Marine Management News Fish Identification Quiz
October 2010

October 2010 Fish Quiz

This species of fish hatches from a clutch of around 4,000 eggs after an incubation period of four to five weeks. The newly hatched young, which measure about one-third of an inch long, may spend up to a year drifting with ocean currents and feeding on tiny crustaceans such as copepods before settling to the bottom near shore.

Both males and females measure around seven inches long by the time they reach three years of age, but thereafter males grow more slowly. Both sexes reach their maximum size by age 12. This species generally reaches a length of around 18 inches, but individuals 24 inches long have been reported.

The two sexes were thought to be different species of fish for over 70 years, until it was discovered that males and females exhibit different coloration (its mostly a matter of spots - and yes, that's a hint!).

Females are sexually mature by four years of age. During the spawning season, which most biologists believe to occur between September and December off California, females lay golf- to tennis-ball sized egg masses at nesting sites chosen by the males. These sites may be established in a variety of locations, from kelp to rocky reefs, and are aggressively guarded by the males. Spawning females produce at least three egg clutches per season, and multiple females may contribute to a single nest.

Adult fish of this species eat a wide variety of food including crabs and other crustaceans, worms, and juvenile fishes. The primary predators of this fish (other than fishermen) are lingcod and harbor seals.

This species is abundant from the Aleutian Islands, Alaska, to central California but is occasionally seen as far south as La Jolla, in southern California. It inhabits kelp beds and rocky reefs but is also known to frequent sandy bottom areas. It is a near shore species found in depths shallower than 150 feet.

This fish is popular with recreational anglers, especially in the northern part of the state. Until the late 1990s, this species was only caught incidentally by commercial fishermen, and landings of sport-caught fish far exceeded any commercial catch. However, in 1997 the emergence of the commercial "live-fish" fishery, where fish are carefully handled when caught and later sold from seawater tanks while still alive, saw commercial landings skyrocket past the recreational catch. The commercial fishery peaked in 2000 when landings reached 52,000 pounds, compared to a high of 5,700 pounds prior to the inception of the live-fish fishery. In 1999 the CDFW reduced the recreational bag limit to 10 fish, followed by further size and bag limit reductions in subsequent years. In the commercial fishery, the CDFW set a catch limit of 19,400 pounds in 2001. The total catch limit was reduced again in 2002, and in 2003 access to the commercial fishery was restricted to a certain number of permit holders. Currently, landings of this species both in the recreational and commercial fisheries are much reduced as a result of regulatory action.

This fish is a female kelp greenling, Hexagrammos decagrammus. It differs from the male in that it has brown spotting/mottling with yellow highlights, whereas the male has bright blue spotting on an olive green/brown background. The current bag limit is two fish within the 10-fish RCG Complex bag limit of all species of rockfish, cabezon and greenlings combined (per CCR Title 14, Section 28.29(b)).