Sponge Reef - Ecological Significance

Ecological Significance

Sponge reefs provide structure on the otherwise relatively featureless continental shelf. They provide habitat for fish and invertebrates, and may serve as an important nursery area for these animals. More research is required to determine the full ecological importance of these reefs.

Observations by manned submersible indicate that the fauna of sponge reefs differs from surrounding areas. Organisms found in and around sponge reefs include annelid worms, bryozoans, spider crab, King crab, shrimp, prawns, and euphausids. Echinoderms, especially sea urchins and sea stars, were abundant in areas of the reef where the sponges were dying or deceased, and can be used as an indicator of sponge reef health. Rockfish, especially Sebastes species, live in openings and in between sponges. Gravid and juvenile rockfish were observed, suggesting that the reefs are being used as a nursery area. Foraminiferans are abundant around the reefs, and diatoms are scarce. The consortium of organisms living in and around sponge reefs has changed very little since the Jurassic.