Lepomis cyanellus, like the other members of the Centrarchidae family, is brightly colored. In comparison to the other members it has a wider body (more cigar shaped) and a much larger mouth. They do not grow large enough to be considered desirable “pan-fish,” because their average length is only 12.7 to 15.24 centimeters. This is sometimes due to overpopulation, which can stunt growth. Lepomis cyanellus is blue-green in color with scattered dots of black and a white to yellow belly. They have a dark spot on the soft spinous portion of the dorsal fin, and sometimes a spot on the posterior portion of their anal fin. Females have dusky colored bars on the dorsolateral portion of their body. Immature individuals lack striking color patterns, and instead are plain gray without bands. Breeding males normally have an orange tint to the anal, caudal, pelvic, and posterior dorsal fins and vivid black, orange, and white color on their anal fin. Lepomis cyanellus has palatine teeth and 28 to 29 vertebrae. Entier and Starnes (2001) state that L. cyanellus typically has “anal fin soft rays 9 to 10 (8 to 11). Pectoral fin rays 13 to 15. Gill rakers 11 to 14.” ("AWAKE Plants and Wildlife", 2003; Etnier and Starnes, 2001)
Lepomis cyanellus occurs in central North America, from the plains east of the Rocky Mountain range and west of the Appalachian mountain range, including northeastern Mexico and southeastern Canada. L. cyanellus have been introduced and established in a majority of the continental United States, with the exception of Florida and a few northeastern states. Lepomis cyanellus has been introduced to Africa, South America, Asia, and Europe as an exotic species. (Hammerson, 1993; Page and Burr, 7/2005)
Lepomis cyanellus is a species with a wide tolerance to many different aquatic conditions, one reason why they have been successfully introduced elsewhere. They prefer smaller, sluggish streams and ponds, but can also inhabit lakes with weedy shorelines and slow rivers. They tolerate both turbid and clear water. (Etnier and Starnes, 2001; Paulson and Hatch, 2004)
Lepomis cyanellus males normally build nests in sunny areas with a gravel substrate and preferably with cover, like rocks, logs, or clumps of grass. They construct depressions by forceful movement of their caudal fins in shallow water (4 to 355 cm deep). The nests are constructed in both colonies and singularly. The nests are aggressively defended by males. Spawning normally occurs 1 to 2 days after nest construction, when a male leads a female to his nest with the production of sounds. They then swim in circles above the nest before they actually spawn. Males can spawn with several females simultaneously. (Etnier and Starnes, 2001; Hammerson, 1993; Paulson and Hatch, 2004)
Spawning occurs in Lepomis cyanellus when the water rises above 21 degrees Celsius (70 degrees Fahrenheit). It is thought that L. cyanellus may produce the same number of eggs as Lepomis macrochirus, which is roughly 50,000. It takes normally 1 to 2 days for the eggs to hatch and another 5 to 7 days of protection from the male until they become independent (Parr, 2002).
Lepomis cyanellus is an aggressive species that outcompetes native species where they have been introduced. They are mainly solitary, but occur in loose aggregations, especially in breeding seasons. They are active during the day. (Etnier and Starnes, 2001)
Because L. cyanellus males lack dusky bars, it could be suggested that the bright and bold colors are means to attract females through visual cues. Males also produce sounds during mating. (Etnier and Starnes, 2001)
Green sunfish are dietary generalists. Green sunfish larvae consume various types of zooplankton and, as they grow, they expand their diets to include insect larvae and small snails. As juveniles and adults their diets expand to add small crayfish, fish eggs, insects, and small fish. It should be noted that, as competition decreases, their average prey size increases. ("AWAKE Plants and Wildlife", 2003; Etnier and Starnes, 2001; Paulson and Hatch, 2004)
Green sunfish, like other members of the family Centrarchidae, have young with a less colorful appearance; they are camouflaged to blend in with vegetation (Entier and Starnes, 2001). Their most common aquatic predators are largemouth bass (Micropterus salmoides) ; channel catfish (Ictalurus punctatus) ; flathead catfish (Pylodictis olivaris); and bullhead catfish (Ameiurus) (Paulson and Hatch, 2004; Chizinski and Pope, 2003). (Chizinski and Pope, 2003; Paulson and Hatch, 2004)
Lepomis cyanellus is both a predator and prey, therefore it is a means of transferring energy through the food chain. Since it is such an aggressive species it commonly out competes native fish and affects populations of other aquatic organisms such as crayfish and freshwater mussels. (Etnier and Starnes, 2001; HAAG, et al., 1998)
Although L. cyanellus is barely suitable as a "pan-fish," they can be exciting to catch. They have a tendency to attack almost any bait and provide a tough fight for anglers, given their size. (Etnier and Starnes, 2001; Paulson and Hatch, 2004)
Lepomis cyanellus is not listed endangered or threatened either nationally or internationally. They are common and abundant throughout their range.
Hybridization, which is reproduction between two different species, is very common in L. cyanellus. Hybrids tend to be mostly males and grow faster than either of the parent species. Bluegill (Lepomis macrochirus) and longear sunfish (Lepomis megalotis) are common species that Lepomis cyanellus crossbreeds with. Lepomis megalotis and L. cyanellus hybrids are commonly known as “hybrid bluegills”. (Entier and Starnes, 2001; www.Kentuckyawake.org) ("AWAKE Plants and Wildlife", 2003; Etnier and Starnes, 2001)
ETYMOLOGY: “Lepomis” means scaled operculum and “cyanellus” means blue. (Etnier and Starnes, 2001)
Tanya Dewey (editor), Animal Diversity Web.
Emily Clemons (author), Eastern Kentucky University, Sherry Harrel (editor, instructor), Eastern Kentucky University.
2003. "AWAKE Plants and Wildlife" (On-line). Accessed October 27, 2005 at http://www.kentuckyawake.org/templates/plantsWildlife/lifehistory.cfm?instanceID=18954.
Chizinski, C., K. Pope. 2003. Importance of food Ration and Water Temperature on Growth of Juvenile Green Sunfish (Lepomis cyanellus). The Texas Journal of Science, 55/3: 263.
Etnier, D., W. Starnes. 2001. The Fishes of Tennessee. Knoxville: The University of Tennessee Press.
HAAG, W., M. WARREN, M. SHILLINGSFORDa. 1998. Host Fishes and Host-attracting Behavior of Lampsilis altilis and Villosa vibex. The American Midland Naturalist, 141/1: 149-157. Accessed October 29, 2005 at http://www.bioone.org.libproxy.eku.edu/bioone/?request=get-abstract&issn=0003-0031&volume=141&issue=01&page=0149.
Hammerson, G. 1993. "Lepomis cyanellus" (On-line). NatureServe Explorer. Accessed October 27, 2005 at https://ekumail.eku.edu/exchweb/bin/redir.asp?URL=http://www.natureserve.org/explorer/servlet/NatureServe?searchName=Lepomis%2520cyanellus.
Page, L., . Burr. 7/2005. "Lepomis cyanellus, Green Sunfish" (On-line). FishBase. Accessed October 27, 2005 at http://fishbase.org/Summary/speciesSummary.php?ID=3371&genusname=Lepomis&speciesname=cyanellus.
Paulson, N., J. Hatch. 2004. "Minnesota Depatment of Natural Resources' MinnAqua Aquatic Program" (On-line). Accessed October 27, 2005 at https://ekumail.eku.edu/exchweb/bin/redir.asp?URL=http://www.gen.umn.edu/research/fish/fishes/green_sunfish.html%23reproduction.