Bread Crumb Sponge
Bread Crumb Sponges have a flat base with several randomly-arranged projections each having an osculum (large pore) on top. This Bread Crumb Sponge was found in a tide pool at Acadia National Park (a tide-poolers dream). Algae impart the greenish color shown; this represents a mutualistic relationship in which the algae provide food via photosynthesis in exchange for shelter. Bread Crumb Sponges are typically an understated grayish-green without the presence of such algae. The name of this species is derived from the way it breaks in your hand when handled; this is said to resemble how bread crumbles. This species also has a strong odor due to presence of sulfur compounds1,2. They can be found from low tide line to approximately 200 feet deep2.
Range: Arctic – Cape Cod; Alaska – Southern California2
Size: covers an area up to 2ft1, 1 cm (0.5 in) thick; other source says 30 cm (1 ft) by 5cm (2 in) high2
Similar Species: Bowerbank’s Crumb of Bread Sponge (H. bowerbanki) has the same range, but the spicules differ slightly2
1. Watling, L., Fegley, J., Moring, J., White, S., Sulzer, A. (2003) Life Between the Tides. Tilbury House Pub
2. The Audubon Society Field Guide to North American Seashore Creatures