Redbreast Sunfish, Lepomis auritus
Redbreast Sunfish, Lepomis auritus, Female. Fish caught from the Eno River, North Carolina, October 2013. Length: 13 cm (5.1 inches). Catch, photograph and identification courtesy of Ben Cantrell, San Diego, California.
Redbreast Sunfish, Lepomis auritus, Male. Fish caught from the Julington Pond, Jacksonville, Florida, July 2016. Length: 20 cm (7.9 inches). Catch, photograph and identification courtesy of Chris Moore, Peoria, Arizona.
The Redbreast Sunfish, Lepomis auritus, is a member of the Sunfish or Centrarchidae Family, that is also known as the Redbreast Bream and the Yellowbelly Sunfish, and in Mexico as mojarra oreja azul. Globally, there are thirteen species in the genus Lepomis, of which seven are found in the streams, rivers, lakes, and ponds of Mexico’s freshwater systems.
The Redbreast Sunfish has a very deep and moderately compressed body. They are blue-green dorsally transitioning to yellow ventrally. They are dimorphic with females having yellow bellies and males having orange or rusty bellies. The upper lobe of the caudal fin and soft dorsal fin have yellow margins that are red in breeding males. The gill cover has a long opercle flap that can be over 2.5 cm (1.0 inch) in length and narrow in width, being not wider than the eye and has bright blue vermiculations. Juveniles have 12 vertical bars on their sides. They have a short head and a very small terminal mouth. Their anal fin has 9 or 10 rays; their caudal fin is slightly forked and rounded; their dorsal fin is continuous with 10 or 11 spines and 10 to 12 rays; and, their pectoral fin has 13 to 15 rays. They have 9 to 12 gill rakers. They are covered with small scales. Their lateral line arches upward anteriorly.
The Redbreast Sunfish is found in vegetated areas near the edge of lakes and in rocky pools. They reach a maximum of 30 cm (12 inches) in length and 1.0 kg (2 lbs 5 oz) in weight. As of January 1, 2023, the International Game Fish Association world record stood at 0.79 kg (1 lb 12 oz), with the fish caught in the Suwannee River, Florida in May, 1984. They thrive in freshwater lakes, streams and rivers with shelter and structure. They prefer water temperatures between 16oC (60oF) and 27oC (80oF). They are opportunistic feeders that consume aquatic insects, insect larvae, crayfish, snails, other small invertebrates and small fish. In turn they are preyed upon by Black and White Crappie, Largemouth Bass and Smallmouth Bass as well as sea birds and otters, raccoons, and turtles. Reproduction is oviparious and polygynandrous (promiscuous) and occurs continually when water temperatures are in excess of 16oC (62oF). During this period males become highly territorial and very aggressive. They build highly visible nests in very shallow sand or gravel substrate. Each female, based on size, will deposit between 1,000 and 100,000 eggs into the nest. Fertilization is external and males remain on the nest for 5 days until the eggs hatch and the young may remain schooled up on the nest for several weeks before scattering. Young fish feed on plankton, but as they grow their diet shifts to aquatic insects and insect larvae. With high reproductive rates, low predation, and low fishing pressure, Redbreast Sunfish population growth can be explosive. They have a life spans of up to seven years.
The Redbreast Sunfish is a native to eastern North America and can be found in the majority of rivers that drain into the Atlantic Ocean. They have been widely introduced as a game fish which has included Northeast Mexico in the States of Coahuila, Nuevo León and Tamaulipas.
The Redbreast Sunfish can be easily confused with the Green Sunfish, Lepomis cyanellus, (larger mouth and long gill rakers) and the Longear Sunfish, Lepomis megalotis, (deeper body depth; opercule flap narrower than the eye diameter).
From a conservation perspective, the Redbreast Sunfish is currently considered to be of Least Concern with stable, widely distributed populations. They have been raised in fish hatcheries and introduced extensively throughout the southern United States and into northern Mexico and other countries as a sportsfish. They quickly become a highly invasive pest causing overcrowding conditions and destroying native populations. They are a popular recreational angler foe on light tackle and flyrods. They are also considered to be an excellent food fish. They are also utilized by the aquarium trade.