Details
Strongylocentrotus droebachiensis
A green urchin of cold northern seas. Its round test is covered with short spines, and it grazes algae on rocky coasts and kelp beds.
Map: Ecoregions 2017 © RESOLVE (CC BY 4.0) · Natural Earth (PD)
Occurs in northern Atlantic, Pacific, and Arctic waters, especially on rocky bottoms, gravel, and the edges of kelp forests.
Adults are often about 5 cm across, with large individuals exceeding 8 cm. The color ranges from green to purplish green.
It moves slowly with tube feet and spines, often gathering under algae or in rock crevices. Dense populations can strongly graze kelp beds.
It mainly eats seaweeds such as kelp, but also uses attached organisms and organic material. Its jaw apparatus scrapes surfaces.
Males and females release sperm and eggs into the water, mainly in spring. Larvae drift before settling and transforming on the seabed.
The gonads are harvested as seafood. Because grazing can reshape kelp forests, the species matters in coastal ecosystem management.
