A Caribbean barrel sponge is essentially a host to a colony of animals. Made of several cell layers, barrel sponges construct a wall of spicules in the shape of a large tube or bowl. The sponge's cells then pump water through its permeable wall, allowing the sponge to capture microscopic plankton for food. Because of this process, other invertebrate filter feeders and reef fish are attracted to the siphon-induced current of water initiated by the sponge. This Netted Barrel Sponge (Verongula gigantea), photographed at a depth of 8 m in the Cayman Islands, is surrounded by a community of polychaete feather duster worms (Anamobaea orstedii), bryozoans (Schizoporella sp.), tunicates (Eudistoma sp.), hydroids (Gymnangium sp.), zoanthids (Palythoa caribaeorum), and various other sponges.
The reefs in the Cayman Islands are managed under strict marine conservation laws establishing a zoned system of Marine Protected...
