What is Coral Reef Biomes? | Types, Definition, Structure, Function & Facts

What is Coral Reef Biomes?

Coral reefs are one of the major marine biomes. Despite being a relatively small biome, about 25% of known marine species live in coral reefs.

What is a Coral Reef?

At first glance, you might think coral reefs are made up of rocks, but they are actually living creatures. These organisms are tiny animals called polyps. Polyps live outside the reef. As the polyps die, they become hard and new polyps grow on top of them, causing the reef to grow.

Does the Coral Reef Eat?

Since polyps need to eat to live, you might think that coral reefs also eat. They eat small animals called plankton as well as algae. Algae get food from the sun by photosynthesis. This is why coral reefs form near the water’s surface and in clear waters where the sun can feed algae.

Where are Coral Reefs Located?

Coral reefs need warm, shallow water to form. They form near the equator near coasts and around islands around the world.

A significant portion of the world’s coral reefs are found in Southeast Asia and near Australia. The largest reef is the Great Barrier Reef located off the coast of Queensland, Australia. The Great Barrier Reef stretches for 2,600 miles.

Types of Coral Reefs

There are three main types of coral reefs:

Fringe Reef – Fringe reefs that grow close to the shore. It may be attached to the coast or there may be a narrow strip of water called a lagoon or channel between the mainland and the reef.

Barrier Reef – Barrier reefs develop farther from shore, sometimes several miles from shore.

Atoll – An atoll is an atoll that surrounds a lagoon. It started as a fringe reef around a volcanic island. As the coral grows, the island sinks into the ocean and only the atoll remains. Some atolls are so big that people live there. An example is the Maldives.

Zones of the Coral Reef

After a while, the reef grows in area. Each area is home to different types of coral, fish and ocean life.

Shore or Inner Reef Zone – This area is located between the ridge and the coast. Depending on the shape of the reef, the area can be teeming with life, including fish, sea cucumbers, starfish, and anemones.

Crest Reef Zone – This is the highest point on the reef and where waves break over the reef.

Fore or outer Reef Zone – As the reef wall descends, the water calms down. At a depth of about 30 feet, you will usually find the most densely populated part of the reef as well as a huge number of corals.

Coral Reef Animals

All kinds of animals live around a coral reef. This includes a variety of corals such as star corals, brain corals, column corals, cactus corals, and finger corals.

Some of the strangest and most interesting creatures in the world live here. Many animals cling to the reef that covers nearly every square inch. These include sponges, starfish, sea anemones, cucumbers, snails, and clams. In addition, there are many species of swimming fish, such as cuttlefish, sharks, lionfish, puffer fish, clownfish and eels. There are 1500 species of fish and 400 species of coral that live only on the Great Barrier Reef.

Coral Reef Plants

Most of the plants that live on coral reefs are seagrasses, seaweeds and seaweeds.

Why are the Coral Reefs Important?

Aside from beauty, a tourist attraction and an important part of planet Earth, coral reefs have a positive impact on many people around the world. This includes food from fishing, coastal protection against erosion and even medical discoveries like cancer drugs.

Are they in Danger?

Yes, coral reefs are slowly being destroyed. Because they grow at such a slow rate, they decompose faster than they can be repaired. Much of the damage is man-made, mainly from pollution and overfishing. Even tourists can damage coral reefs by standing on them, touching them or crashing into them with their boats.

Facts About the Coral Reef

Coral reefs grow very slowly. Large coral reefs grow at a rate of 1 to 2 centimeters per year. Some of the largest coral reefs are estimated to have taken up to 30 million years to form.

Some reef animals have symbiotic relationships. This means they help each other to survive. An example is clown fish and sea anemone.

Different types of corals grow in different shapes. Some are like mushrooms, others are like trees, fans, honeycombs, flowers and even brains.

The Great Barrier Reef is so big that it can be seen from space.

Some reefs have turned white because they shed their algae when the water is too salty or warm.