Bluegill

Lepomis macrochirus

Type: freshwater

Bluegill

Physical Characteristics

Deep-bodied, laterally compressed sunfish with a small mouth and a distinctive dark spot on the posterior edge of the opercle (ear flap). Coloration is typically olive-green on the back with yellowish-orange hues on the belly, often featuring 5-9 vertical dark bars on the sides. The dorsal fin has spines followed by a soft lobe with a dark blotch at the base.

Habitat & Distribution

Native to North America, they are found in lakes, ponds, slow-moving rivers, and wetlands with abundant aquatic vegetation and structures like fallen logs or docks for cover.

Size & Weight

Adults usually range from 4 to 12 inches (10-30 cm) and weigh between 0.25 to 2 pounds. The world record is 4 pounds 12 ounces.

Similar Looking Species

Pumpkinseed (distinguished by a red or orange spot on the opercle flap and wavy blue lines on cheeks) and Green Sunfish (which has a much larger mouth and turquoise markings on the face).

Ecological Role

Serves as both an important mid-level predator of aquatic invertebrates and a vital prey source for larger predators like largemouth bass, pike, and herons.

Diet

Omnivorous opportunistic feeder that consumes aquatic insects, small crustaceans, snails, and occasionally small fish or plant matter.

Behavior

Highly social fish that frequently form large schools. They are diurnal, being most active during the early morning and late evening, often congregating near submerged structures.

Reproduction

Males construct circular nests in sandy or gravelly shallow water, often in large colonies. Spawning occurs in spring and summer. Males protect the eggs and fry until they can swim on their own.

Conservation Status

Least Concern (IUCN); populations are stable and widespread due to successful introductions and high reproductive rates.

Identification Tips

Look for the solid dark blue or black 'ear' flap without any red or white margins, and a dark blotch at the posterior base of the soft dorsal fin.

Interesting Facts

Bluegill can live for 8 to 11 years. They are known for their ability to adjust their feeding habits and have become an invasive species in some parts of Asia and Europe due to their high adaptability.

Identified on: 6/18/2026

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