Kelp Greenling

Quick Take

• Male kelp greenlings pull off a mating strategy so unusual it barely seems like fair play, and the whole thing starts with someone else's nest. See the mating strategy →
• Most fish have one lateral line, but kelp greenlings break that rule in a way their own scientific name tries to explain. Explore the scientific name →
• Male and female kelp greenlings look so different, you'd be forgiven for thinking they're two separate species. Compare male and female looks →
• Kelp greenlings are prized as some of the tastiest fish around, yet there is one step in the kitchen that trips up nearly every angler who catches them. Find the deboning challenge →

The kelp greenling is a species of fish that inhabits kelp beds and sand bottoms in the rocky nearshore regions of the northern Pacific. It consumes small fish, mollusks, crustaceans, polychaete worms, and brittle stars. Large predators like lingcod and halibut eat the young. Divers and fishers frequently catch them by spear, hook, and line from shore or a boat.

Kelp Greenling Fun Facts

• The scientific name of the kelp greenling comes from the Greek terms hex, meaning “six,” deca, meaning “ten,” and gramma, meaning “line.”
• This fish species is one of the few fish with five lateral lines on each side.
• The kelp greenling inhabits rocky bottoms and kelp beds at depths of up to 150 feet.
• Male kelp greenlings participate in an unusual mating ritual by fertilizing eggs in the nests of other males.
• Aleut Indians called these fish idyajuk; the Indian tribes place a high value on them.

Classification and Scientific Name

The kelp greenling, known as Hexagrammos decagrammus, belongs to the family Hexagrammidae and is part of the class Actinopterygii, also known as ray-finned fish. Greenlings are generally distinguished by traits including thin scales, long dorsal fins, and strong jaw teeth.

Appearance

Small red-brown to golden patches cover the female kelp greenling’s body, standing out against a grey or brown background. Most of the fins are orange-yellow. The anterior half to two-thirds of a male kelp greenling’s body can be covered with irregular blue spots on a grey to brown-olive background.

Inside their lips, both sexes have a yellowish hue. In addition, they display two pairs of cirri, one pair over each eye and the other pair on top of their heads, as well as five lateral stripes on each side of their bodies, which can be used to identify them. Both males and females can weigh 2 to 5 pounds and have a body length of 15 to 24 inches.

Distribution and Habitat

Kelp greenlings are commonly found in parts of central and northern California. In addition, they are abundant in the ocean from La Jolla to Attu Island in Alaska.

Sandy bottoms, shallow seas, and coastal locations make up the preferred habitat of this type of fish. However, they prefer cold, deep waters, particularly in southern California, where these fish are typically located in 150-foot-deep kelp beds.

Predators and Prey

Kelp greenlings eat crustaceans, brittle stars, mollusks, and whatever little fish they can find in the bottom depths of the ocean. Huge predators of marine mammals like lingcod and halibut find kelp greenlings very appetizing. This fish is also preyed upon by seabirds that dive into the water from the surface.

Reproduction and Lifespan

Approximately one-third of male greenlings are sexually mature at age two, with about half reaching maturity by ages three to four. Females spawn in fall and winter. During each spawning season, females can lay at least three clutches of blue eggs.

The male greenling protects the egg masses from predators and frequently fans the eggs. The male ensures that the eggs get enough oxygen after the female greenlings have laid their eggs. Notably, males select the nesting location and attract several females to spawn their eggs there so the male can fertilize them.

Fishing and Cooking

Anglers are recommended to catch kelp greenlings from shore using a hook and line. When the tide is coming in, it is advisable to cast a line near areas where waves break, such as the base of kelp forests, pilings, seawalls, or rocky shorelines. Anglers can use an abrasion-resistant fusion line with a medium spinning tackle to catch these fish.

Bait options include clams, shrimp, mussels, worms, squid, and small bits of fish. Additionally, fishermen might use feathered jigs with squid as the tip. Kelp greenlings are challenging to land because they fight hard, resisting anglers’ lines and tangling them in kelp. The south jetty in Eureka, in northern California, is the best place to catch kelp greenlings, making them one of the most popular catches for an average fisherman.

The kelp greenling is considered one of the tastiest fish of its kind, suitable for a variety of cooked dishes. Their meat is flaky and delicate, slightly resembling the flavor of trout. The only drawback to preparing this fish is the tedious deboning process, which is necessary because the bones are small and sharp and may be harmful if swallowed.