Kelp Bass

Paralabrax clathratus

Kelp Bass

Paralabrax clathratus

Other Common Names
Rock Sea Bass, Calico Bass

Orford Reef

Other Common Names

Rock Sea Bass, Calico Bass

At the Aquarium

Orford Reef

Appearance

Kelp bass are olive brown in color with yellow spots on their head and two distinctive rows of white blotches on their upper back that looks like a checkerboard. They also have calico spotting on their belly and fins that are yellow-toned.

Juveniles are light brown in color and tend to lack the markings of adult kelp bass.

Kelp bass can grow up to 28.4 inches in total length and weigh up to 14.5 pounds.

During the spawning season, females will often lose their spots and become black while males usually develop yellow-orange snouts and contrasting black and white breeding colors.

Habitat

Nearshore habitats including kelp forests, bays, and estuaries to depths of 61m.

Diet

Juveniles feed on benthic invertebrates and kelp. Adults feed on fishes and cephalopods.

Life History

Mature individuals usually gather to breed in deeper water near kelp beds and rocky headlands. Kelp bass are group spawners and groups can be anywhere from three to over 200 individuals, with several subgroups forming, each consisting of several males and one female.

Kelp bass release their eggs into the water column where fertilization takes place. The eggs drift freely in the plankton of coastal waters. Larvae remain there for 28 to 30 days. They eventually settle into shallow water habitats with algae including kelp.

Kelp bass mature at two to five years old. Females can spawn multiple times within a season. The spawning season occurs from April through November, peaking in the summer months.

The oldest known kelp bass was 34 years old.

IUCN Status

Least Concern

Ecosystem & Cultural Importance

As generalist predators, kelp bass play an important role in both kelp forest and eelgrass habitats.

Kelp bass have been negatively impacted by past commercial and current sport fishing. In the 1970s and 80s, this species was among the top three species taken in sport fisheries. Kelp bass are caught for human consumption and are considered an important game fish. It is also a commercially important species in Mexico. Commercial fishing of kelp bass has been prohibited in California since the 1950s, but they are still caught recreationally in the United States.

The main predator of adult kelp bass is the giant sea bass.

From the Columbia River in Washington to southern Baja California, Mexico. Considered rare north of Point Conception in California.

Kelp bass historically ranged as far north as the Columbia River in Oregon but now it is considered rare north of Point Conception, California.

Adult kelp bass will often school together to prey on small fish. The school surrounds the prey with each kelp bass pursuing from a different direction.

Citations & Other Resources

Iwamoto, T., B. Smith-Vaniz, and R. Robertson. 2010. Paralabrax clathratus. The IUCN Red List of Threatened Species 2010.
California Department of Fish and Wildlife. 2024. Kelp Bass. Marine Species Portal. https://marinespecies.wildlife.ca.gov/kelp-bass/true/
Erisman, B. E., and L.G. Allen. 2006. Reproductive behaviour of a temperate serranid fish, Paralabrax clathratus(Girard), from Santa Catalina Island, California, U.S.A. Journal of Fish Biology, 68(1), 157–184. https://doi.org/10.1111/j.0022-1112.2006.00886.x
Miller, D. J. 1976. Guide to the coastal marine fishes of California / by Daniel J. Miller and Robert N. Lea. Dept. of Fish and Game ; [Division of Agricultural Sciences, University of California], , 1972.
Georgia Aquarium. N.d. Kelp Bass. Animal Guide. https://www.georgiaaquarium.org/animal/kelp-bass/
California Department of Fish and Wildlife. 2024. Kelp Bass Enhanced Status Report. Marine Species Portal. https://marinespecies.wildlife.ca.gov/kelp-bass/the-species/

Kelp Bass

Kelp Bass

Other Common Names

At the Aquarium

Appearance

Habitat

Diet

Life History

IUCN Status

Ecosystem & Cultural Importance

Citations & Other Resources

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