Bluegill (Lepomis macrochirus)

Bluegill

At times easily caught by novice and experienced anglers alike, bluegills are among the most popular panfish species in North America. This notoriety is the result of their vast distribution, spunky fight, and excellent taste.

Commonly referred to as “bream,” bluegills are the most widely distributed panfish and are found with, or in similar places as, such companion and related species as redbreast sunfish, green sunfish, pumpkinseeds, shellcrackers, and longear sunfish, all of which are similar in configuration but different in appearance.

Despite their abundance and popularity, bluegills are not heavily targeted in some waters and are thus underutilized. Bluegills are so prolific that their populations can grow beyond the carrying capacity of the water, and as a result many become stunted; these stunted fish are regarded as pests, and waters containing them must often be drained and restocked. There are three subspecies of bluegills in existence, although stocking has intermingled populations and subspecies.

Identification

The bluegill has a significantly compressed oval or roundish body, a small mouth, and a small head, qualities typical of members of the sunfish family. The pectoral fins are pointed.

Its coloring varies greatly from lake to lake, ranging from olive, dark blue, or bluish purple to dappled yellow and green on the sides with an overall blue cast; some fish, particularly those found in quarry holes, may actually be clear and colorless. Ordinarily, there are six to eight vertical bars on the sides, and these may or may not be prominent.

The gill cover extends to create a wide black flap, faint in color on the young, which is not surrounded by a lighter border as in other sunfish. Dark blue streaks are found on the lower cheeks between the chin and the gill cover, and often there is a dark mark at the bottom of the anal fin. The breeding male is more vividly colored, possessing a blue head and back, a bright orange breast and belly, and black pelvic fins.

Size/Age

These fish range from 4 to 12 inches in length, averaging 8 inches and reaching a maximum length of 16.25 inches. The largest bluegill ever caught was a 4-pound, 12-ounce specimen taken in 1950. The growth of the bluegill varies so much that estimates of age as it relates to size are at best inexact. Bluegills are estimated to live for 10 years.

Life history/Behavior

The age of sexual maturity varies with environment and locale, although most bluegills reach spawning age when 2 or 3 years old. Spawning occurs between April and September, starting when water temperatures are around 70°F.

The males build shallow, round nests in water up to 6 feet deep over sandy or muddy bottoms. These nests occur in colonies of up to 500 along the shoreline, densely concentrated and easily spotted by anglers. Females may lay between 2,000 and 63,000 eggs, which hatch 30 to 35 hours after fertilization.

It is common for fish to spawn many times, with a particular fish laying eggs in several nests and a single nest containing eggs from more than one female. Males guard the eggs throughout the incubation period and stay to protect the hatched young. Having reached lengths of 1⁄4 to 1⁄3 inch, the young leave their nests for deeper waters. Bluegills travel in small schools, typically made up of similar-size individuals.

Food and feeding habits

A variety of small organisms serves as food for bluegills, including insects, crayfish, fish eggs, small minnows, snails, worms, and sometimes even plant material. The young feed mostly on crustaceans, insects, and worms. Adults will feed at different depths, depending on temperature, so they obtain food on the bottom, as well as on the surface. Active mostly at dusk and dawn, the larger bluegills move inshore in the morning and the evening to feed, staying in deeper water during the day.

Other Names

bream, brim, sun perch, blue perch, blue sunfish, copperbelly, blue bream, copperhead bream, redbreasted bream, bluegill sunfish, roach.

Distribution

Native to approximately the eastern half of the United States, the bluegill’s range extends southward from the St. Lawrence River through the Great Lakes and the Mississippi River basin, eastward from New York to Minnesota and draining south from the Cape Fear River in Virginia to the Río Grande in Texas, including states as far east as Florida and as far west as New Mexico. Also found in a small portion of northeastern Mexico, the bluegill has been widely introduced elsewhere in North America, as well as in Europe, South Africa, Asia, South America, and Oceania.

Habitat

Although mainly lake fish, bluegills inhabit sluggish streams and rivers, vegetated lakes and ponds, swamps, and pools of creeks. They prefer quiet waters and may hold in extremely shallow areas, especially early in the season and during spawning time, although when the surface and shallow water temperature is warm in the summer, they may go as deep as 30 or more feet. They occupy the same habitat as their larger relative the largemouth bass.