smallmouth

Smallmouth bass, Micropterus dolomieu, is a freshwater fish in the sunfish family (Centrarchidae). Native to eastern and central North America, it has been widely introduced elsewhere and is valued as a sport fish in many regions.

The smallmouth has an elongated body, typically bronze to olive with darker vertical bands along the sides. It has a relatively small mouth; the upper jaw does not extend past the eye. The dorsal fin is two-part, with a spiny front and a softer rear.

Smallmouths inhabit clear, cool, well-oxygenated water in lakes, rivers, and large streams. They favor rocky, gravelly, or weedy substrates and structural cover such as boulders, fallen trees, and submerged vegetation. They occur from shallow bays to moderately deep water and are often more common in streams with moderate to strong currents.

They are predatory, feeding on crayfish, insect larvae, and smaller fishes, as well as amphibians and other invertebrates. Juveniles feed on zooplankton and aquatic insects. Activity is generally diurnal, with feeding peaking in spring and early summer.

Spawning occurs in spring as waters warm. Males construct and guard nests on gravel, sand, or rocky substrates, and attract females to deposit eggs. Eggs hatch after about a week, and fry are cared for by the male until they are liberated to forage on small invertebrates and then prey items.

Smallmouth bass are a popular game fish, prized for their fighting ability. Management measures include size and bag limits and seasonal protections to protect spawning fish. In some areas, introduced populations can affect local ecosystems and native species.