What's In a Name?
Smallmouth bass: named for the size of the mouth compared to the largemouth bass.

Micropterus (my-crop´-ter-us) means "small or short fin" in Greek; a reference to the damaged fin on the original specimen.
dolomieui (doe-loe-mew´-ee) named after Dieudonne' de Dolomieu, a French geologist and friend of Lecepede, who named the species.

How Big Do They Get?
How Long Do They Live?
In general smallmouth do not grow as fast or get as big as largemouth bass. Still, this species often reaches 300 mm (12 in) or more, in many Minnesota lakes and streams. Very rarely it reaches 500 mm (20 in). Many anglers catch smallmouth that weigh 0.9-1.8 kg (2-4 lbs) in Minnesota. The state record is 3.6 kg (8 lbs). This fish was caught in West Battle Lake in Otter Tail County. Smallmouth frequently reach 7-10 years old, and on rare occasions may reach the age of 15 years.

What Eats Them?
Larval and young-of-the-year smallmouth bass are preyed upon by larger bass, yellow perch, sunfishes, and northern pike. Other animals that probably eat young smallmouth include herons, frogs, and some snakes. As adults, smallmouth bass are eaten only by larger bass, northern pike, and musky. Humans are the main predator of adults.

How Do They Reproduce?
In Minnesota, smallmouth bass spawn mostly from the middle of May through the end of June when water temperature exceeds 15.5° C (about 60° F). We have records of spawning as late as early August, however. The male selects the spawning site and sweeps out a nest up to 1 m (3 ft) in diameter with his tail. The nest normally ends up in a gravel bed, often next to a log, boulder, or other obstruction in 1-3m (about 3-10 ft) of water. Once the nest is built, the male defends it aggressively from both male and female smallmouth. A female that wants to spawn has to be persistent. She may be helped somewhat by her change in appearance. The dark mottling on her body becomes more noticeable as the background color fades, and this may help communicate to the male that the female is ready. Once in the nest, both fish lay beside each other and release their eggs and sperm. This spawning act can be repeated every 30 seconds or so for up to 2 hours. When the female is done laying the eggs, she leaves the nest and the male stays behind to protect the eggs from predators. Both males and females usually spawn with more than one partner. A single female may lay 2,000-14,000 eggs, depending on her size.

The eggs (embryos actually) hatch in about one week and the free-living embryos continue to develop in the nest for about one more week. After that, they swim up into the water column and begin to feed. In lakes, the male smallmouth may continue to protect the larvae for a short time even after they swim up.

Conservation and Management
One of the top three warm-water sportfish in Minnesota (largemouth and northern pike are the other two). This species has been planted in many lakes and streams over the years. The principal management strategy is to protect it during the early spawning season and limit its daily catch.