Coral reefs serve as vital habitats for a diverse range of marine life, supporting biodiversity and food webs in coastal ecosystems.

The primary function of coral reefs in U.S. coastal ecosystems is to provide habitat and shelter for countless marine species, including fish, crustaceans, and mollusks. Coral reefs are some of the most biodiverse ecosystems on Earth, supporting an abundance of life. Their primary function is to provide a home for marine life, but they also aid in preventing erosion of beaches by lowering wave energy and may assist produce oxygen through photosynthesis by symbiotic algae. By stabilizing sediments, they can indirectly improve the quality of water, but they do not directly filter contaminants.