Soft corals, which include seas fans, sea feathers and sea whips, don't have the rock-like calcareous skeleton like the others; instead they grow wood-like cores for support and fleshy rinds for protection. Soft corals also live in colonies that often resemble brightly colored plants or trees, and are easy to tell apart from hard corals as their polyps have tentacles that occur in groups of 8, and have a distinctive feathery appearance.

Soft corals are found in oceans from the equator to the north and south poles, generally in caves or ledges. Here, they hang down in order to capture food floating by in the currents that are usually typical of these places.

(Photo courtesy The U.S. Coral Reef Task Force)

What are Coral Reefs?

Coral reefs, and their associated systems of mangroves and seagrasses, are the world's most biologically diverse marine ecosystems. Reef building corals contain tiny cells of symbiotic algae that convert sunlight and nutrients into fuel for coral growth and production. Other types of corals that do not require warm water or sunlight are found in deep water, providing important habitats for commercial, recreational and other species

(Source: U.S. Coral Reef Task Force)	Boulder and massive corals, like this boulder star coral, are the "builders" of the reef. A coral head is a colony of small animals called polyps. These corals provide the reef foundations that are home to millions of reef species. Over 4,000 species of reef fish have been described so far.
(Source: U.S. Coral Reef Task Force)	Elkhorn coral is a branching coral. Branching corals grow in the shallow areas of the reef crest and serve to break up the wave action as it comes onto the reef. The branches of elkhorn coral resemble an elk's rack of antlers, thus its name.
(Source: U.S. Coral Reef Task Force)	Pillar coral forms numerous heavy cylindrical spires that grow upward from an encrusting base. Unlike other hard corals, which feed at night, pillar coral extends its polyps to feed during the day. Fallen pillers may give rise to new upward growing spires.
(Source: U.S. Coral Reef Task Force)	In addition to the hard corals, there are a variety of soft corals like this common sea fan. The calcium carbonate skeleton of soft corals is located within their bodies, allowing them to move with the wave action. Over 800 species of corals have been described to date.
(Source: U.S. Coral Reef Task Force)	Sponges like this orange elephant ear sponge are water filters for the reef. They filter up to 30,000 times their body volume every day. Researchers are discovering unique chemical compounds in sponges and other reef species that may have important medicinal properties and other uses.
(Source: U.S. Coral Reef Task Force)	Corals are large colonies of small animals called polyps. These polyps reside within a cup-like calcium carbonate skeleton. They have a central opening surrounded by tentacles which can be extended to feed on phytoplankton in the water column.

While most of a corals diet is obtained from zooxanthellae, they can also 'fish' for food. During feeding a coral polyp will extend its tentacles out from its body and wave them in the water current where they encounter small fish, plankton or other food particles. The surface of each tentacle has thousands of stinging cells called cnidoblasts, and when small prey floats or swims past, the tentacles fire these stinging cells, stunning or killing the prey before passing it to the mouth.

Why Care about Coral Reefs?

Healthy coral reefs are some of the most biologically diverse and economically valuable ecosystems on earth, providing food, jobs, recreational opportunities, coastal protection and other important services to billions of people world-wide. Unfortunately, many of the world’s coral reefs (including the associated seagrass beds and mangrove habitats) have been damaged or destroyed due to increasing human impacts, climate change, and other factors. According to the Status of Coral Reefs of the World: 2004, 70% of the worlds’ coral reefs are threatened or destroyed, 20% of those are damaged beyond repair, and within the Caribbean alone, many coral reefs have lost 80% of coral species. The decline and loss of coral reef ecosystems has significant social, economic, and ecological impacts on people and communities in the U.S. and around the world.

Benefits
Coral reefs provide habitat for one-third of all marine fish species, build tropical islands, and protect coasts from waves and storms. They contain an array of potential pharmaceuticals, and they support tourism and fishing industries worth billions of dollars. Coral reefs are also fundamental to the fabric of local communities, providing a source of food, materials and traditional activities.

