The littoral zone is the region of ocean extending 600 feet out from the shore. Three sub-zones comprise the littoral zone: the supralittoral, eulittoral and sublittoral zones. The sublittoral zone extends to a depth of about 650 feet and is continuously below water. Coral and anemones are more plentiful in the sublittoral zone than in other regions of the intertidal zone because the zone is comparatively more stable in temperature and the amount of sunlight it receives. Sea stars and sea urchins also take advantage of the warm, sunlit waters of the sublittoral zone.
On North America's west coast, the dungeness crab is an economically important intertidal resident. These crabs reside in beds of eelgrass on the sublittoral ocean floor, scavenging ocean carrion and preying upon small fish and other crustaceans. While the dungeness crab is an important food crustacean on the west coast, concerns have arisen about its introduction in the Atlantic and its possible effects on native fauna.
Algae and plantlife are also plentiful in sunny sublittoral waters. This provides an excellent food source for much of the intertidal fauna. However, excessive algae and plant material can block sun from the ocean floor and cause overcrowding for other species.Learn more about Marine Life