Burrowing Sea Anemone
Scientific Name: Anthopleura artemisia
Category: other
Brief Description
A marine invertebrate that lives partially buried in sandy or silty substrates, often covered in shell fragments or debris for camouflage.
Characteristics
Features numerous thin, slender tentacles that extend from a buried central column. The column is often covered in sticky verrucae (bumps) that hold bits of sand, gravel, and shell. Tentacles can vary in color from dark brown and black to green or patterned.
Habitat
Intertidal zones, specifically sandy or muddy beaches and tide pools where they can anchor to buried rocks.
When to Find It
Visible during low tides year-round.
Conservation Status
N/A
Ecological Role
Acts as both a predator of small invertebrates and a host for symbiotic algae (zooxanthellae), contributing to the local marine food web.
Easily Confused With
Moonglow Anemones (Anthopleura elegantissima) are similar but typically live in dense colonies on exposed rocks rather than buried in sand.
Observation Tips
Look for a ring of slender tentacles appearing to grow directly out of the sand during low tide at beaches like Alki. Avoid stepping on them as they are soft-bodied.
Interesting Facts
Unlike many other anemones that sit on top of rocks, this species can retract entirely beneath the sand surface if disturbed or when the tide goes out to prevent drying out and predation.
User Notes
Alki Beach WA