Lepomis macrochirus
Bluegill Sunfish

 Bluegill Sunfish

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Name:
  • Lepomis, from the Greek, "scaled gill cover"
  • macrochirus, from the Greek, "large hand"
  • Common name from bright blue chin and gill covers
  • Other common names include: Baldface, Blue Sunfish, Bluemouth Sunfish, Bream, Brim, Copperbelly, Copperhead, Coppernose Bream, Gill, Plumb Granny, Pumpkinseed, Pond Perch, Redbreasted Sunfish, Sunperch, Yellowbelly, Crapet arlequin

Taxonomy:
  • Kingdom Animalia
    • Phylum Chordata, animals with a spinal chord
    • Subphylum Vertebrata, animals with a backbone
      • Superclass Osteichthyes, bony fishes
      • Class Actinopterygii, ray-finned and spiny rayed fishes
      • Subclass Neopterygii
      • Infraclass Teleostei
        • Superorder Acanthopterygii,
        • Order Perciformes, the perch-like fishes
        • Suborder Percoidei
          • Family Centrarchidae, the Sunfishes
            • Genus Lepomis, common and eared sunfishes

Description:
  • A popular sunfish of warm, shallow waters.
  • Length
    • up to 12"
    • typically to 8", rarely more
  • Weight
    • up to 2 lbs
    • typically 1 lb, occasionally more
  • Coloration
    • appearance varies considerably among individuals, as with most sunfish
    • most are light to dark olive with emerald and brownish reflections; older fish may have purplish tinge
    • yellow or reddish below; deep red, almost dark brown breast in breeding males
    • cheeks, chin, and gill covers often bluish
    • black, flexible tip at rear of gill cover
    • dark blotch on rearward edge of soft portion of dorsal fin.
    • breeding males marked by bright blue and orange.
    • females and younger fish less colorful, often marked by dark vertical bars on their olive backs.
  • Body
    • deep, slab-sided, compressed
    • dorsal fins broadly joined, appearing as one
    • spiny, forward dorsal fin with 10 spines
    • broadly joined to soft dorsal fin with no notch
    • pectoral fins long and pointed, extending past the eye when bent in a forward position
  • Head
    • mouth rather small
    • upper jaw does not reach the front of the eye when mouth is closed

Identification:

Distribution:
  • The bluegill is Minnesota's largest and most popular sunfish. It is found in about 65% of the state's lakes and many of its slow streams, including the backwaters of the Mississippi. Rare in the Lake Superior drainage.

Habitat:
  • Warm, shallow lakes with rooted vegetation. During mid-day, they go to deeper waters of shallow lakes or beneath the shade of trees or brush.
  • Thrive in water temperature of 60º-80º F, surviving temperatures up to 85º F.

Food:
  • Young consume zooplankton, switching to aquatic insects at maturity.
  • Small mouth size limits the size of food particles ingested and almost dictates a diet of insects and similar small organisms. While insects remain the staple food item for adults, crayfish, snails, small fish, and fish eggs are also consumed. Algae and other vegetation are eaten when normal food items are scarce. Fish lice, Argulus, have been identified in bluegill stomach contents, indicating thet these fish may perform a "cleaning" function on heavily parasitized fish.
  • Young will feed in heavy weeds to avoid predators. Bluegill large enough to be of no interest to bass often swim freely in more open water, feeding heavily on tiny drifting zooplankton. This open-water feeding is especially common if Bluegill must compete with Pumpkinseed and Green sunfish, which stay in the weeds. When food is scarce, Bluegill will eat their own eggs.
  • Travel in small, loose schools while feeding, particularly in early morning or the evening, Because they feed by sight, Bluegill feed primarily during daylight.

History:
  • Minnesota Record: 2lb, 13oz, from Alice Lake (Hubbard County)
  • US Record: 4lb,12oz, from Kefone Lake, Alabama, 9 April 1950

Uses:
  • The Bluegill is sunfish of choice in America, at least to anglers. Bluegill have good table quality, good fighting ability, and are easily caught. They are eagerly sought by anglers

Reproduction:
  • Spawns from late May or through much of the summer in water temperatures of 67º to 80º. Male fans out a nest in firm-bottomed shallows, 1'- 4' deep along the shoreline, often within a colony of dozens of other nests. Nests are saucer-shaped depressions about 1'-2' in diameter over diverse substrate materials, with sand and gravel preferred. Most nests are only 2"-3" deep, and the male fish keep them fanned free of silt. A single female can deposit more than 50,000 eggs. The male then guards eggs and fry.
  • After nest construction, the ripe male selects a gravid female and entices her toward the nest with aggressive nudges and bites. Few females lay all their eggs in one nest, so each nest contains the eggs of several females. Males zealously guard the nests from all intruders and keep the eggs free from silt.
  • Sometimes Bluegill hybridize with other members of the sunfish family, Green Sunfish and Pumpkinseed.

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Last updated on 15 October 1999