaller forage fish, insects, and crustaceans.
Similar species
Largemouth Bass (Micropterus salmoides), which has a jaw extending past the rear margin of the eye and a distinct dark horizontal stripe along the body instead of vertical bars.
Identification tips
Look for the red eyes, bronze-to-olive coloration, vertical dark bars on the flanks, and the upper jaw ending directly beneath the eye.
Interesting facts
Smallmouth bass are exceptionally strong fighters relative to their size, making them one of the most popular sport fish in North America. The male smallmouth bass is solely responsible for guarding the nest and protecting the developing fry from predators.