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A fragile pink urchin resting on sandy seafloor

Fragile pink sea urchin

Strongylocentrotus fragilis

Animal type
Invertebrates
Ecosystem
Deep sea
Relatives
Other sea urchins, sea stars, sand dollars
Diet
Plant and animal scraps, including kelp that drifts down from surface waters
Range
Seafloor at depths of 300 to 1,600 feet (91–488 m)
Size
Up to 4 inches across (10 cm)

Meet the fragile pink sea urchin

An urchin "walks" on tiny tube feet, much like a sea star does. When an urchin finds their favored food like kelp, they use five rasping teeth to scrape at their snack and push tiny pieces into its mouth. This urchin feeds on algae and animal scraps that drift down from shallower waters. 

Did you know?

The fragile pink urchin is an abundant sea urchin off the Monterey coast. They may go for long periods without food, surviving on stores of fat.

An urchin's mouth is on the bottom of its body.

Conservation

Anything that finds its way into the ocean, whether it's tossed away as trash, washes off a beach or falls off a boat, may eventually make its way to the deep sea. The deep sea isn't so far away that it's beyond the reach of human activities. Living creatures in the deep like the fragile pink sea urchin are affected by what we do at the surface.

Want to see amazing deep-sea creatures up close? Visit our exhibition, Into the Deep: Exploring Our Undiscovered Ocean (En lo Profundo: Explorando Nuestro Océano Desconocido).

Want to see amazing deep-sea creatures up close? Visit our exhibition, Into the Deep: Exploring Our Undiscovered Ocean (En lo Profundo: Explorando Nuestro Océano Desconocido).
Learn about the exhibition

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