Pisaster ochraceus

Since summer, 2013, sea stars along much of the North American Pacific coast are dying in great numbers from a mysterious wasting syndrome. For more information about this, please click here.

Description
Highly variable in color; most commonly purple, but can also be orange, orange-ochre, yellow, reddish, or shades of brown. A “brilliant purple” morph is common in the inland waters of Washington and British Columbia. Average arm radius in CA/OR is around 9 cm (Harley et al. 2006, Raimondi et al. 2012) but can reach 3x this size. Individuals usually have 5 arms but this can vary from 4 to 7. Aboral surfaces have many small white spines arranged in detached groups or in a reticulate pattern, generally forming a star-shaped design on central part of disk (Morris et al. 1980). Tube feet on the undersides of arms have suckers that allow them to remain attached to rock in high wave energy shores.

Habitat and Geographic Range
Common in the middle to low intertidal zones on wave-swept