Clathria prolifera (Ellis & Solander, 1786)
This colorful, branching sponge, commonly referred to as the Red Beard Sponge, is very conspicous in dock fouling from the Central Bay, South Bay and southern San Pablo Bay. Clathria prolifera is native to the Atlantic Ocean and was first found in San Francisco Bay in the mid- to late 1940's. It is believed to have arrived here with Atlantic oyster shipments or as fouling colonies on ship's hulls. (Adapted from Cohen and Carlton, 1995)