Invertebrate · GBIF taxon 2278852
Pacific Purple Sea Urchin
Strongylocentrotus purpuratusAlso known as Purple Sea Urchin, Pacific Purple Urchin
Pacific purple sea urchins use five sharp teeth set in a structure called Aristotle's lantern to scrape algae and excavate small burrows in solid granite coastal rocks. Dense congregations graze kelp holdfasts, occasionally turning vibrant kelp forests into barren rockscapes when top predators are absent. Bright purple spines protect their rounded shells from waves and hungry predators while tube feet anchor them against heavy surf.
MarineInvertebrateKelp Forest
—observations
—countries
—peak records
Not EvaluatedConservation statusIUCN Red List categoriesLCNTVUENCREWEXNot Evaluated — not placed on the risk ladderRed List categories, explained →
Diet & prey
- Giant Kelp
- Bull Kelp
- Coralline Algae
Predators
- Sea Otter
- Sunflower Sea Star
- California Sheephead
ThreatsOcean warming, marine heatwaves, and loss of keystone predators
HabitatsRocky intertidal zones, subtidal reefs, and kelp forests
Life spanup to 50 years
Size / weightNot available
Classification
- FamilyStrongylocentrotidae
- SpeciesStrongylocentrotus purpuratus
Range data is not available yet.
Interaction riskLow
- Low
- Moderate
- High
- Very high
- Why interaction risk is low
- Safe to observe at a normal distance; watch your step to avoid sharp spines in tidepools.
Responsible observation
- Tidepool Etiquette: Observe urchins in place without prying them off rocks to avoid damaging their delicate tube feet.
- Footwear Safety: Wear hard-soled water shoes when exploring rocky intertidal shores to protect feet from sharp spines.
Predator Jerry Kirkhart from Los Osos, Calif. / CC BY 2.0 · cc-by
Predator (c) Cricket Raspet, some rights reserved (CC BY), uploaded by Cricket Raspet · cc-by
Primary Food Source "Giant kelp (Macrocystis pyrifera), Monterey Bay aquarium, California" by LT&C is licensed under CC BY 2.0. To view a copy of this license, visit https://creativecommons.org/licenses/by/2.0/. · cc-by
Close Relative no rights reserved, uploaded by Braden J. Judson · cc0
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