Purple Olive Snail (Olivella biplicata)

Description: The purple olive snail is a striking mollusk found in the intertidal and subtidal zones of coastlines. They get their name from their resemblance to olive pits and their gray shells that have a purple tint to them. Aside from those characteristics, purple olive snails also have a slight striping pattern that runs across their shell from the base to the pointed tip. Shells of purple olive snails are usually 3.5 centimeters long.

Habitat: Aside from being found at Haystack Rock, these snails are found along the Pacific Coast of North America from southern Alaska to Baja California, Mexico.

Diet: Purple olive snails are predators that mostly eat bivalves (mollusks like clams, mussels, scallops, etc.) and carrion (AKA dead animals), but they’ll also eat kelp blades or detritus in the water. A common predator of purple olive snails is the moonsnail. 

Tide Pool Tidbits:

• If you see a thin trail in the sand at the beach, it’s probably from a purple olive snail! A bump in the sand at the end of a trail like this indicates the location of a snail that has burrowed underground.

• When they’re moving, purple olive snails position their foot in front of their shell to use as a plow while they burrow in sand.

• Purple olive snails are active at night and burrow underground when the tide is low. 

• Purple olive snail shells are used in traditional jewelry and clothing of coastal Indigenous populations.

• While hiding, purple olive snails cover the opening of their shell with a structure called an operculum which acts as a barrier. Hermit crabs will also take over abandoned purple olive snail shells and live in them. If you ever find a purple olive snail shell and would like to keep it, make sure you’re in an area where collecting is allowed and that no creature is living inside!

Reference: Central Coast Biodiversity