We found this Pisaster scavenging on the remains of a bony fish near a wharf. A dead fish obviously had been thrown from the wharf and thus became available to a seastar that could not have caught the living animal. Depth 16 m.
With tube feet attached, Pisaster slowly moves its captured prey along one arm toward the mouth. The seastar then turns the snail so it can insert its stomach through the shell's aperture and digest the snail. The shell, with a barnacle attached, later will be discarded. The encounter was set up in our home aquarium.
This aboral view (in other words, view from the top) of the ray shows the line of large carinal spines down the aboral surface and the ragged rows of spines on each side. Notice the cushions of small pedicellariae which surround each spine. Also notice the large individual pincer-like pedicellariae and the abundant papulae between the spines. Photo by Dave Cowles, July 2008
This lateral view of the rays shows the scattered rows of spines, the abundant large pedicellariae and papulae among the spines, and the rows of adambulacral spines along the bottom.
Orthasterias koehleri from 70 m depth, San Juan Channel. This individual recently lost two of its rays. Ray length is 20 cm. (Photo by: Dave Cowles, July 2008)
Pisaster ochraceus (Brandt, 1835) Common Names: Ochre sea star, Purple sea star Individual found at Swirl Rocks, WA in the mid-intertidal zone. Top view, approximately 40 cm in diameter. Photo by: Melissa McFadden, June 2002.