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What are the Characteristics of the Bluegill?

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Bluegills (Lepomis macrochirus) make up a species of family Centrarchidae fish. They are mostly freshwater creatures, but also occasionally go into water that has a little bit of salinity. Bluegills come from North America and don't appear naturally anywhere else on earth. They're fixtures in the waters of many states, including Minnesota and Texas.

Physical Characteristics

As sunfish or "sunnies," bluegills possess the trademark flattened and high physiques of the family. Mature specimens are usually around six inches long, although some individuals are as lengthy as one foot. The top parts of their bodies are usually blackish-blue, greenish-brown, yellowish-green or deep green, while the rest is generally pale yellow. The edges of their oval outlines often feature vertical banding. Their cheeks have elements of dark purple or blue coloration, the origin of their common name. Bluegills' mouths are particularly memorable due to being extremely tiny in size.


Bluegills usually establish themselves in rugged and sluggish creeks, lagoons, marshes, lakes, reservoirs and ponds. They have penchants for relatively silent waters. Bodies of water with extensive water plants can sometimes be troubling for the species, as those occasionally disturb their eating habits.


Bluegills consume lots of little creatures that slide easily into their wee mouths. Their menus are heavy in meat. Some typical foods that make up their diets are caterpillars, worms, spiders, snails, larvae, crayfish, water insects and crustaceans. Bluegills also routinely dine on fellow fish, along with their eggs. They sometimes feed on plants, too, specifically algae. These fish have massive appetites and definitely aren't picky eaters. They eat most of what they are capable of acquiring.


Bluegill reproduction takes place at the end of the spring and start of the summer. The males are in charge of constructing the nests, which they protect fiercely. They frequently establish their nests in close proximity to those of fellow bluegills. When they're inside their nests, they lure females in by making guttural sounds. Male and female bluegills massage their stomachs against each other, and then give off eggs and sperm. Once female specimens deposit their eggs, the males closely watch over them. Males and females are easy to tell apart in times of reproduction. The males' heads and blacks turn bluish, and their undersides take on an attractive and vivid reddish-orange coloration.


Bluegills are at their busiest around daybreak. In the daytime, they remain low key. At night, they travel to shallower depths. They move about in schools, which typically are made up of between 10 and 20 individuals.