Abbreviated Life History of China Rockfish
(Sebastes nebulosus)

China Rockfish; Photo by Steve Lonhart of Simon/NOAA

The China rockfish is an attractive rockfish, almost entirely black except for a yellow, or yellow-white stripe that runs from the anterior portion of the dorsal fin, along the lateral line, to the tail. It also has yellowish-white speckles all over its body.

Distribution, Stock Structure and Migration

China rockfish occur from Kachemak Bay, northern Gulf of Alaska to Redondo Beach and San Nicolas Island in southern California, but they are most abundant from southeastern Alaska to Sonoma County, California. They are found at depths up to 420 ft, but are most common between 30 and 300 ft. The juveniles are pelagic but the adults are sedentary, associated with rocky reefs or cobble. Adults are solitary, territorial, and residential, traveling less than a meter from their home range of 33 square feet. They are generally found resting on the bottom or hiding in crevices.

Age and Growth

China rockfish live to at least 79 years. Based on a calculated age-length relationship, a 10-in. TL China rockfish is approximately 6-7 yr old and a 12-in. TL fish is approximately 9-10 yr old. A maximum length of 18 inches has been recorded for this species.

Reproduction, Fecundity and Seasonality

Males and females mature at about the same size and age. Off central and northern California, male China rockfish reach reproductive maturity at a total length of 10.2 inches TL and three years of age, while the females reach maturity at 11.0 inches TL and four years of age. Fifty percent of the population of males and females will reach first maturity at 10.6 inches TL and four years of age, and 11.0 inches TL and at four years of age, respectively. All are mature by 12 inches or six years.

Spawning occurs off central and northern California between January and June, with peak spawning in January. Larvae are released later in Alaska, from April to August, peaking in May. Individual China rockfish spawn once a year. Larvae settle out of the plankton between one to two months after release.

Predator/Prey Relationships

Like grass and kelp rockfish larvae, China rockfish larvae are planktivores. Juveniles eat crustaceans, while the adults eat crustaceans as well as ophiuroids, mollusks, and small fishes. Juveniles are prey of birds, porpoises, and fishes, including rockfishes, lingcod, cabezon, and salmon. Predators of adult China rockfish include sharks, dolphins, seals, lingcod, and possibly river otters.

Competition

China rockfish are likely to compete with other demersal species like kelp greenling, cabezon, lingcod, and other rockfishes such as grass, quillback, copper, and vermilion, all of which also inhabit rocky areas.

Critical Habitat

Larvae and early juveniles are pelagic but larger juveniles and adults settle on rocky reefs or cobble substrate, most commonly in depths between 30 and 300 feet. Once they settle, individuals may stay on the same reef for years.

Fishery and Status of Stocks

Their bright colors have made China rockfish a very popular commercial species for many years. They are a high commodity for the live fish fishery, where they are taken by hook-and-line, longline, and trap. No formal stock assessment has been completed for this species. China rockfish is currently managed as part of the Nearshore Rockfish group.

Information on this page was originally presented in the Nearshore Fishery Management Plan (these profiles updated July, 2010).

China Rockfish