Lingcod

What it is

The lingcod is a member of the greenling family, despite its misleading name suggesting a relation to cod or ling. It features a fusiform body designed for quick bursts of speed, with a large head and mouth containing eighteen sharp, canine-like teeth. The skin is covered in cycloid scales, while the head remains unscaled with a small cirrus above the eye. Colours vary from gray and brown to green, often with copper mottling on the back. A prominent white lateral line runs along the side. Notably, about twenty percent of the population exhibits blue-green flesh due to biliverdin pigment, which disappears upon cooking.

Where it lives

This species inhabits the North American Pacific coast, extending from the Shumagin Islands in the Gulf of Alaska down to Baja California in Mexico. They are most abundant off British Columbia and Washington. Lingcod dwell near the ocean bottom, preferring rocky areas at depths between ten and one hundred metres, though they have been recorded as deep as 475 metres. Tagging studies indicate they are largely non-migratory, staying within localized areas. Larvae live near the surface, while juveniles occupy sandy bottoms with eelgrass before moving to deeper rocky reefs as adults.

How it lives

Adult lingcod are aggressive predators that consume almost any prey they can swallow, including rockfish, squid, octopus, crab, and other lingcod. Juveniles feed on small fish, while larvae eat zooplankton and krill. They lack a swim bladder, relying on their body shape for movement. While generally sedentary, females migrate seasonally to spawn in shallower waters. Males remain in their natal habitats, displaying territorial behaviour. This site fidelity helps them return to specific reefs. Predators include seals, sea lions, and humans, particularly when the fish are vulnerable during spawning migrations.

Breeding and life cycle

Spawning occurs annually between January and March, likely at night. Males establish territories in nearshore grounds starting in November, showing high fidelity to specific nesting sites. Females lay up to 500,000 eggs under rocks or in crevices within a male's territory and then depart. The male fertilizes the eggs and guards the nest actively for six weeks until hatching. He may defend up to three nests if they are close together. Larvae are pelagic until late spring, when they settle to the bottom. Females mature at three years, while males mature at two years.

Fish and people

Lingcod is a popular food fish, prized by anglers for its size and fighting ability. It is managed by NOAA Fisheries in the United States and the Alaska Department of Fish and Game. Regulations include minimum size limits to ensure fish spawn before harvest, as well as seasonal closures to protect nesting males and spawning females. Catch limits restrict daily bags for sport fishing. The species is not currently considered overfished. Its unique blue flesh is a notable culinary curiosity, though the colour does not persist after cooking.

Status and threats

Both the Northern and Southern Pacific stocks are assessed as not overfished and not subject to overfishing based on 2021 data. Management strategies focus on preventing overexploitation, as recovery from population declines is difficult for this species. Protective measures include closing fisheries during spawning and nest-guarding periods. Minimum size limits help maintain the breeding population. The International Union for Conservation of Nature status is not explicitly listed in the provided text, but national assessments indicate healthy stock levels under current management regimes.

Relatives and look-alikes

The lingcod is the only living member of the genus Ophiodon. An extinct, slightly larger species, Ophiodon ozymandias, is known from Late Miocene fossils in Southern California. Although called a cod, it belongs to the greenling family Hexagrammidae. It is distinct from true cods and lings. The Cabezon, another fish in the same range, also exhibits blue coloration, suggesting similar environmental or dietary influences on pigment production.

Questions people ask about Lingcod

Good reading and sources

• Lingcod on WikipediaEncyclopedia
• More photos on Wikimedia CommonsPhotos
• Wikidata recordOpen data