Threats
Critical information is still lacking about the causes of coral decline but evidence suggests a variety of human forces, including population increases, shoreline development, land-based sources of pollution, increased sediments in the water, damage by tourists and divers, groundings, poor water quality from runoff and sewage treatment, and over-fishing, are contributing 

(Source: U.S. Coral Reef Task Force)

The United States is one of many nations around the world working to halt the coral reef crisis and protect, restore and sustainably use coral reef ecosystems. The United States Coral Reef Task Force (CRTF) was established in 1998 by Presidential Executive Order #13089 to lead U.S. efforts to preserve and protect coral reef ecosystems. The CRTF has been instrumental in building partnerships and strategies for on-the-ground action to conserve coral reefs. The Task Force works in cooperation with State, territorial, commonwealth, and local government agencies, nongovernmental organizations, the scientific community, and commercial interests to further the understanding and conservation of our coral reef ecosystems.

The CRTF is responsible for overseeing implementation of the Executive Order, and developing and implementing coordinated efforts to map and monitor U.S. coral reefs; research the causes and solutions to coral reef degradation; reduce and mitigate coral reef degradation from pollution, over fishing and other causes; and implement strategies to promote conservation and sustainable use of coral reefs internationally

Hawaii's Living Reef Ecosystems Facts

• Corals are living animals that eat, grow and reproduce.
• The reef ecosystem feeds, shelters and provides habitats for fish, protects the shoreline from wave and sand erosion and creates Hawaii’s famous white sand beaches and underwater paradise.
• The Hawaiian Islands have 410,000 acres of living reef in the main islands alone, more than the landmass of Oahu.
• A large percentage of coral reefs under U.S. jurisdiction are in the Northwestern Hawaiian Island Coral Reef Ecosystem Reserve (NWHI).
• Hawaii’s living reef ecosystem, sometimes referred to as the “rainforest” of the sea, has more than 7,000 known species of marine plants and animals.
• Hawaii’s coral reef ecosystem, because of its isolation, has more than 1,250 unique species of marine life that can be found only on Hawaii’s reefs.
• Over 25% of all marine life is endemic to Hawaii and scientists are finding new species regularly.
• More than 500 species of marine algae have been identified in Hawaiian coastal waters. Algae produce more oxygen than all the land plants in the world, combined. They are also an important food source for the ocean’s fish and other animals, produce compounds found in gelatin, jam and many other food products. Coralline algae create much of the sand on Hawaii’s beautiful beaches.
• Marine preserves help promote reef life. A good example is Hanauma Bay. Designated in 1967, Hanauma Bay is Hawaii's first marine life conservation district. Because of its protection from fishing pressure, the weight of fish (biomass) in Hanauma Bay is 3-4 times than the estimated abundance for most reef sites on Oahu.
• A Presidential Executive Order in 2000 set aside 84 million acres of ocean around the Northwestern Hawaiian Islands as the Northwestern Hawaiian Island Coral Reef Ecosystem Reserve, the largest conservation area ever established in the United States.
• The majority of the nation’s coral reefs are found around the Northwestern Hawaiian Islands (the 10 mostly uninhabited islets and atolls extending 1,200 miles northwest of the main Hawaiian Islands). Except for Midway and Kure Atolls, these islands, atolls and reefs were set aside by President Theodore Roosevelt in 1909
  in what is now known as the Hawaiian Islands National Wildlife Refuge.

Source: Hawaii’s Living Reef program

Hawaii's Living Reef Importance

Thanks to our living reef, Hawaii has sandy beaches...

Beach sand is primarily made up of worn fragments of coral, shell, urchin, and calcified algae, as well as foraminifera and other minute organisms that float around the ocean.

Thanks to our living reef, Hawaii has big wave surfing...

The shape of the reef is one of the important determinants of how big a wave gets. Without Oahu’s reefs, the world famous surf breaks at Pipeline and Sunset would not exist.

Thanks to our living reef, Hawaii is home to millions of marine creatures – many of them found nowhere else on earth...

The rich algae and coral growth on our reefs provides food and shelter that fish require to survive and grow, from keiki to adult. No reef, no fish.

Over 25% of Hawaiian reef animals are endemic, found nowhere else on the planet. Included in this count are one fourth of all Hawaiian reef fishes, the highest percentage of unique native species for warm water marine fishes anywhere on earth.

Thanks to our living reef, Hawaii consistently ranks as one of the top tourist destinations in the world...

Our reefs form sandy beaches that are ranked among the top beaches in the world.

Market research indicates that participating in diving and snorkeling activities ranks as one of the top five activities for our visitors from the West.

Our reefs consistently rank as one of the top scuba diving destinations worldwide in dive magazine surveys.

Thanks to our living reef, the native Hawaiians were incredible watermen and reef stewards...

