Purple Encrusting Sponge (Haliclona cinerea)
Purple encrusting sponge (photo credit: Molly Sultany)
Description: The pores of purple encrusting sponge can sometimes take on a volcano-like appearance; other times, they simply look like holes on a flat surface. They are most often a purple color but may also appear gray.
Habitat: Purple encrusting sponge is commonly found in the mid intertidal zone down to depths of 50 m. They range from Alaska to southern California. We often find the sponge on rocks in The Needles or on the north side of Haystack Rock, often on the underside of rocks or in shady areas.
Diet: They filter feed in the water in order to eat things like detritus, plankton, and they can even filter dissolved nutrients in the water into their bodies.
Tide Pool Tidbits:
Spotted leopard nudibranchs eat purple encrusting sponge and are commonly found nearby.
As colonial encrusting animals, the purple encrusting sponge can be anywhere from a centimeter to a meter across and cover any hard surface as they grow. This means sometimes they are even seen growing on mussels!
Reference: The New Beachcomber’s Guide to the Pacific Northwest by J Duane Sept