The black sea bass is a bottom-dwelling fish, often mistaken for the similar-looking striped bass. This fish is immediately distinguishable from the striped bass becuase it is much darker in color, and the soft and spiny parts of the dorsal fin are continuous, rather than separated in two parts, and marked with white spots and bands. Its caudal and pectoralfins have round edges.

Stout-bodied, the black sea bass has a moderately pointed stout and a large mouth. Its head is flat and smooth, with large eyes set high on the head. The pale centers of the scales form light, narrow stripes along the sides of the fish. The male fish tends to develop a fatty hump on its back in front of the dorsal fin and is usually more darkly colored than the female.

The black sea bass is the only cold-water member of the large sea-bass family, a family that includes groupers. It can be distinguished from temperate basses by the three spines on the gill cover and by the continuous dorsal fin.

The majority of black sea bass undergo a sex reversal between the ages of two and five. All black sea bass start out as females, then they transform into males. Finding females older than eight years old is rare, but males can live up to 15 years.

The black sea bass is an omnivorous bottom feeder and usually eats mollusks, crustaceans, small fish, and bottom plants. Unlike the striped bass, black sea bass are confined strictly to saltwater environments and do not migrate to spawn in fresh water.

Although black sea bass are solitary and usually territorial, they gather in large groups in deep water to spawn in late spring.

The black sea bass is an important bottom-fish species of the mid-Atlantic, taken for both food and sport. The numbers taken recreationally in New England waters are generally greather than the numbers taken commercially.

Although the number of landings has not decreased dramatically in the last 15 years, there is rising concern about the health of the stocks, as the average size of individual fish has become smaller.