The reefs provided sustenance, as well as a basis for leisure. From fishing to sailing to surfing, many of the activities pursued by the ancient Hawaiians are still popular today. Board surfing is Hawaii’s premier contribution to the world of ocean recreation.

Early Hawaiians recognized the importance of corals and the coral reef as a major component of the building blocks of our Islands. The coral (Ko’a) is mentioned in the beginning versus of the Kumulipo, the creation chant of Hawaii. The coral polyp was the first creature to emerge during creation, according to Hawaiian mythology.

The importance of the reefs was not lost upon Hawaii’s earliest residents; in fact, corals were often presented as offerings during religious ceremonies.

An intimate knowledge of the reefs and the protection and maintenance of reef resources was, is, and will continue to be central in the Hawaiian way of life.

Source: Hawaii’s Living Reef program

_{(Photo courtesy of The Away Network)}   

Even if you don't live near a reef, you can help protect coral reefs in the U.S.A. and around the world.

This list is from the National Oceanic and Atmospheric Administration's (NOAA) Coral Reef Conservation Program.

Educate yourself about coral reefs and the creatures they support. How many different species live in reefs? What new medicines have been developed from reef organisms? Participate in training or educational programs that focus on reef ecology. When you further your own education, you can help others understand the fragility and value of the world’s coral reefs.

Be a wastewater crusader! Make sure that sewage from your boat and home is correctly treated.

Support organizations that protect coral reefs. Many groups have coral reef programs, and your support will make a big difference.

Don’t overuse chemically enhanced pesticides and fertilizers. Although you may live thousands of miles from a coral reef ecosystem, these products can end up in the watershed -- the area that drains to a common waterway, such as a stream, lake, estuary, wetland, and ultimately, the ocean.

Volunteer for a reef cleanup. You don’t live near a coral reef? Then consider visiting a coral reef on your next vacation. Spend an afternoon enjoying the beauty of one of the world’s treasures while helping to preserve it for future generations.

Be an informed consumer. Only buy marine fish and other reef organisms when you know they have been collected in an ecologically sound manner. Ask store managers where the organisms come from and how they were collected. Does the country have a management plan to insure the harvest was legal and sustainable over time? For more information on how to find sustainably harvested reef fish, go to www.aquariumcouncil.org.

Visit your local aquarium or zoo. Ask what they are doing and how you can help conserve our coral reefs. The answer may pleasantly surprise you. Visit the American Zoo and Aquarium Association to find a zoo or aquarium near you.

If you dive, don’t touch! Take only pictures and leave only bubbles. Keep your fins, gear, and hands away from the reef, as this contact can hurt you and will damage the delicate coral animals. Stay off the bottom because disturbed sediments can smother the corals.

Support reef-friendly businesses. Ask what your dive shop, boating store, tour operator, hotel and other coastal businesses are doing to save coral reefs. This is especially important in coastal areas with reefs. Let them know you are an informed consumer and care about reefs.

Recycle. This helps keep trash out of the oceans and also out of landfills where it can have an adverse impact on the water quality of our rivers and oceans.

Become a volunteer monitor! If you live near the coast, participate in community coral reef monitoring programs.

Report dumping or other illegal activities. Help be the eyes and ears of the reef! Your involvement can make a big difference.

Be a marine debris crusader! In addition to picking up your own trash, carry away the trash that others have left behind. More than just an unsightly nuisance, beach litter poses a significant threat to the health and survival of marine organisms, which can swallow or get tangled in beverage containers, plastic bags, six-pack rings, and other debris.

Hire local guides when visiting coral reef ecosystems. This will help you learn about local resources, and protect the future of the reef by supporting the local economy.

Don’t anchor on the reef. If you are boating near a coral reef, use mooring buoy systems when they are available.

Participate in the Great Annual Fish Count. What better way to enjoy your vacation than snorkeling or diving in America’s coral reefs? The Fish Count helps scientists better understand coral reef fish populations.

Respect local guidelines when you visit a reef. Help keep coral reefs healthy by respecting local customs, recommendations, and regulations. Ask local authorities or your dive shop how to be a reef-friendly tourist.

        

(Photo courtesy of The Coral Kingdom)
Clown fish live symbiotically with sea anemones.
Photo credit: Andy Bruckner at NOAA

(Coral Fiji, Photo courtesy of The Away Network)