A national marine sanctuary can be in coastal and ocean waters and in the Great Lakes. There are currently 14 national marine sanctuaries in the United States. The water at Gray's Reef is 50 to 70 feet deep. Gray's Reef is 22 square miles. Gray's Reef is home to many types of animals.
Fish are a part of the group of animals known as vertebrates, or animals with backbones.
Some examples of these fish are black sea bass, snapper, grouper, mackerel, gobies, Queen angelfish, barracuda, nurse sharks, and moray eels. Some of these fish only live there part of the year depending on the temperature of the water. These fish all feed in different parts of the reef. For example some small fish feed in small hiding places in the reef while other larger fish feed in the waters above the reef. Gray's Reef is also home to many types of animals which don't have backbones, called invertebrates .