
Coral reef - Wikipedia
A coral reef is an underwater ecosystem characterized by reef-building corals. Reefs are formed of colonies of coral polyps held together by calcium carbonate. [1] Most coral reefs are built from stony corals, whose polyps cluster in groups. Coral belongs to the class Anthozoa in the animal phylum Cnidaria, which includes sea anemones and ...
Coral reef ecosystems - National Oceanic and Atmospheric Administration
Feb 25, 2025 · Coral reefs are some of the most diverse ecosystems in the world. Coral polyps, the animals primarily responsible for building reefs, can take many forms: large reef building colonies, graceful flowing fans, and even small, solitary organisms.
What is a Coral Reef? - NASA
Oct 15, 2024 · Coral reefs cover only 1% of the ocean floor, but support an estimated 25% of all marine life in the ocean, earning them the moniker ‘rainforest of the sea.’ They also play a critical role for coastal communities; preventing coastal erosion, protecting coastlines from hurricane damage, and generating $36 billion in annual income worldwide.
Coral Reefs - NOAA's National Ocean Service
Hidden beneath the ocean waters, coral reefs teem with life. Coral reefs support more species than any other marine environment and rival rainforests in their biodiversity. Countless numbers of creatures rely on coral reefs for their survival.
Corals and Coral Reefs - Smithsonian Ocean
Coral reefs are the most diverse of all marine ecosystems. They teem with life, with perhaps one-quarter of all ocean species depending on reefs for food and shelter. This is a remarkable statistic when you consider that reefs cover just a tiny fraction (less than one percent) of the earth’s surface and less than two percent of the ocean bottom.
Coral reef | Description, Geochemistry, Origins, & Threats
Feb 28, 2025 · Coral reef, ridge or hummock formed in shallow ocean areas by algae and the calcareous skeletons of coral polyps and other coelenterates. A coral reef may grow into a permanent coral island. Often called ‘rainforests of the sea,’ coral reefs are home to a spectacular variety of organisms.
Coral Reefs - Education
Nov 21, 2024 · Coral reefs are important ocean habitats and offer a compelling case of the risks of climate change. Reefs provide a large fraction of Earth’s biodiversity —they have been called “the rainforests of the seas.”
Coral Reefs - Oceans, Coasts & Seashores (U.S. National Park Service)
Coral Reefs are amazing habitats; offering vibrant colors and the greatest biodiversity of any marine ecosystem on the planet. Some coral reefs are so large they are even visible from outer space! But coral reefs only occupy less than one tenth of one percent of the ocean floor.
Basic Information about Coral Reefs - US EPA
Feb 5, 2025 · Coral reefs provide habitat for a large variety of marine life, including various sponges, oysters, clams, crabs, sea stars, sea urchins, and many species of fish. Coral reefs are also linked ecologically to nearby seagrass, mangrove, and mudflat communities.
Coral Reef - Oceana
Often nicknamed the “rainforests of the sea,” coral reefs are some of the most diverse ecosystems on Earth. Scientists believe that more than a million species around the world live on coral reefs. At any one reef, thousands of species can be collected or observed living there.