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Bass is the common name for a number of popular freshwater and saltwater fish, which include the wide mouth bass, the striped bass, groupers, jewfish, and wreckfish, which are some of the finest sports and food fish in the world.

Fish known as bass actually belong to different families and are distributed worldwide in tropical and temperate waters.

The freshwater family Centrarchidae includes the black basses, crappies, and sunfish. All species have plump, oval bodies with rough scales with a comblike edge. There are two dorsal fins which are connected, the first fin with thick spines. Heavy spines are also found in the anal fin. Freshwater basses include the predatory largemouth bass, Micropterus salmoides, which is generally found in shallow waters with plenty of vegetation such as slow moving streams with muddy bottoms and lakes. The largemouth bass is widespread in the United States and southern Canada and is an important sport fish. The average size of largemouth bass varies; bass from southern regions are heavier than those from the north. In southern Georgia a specimen was caught by rod and reel weighing 22.25 lb (10 kg). The species spawns in late March in the south but in June in the north. Largemouth bass demonstrate characteristic parental care of the young. When females are about to lay their eggs males will prepare the nest. After a female has laid her eggs, the male will deposit sperm (milt) over them. He will guard the nest from potential enemies. In the course of their development the eggs are fanned to aerate them and to keep off mud and silt. After the eggs develop into fry the male guards the young for several weeks.

The largemouth bass, so called because of its large mouth compared to the other basses, is greenish with a lateral stripe on each side, the color depending on size, and water temperature and chemistry.

The smallmouth bass, M. dolomieui, is found in North America farther north than the largemouth bass. The smallmouth bass is found in cold, moving water, and not generally on muddy bottoms. It is a smaller species than the largemouth bass, on average weighing under a pound. It is somewhat more aggressive and provides more sport for the fisherman.

The spotted bass, M. punctulatus, is found between Ohio and Florida and in parts of Kansas and Texas. The spotted bass may reach up to 4 lb (1.8 kg). This fish is found in cool, fast flowing waters like the smallmouth bass, but may also be found in deep water (100 ft, 33 m). Three other species resemble the spotted bass. These are the Guadalupe bass, M. treculi, reaching a weight of 1 lb (0.45 kg), the Suwanee bass, M. notius, of northern Florida weighing under a pound, and the redeye bass, M. coosae, of the Alabama River and nearby areas, weighing up to 2 lb (0.9 kg).

The saltwater basses are distinct from the freshwater basses, and most are included in the family Serranidae. Although designated as saltwater fishes, some of these bass may be found in fresh or brackish water. Some of these species are prized sport fishes especially for the hook and line enthusiast. Saltwater bass have the characteristic basslike or perchlike body shape with a thick spine on the first dorsal fin and a soft rayed second dorsal fin. Saltwater bass vary in size from massive forms of about 1,000 lb (454 kg) to tiny individuals under 1 in (2.5 cm) long, some of which are aquarium fish.

The belted sandfish, Serranus subligarius, matures when it reaches 2 in (5 cm) in length, and grows to a maximum of about 6 in (15 cm) long. The belted sandfish is found in the tropical Atlantic and Caribbean and may descend to deeper waters of 60 ft (20 m).

Sea basses in the genus Morone are occasionally found in fresh water. Some taxonomists group these fish with the wreckfish (Polyprion americanus) and the giant sea bass in the family Percichthyidae rather than the Serranidae. The wreckfish reaches lengths of over 6 ft (2 m), weighs up to 100 lb (45 kg), and descends to depths of 300 ft (1,000 m).

The striped bass, Morone saxatilis, also called rockfish, rock bass, or striper, inhabits the waters along the mid-Atlantic coasts from the St. Lawrence River to northern Florida. Some specimens of striped bass transferred to the Pacific Ocean off California in 1879 have established themselves well and are now abundant. The striped bass may reach 100 lb (45.4 kg), although most average approximately 10 lb (4.54 kg) and are highly prized for sport and food. Striped bass spawn in fresh waters in early summer; some have become landlocked in the Santee-Cooper Reservoir in South Carolina.

Groupers (genus Epinephelus) frequently gather on rocky shores. Groupers are popular sport fish, caught by Two striped bass on the ocean floor. Photograph by Andrew J. Martinez. The National Audubon Society Collection/Photo Researchers, Inc. Reproduced by permission. rod and reel as well as by hand line, and highly prized for their superb flavor. Examples are the red grouper, E. mario, the Nassau grouper, E. striatus, the red hind, E. guttatus, and the rock hind, E. adscensionis.

In Australia the Queensland grouper, E. lanceolatus, reaches half a ton in weight and has a huge appetite. There are reports that this giant fish stalks pearl and shell divers, and there are unconfirmed tales of divers being swallowed by groupers.

A close relative of the Queensland grouper is the giant jewfish (Epinephelus itajara), which frequents the Caribbean up to Florida and also the Pacific Ocean in the Gulf of California, Mexico, and Panama. Although the jewfish's weight averages about 20 lb (9 kg), some may weigh up to 100 lb (45.4 kg) or more. A rod and reel catch of a 680 lb (309 kg) specimen has been reported. To catch the larger fish, shark hooks and ropes may be used. The large fish are cut into steaks and fillets.

The taste of the smaller fish is preferable to that of the larger specimens, which are edible but have a strong flavor.

Several species of sea bass in the Serranidae are hermaphrodites, where both male and female organs are found in the same individual. Cross-fertilization is the rule since fish do not fertilize their own eggs. Examples of hermaphroditic species include Paralabrax clathratus, P. hepatus, and Diplodus vulgaris of the Mediterranean Sea. Most species of true hermaphrodite fish among the teleosts are in the Serranidae, the sea bass family.

Many species of grouper and other sea basses are fish that function as females at first, then transform into males and function as males for the rest of their lives. This explains why large specimens are all males. An example is the Atlantic or black sea bass (Centropristis striatus), which demonstrates this condition. It is found from Massachusetts to North Carolina with some individuals straying to Florida.

The black sea bass demonstrates a distinct form of hermaphroditism characteristic of hermaphroditic groupers, where the sexes are physically distinct. Functional males and females are easily distinguished; the female has a more pointed snout, and is a darker or duller blue color. In July, the post breeding period, some females may be brown or almost completely white. Males at spawning time in May and June may be bright blue, especially around the eyes, with an adipose (fatty) hump behind the head which is most prominent at spawning time. Early in life there is a sex change from female to male, the changeover reaching its summit at about five years of age. By the eighth year there are no females in the population, and the males continue to grow for several more years. As with the groupers this accounts for the fact that the large black sea bass are all males.



Whiteman, Kate. World Encyclopedia of Fish & Shellfish. New York: Lorenz Books, 2000.


Cousteau, J. "The Act of Life." In The Ocean World of Jacques Cousteau Vol. 2. Canada: Prentice-Hall of Canada, 1975.

Hildebrand, S. F., and W. C. Schroeder. "Fishes of Chesapeake Bay." Bulletin of the United States Bureau of Fisheries Vol XLIII, Part I, 1927.

Nathan Lavenda

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