Kelp Greenling

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Kelp Greenling

Hexagrammos decagrammus
Other Common Names
Sea trout, kelp trout, greenling seatrout
Other Common Names
Sea trout, kelp trout, greenling seatrout

At the Aquarium

Rocky Coast

Appearance

Kelp greenlings are elongated fish with yellow eyes and 2 cirri above each eye. Males and females differ in color and pattern. Males are a brown-orange with bright blue spots, but during courting this color can change to a uniform gray with blue spots. Females tend to be gray or brown with brown or yellow spots and large dark-brown blotches.

Habitat

Found intertidally and subtidally to 426 feet in shallow coastal waters and inland seas, especially over rocky reefs, kelp beds, and eelgrass habitats.

Diet

As opportunistic predators they eat shrimps, crabs, worms, octopuses, brittle stars, snails, hermit crabs, and small fish.

Life History

Females can spawn up to 3 batches of eggs between July and January. A cluster can have anywhere between 1,580-9,660 eggs. Across the season, a female lays between 28,500-125,000 sticky eggs. Eggs are placed in algae beds, on or between rocks or hard materials made by other animals, such as empty barnacle tests, scallop shells, or worm tubes. The male guards the eggs, which take about 20 days to incubate. Larvae are 0.3 inches at birth and are pelagic, moving offshore into open waters, where they can spend up to a year before returning nearshore, where they settle near rocky reefs and macroalgae but may be found in tidepools.

Kelp greenling can grow to 25 inches long and live to 25 years.

IUCN Status

Least Concern

Ecosystem & Cultural Importance

Native American tribes harvested kelp greenlings for eating. Their remains are common in Native American middens.

The larvae serve as food to salmon and steelhead. Adults are eaten by other greenlings, lingcod, black rockfish, cabezons, skates, spiny dogfish, pinnipeds and seabirds, including guillemots, murres, and puffins.
Alaska to Southern California
In Oregon, kelp greenlings are caught in both the commercial fishery and the recreational fishery.
A male will guard a nest with as many as 11 separate egg clutches from different females, and they can be in different stages of development. These eggs are preyed on by other kelp greenling and even the male guarding the egg mass. Non-territorial males will also act as sneak spawners, spreading his sperm on the eggs when the male guarding them is distracted.

Though usually solitary, they will sometimes form small groups. During the nesting season males are very territorial.

Citations & Other Resources