Purple Sea Urchin

Individuals in the intertidal decorate themselves with shells, rocks and pieces of algae as protection from sun and predators.

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Taxonomic description

• Key identifying features for this sea urchin are purple spines that protrude from a round body. ^[3]
• Ranges in size from 5-10 cm (2-4 in) wide by 4 cm (1.6 in) tall. ^[3]
• Adolescents have mostly pale green spines that darken to purple as they mature. ^[3]

Distribution

• Found along the Eastern Pacific from Baja California, Mexico up the coast to Alaska. ^[3]

Life history

• Average lifespan of 20 years. ^[4]
• Is a seasonal breeder; January, February, and March are primary reproductive months. ^[4]
• Oviparous reproducer, where the development of the offspring occurs outside the mothers body. ^[4]
• Fertilized eggs settle on a substrate where it begins to develop. ^[3]

Habitat

• Rocky intertidal and kelp beds, founds in depths of up to 160 meters (525 ft). ^[4]
• Water temperatures in excess of 22.8°C (73° F) increase mortality. ^[3]
• Primarily eats algae including giant kelp; predators include starfish, otters, and humans. ^[4]
• One of the primary natural predators of urchin, the sea otter, is endangered which has allowed for a population boom and subsequent reduction in kelp in some areas. ^[3]

Harvested as food in the 1990s, this species is now mostly harvested for scientific research.

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Seasonal availability

• Available year round. ^[3]

Regulatory and managing authority

• As established by the Marine Life Management Act, the California Fish and Game Commission regulates the fishery, and the California Department of Fish and Wildlife manages this fishery in state waters. ^[12]
• The California Sea Urchin Commission and the Pacific Urchin Harvesters Association combines input from the industry and government entities to inform regulatory and management measures for this fishery. ^[6,9]

Gear type

• Hand picked using SCUBA, and an urchin rake to collect urchin in mesh bags. ^[1,2]

Status of the fishery

• The California fishery was launched in the early 1990’s with export to Japan and the Mediterranean, where it is considered a delicacy ^[3,5], but shipping costs, and limited harvest areas and season (Sept-Oct) for high quality urchin made it not viable. ^[2,10]
• There are currently no major conservation efforts, with populations in some areas, such as Northern California, large enough to be suppressing kelp. ^[4,10]
• Fishery is small and predominantly in Southern California aimed at scientific research demand ^[2,3], although efforts to renew the fishery in northern California are being considered to relieve grazing pressure on kelp. ^[10]

Potential ecosystem impacts

• Harvesting has minimal environmental impacts due to hand harvesting methods.
• Local harvest may limit urchin population booms form sea urchin barrens. ^[8,10]

It is easy to spot sea otters that regularly eat purple sea urchin because their teeth turn purple!

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Edible portions

•  Gonads from females and males (that produce roe or milt). ^[6]

Description of meat

• Color of the roe ranges from yellow to orange. ^[7]
• Soft and buttery with a sweet and salty deep ocean flavor. ^[7]

Culinary uses

• It can be eaten fresh or live from the shell. ^[6] 

• Prepared raw, baked, sautéed, or steamed. ^[6]

• Commonly used in dishes such as sushi and pasta, but can be found in a variety of dishes and cuisines. ^[6]

• For a tutorial on how to open a sea urchin at home, visit Youtube. ^[13]

Nutritional Information 

• A 100 g (3.5 oz ) raw serving of roe is a good source of fatty acids, proteins, minerals, and vitamins. ^[6,11]

Toxicity report

• No known toxins. ^[4]

Seasonal availability

• Available year round in California. ^[4]