What Is Coral
Coral is an invertebrate animal that is related to jellyfish and anemones. It lives in salt water, typically in warm tropical oceans. Coral polyps are very small—usually only a couple of millimeters in diameter—and they cluster together in large groups called colonies.
When these coral polyps die, they leave behind their hard limestone skeletons, which eventually form coral reefs.
Coral Reefs
Coral reefs are large underwater structures made up of the skeletons of dead coral. These reefs can be found in tropical and subtropical oceans around the world.
Importance of Coral Reefs
Coral reefs are important for many reasons. They provide a home for 25% of marine life, including fish, mollusks, and crabs. They also protect coastlines from erosion and storm damage.
Coral reefs are often referred to as the tropical forests of the sea because they are habitats for such a large diversity of plant and animal life.
Coral reefs are also a major source of food for the people who live near them. In fact, it is estimated that coral reefs provide food for about 500 million people around the world.
Types of Coral
There are two main types of coral: hard coral and soft coral. Hard coral is the type of coral that forms reefs. It has a hard limestone.
Soft coral does not have a hard skeleton. Instead, it is made up of a flexible material called gorgonin.
Coral colonies can be either encrusting or free-living.
Encrusting coral colonies attach themselves to rocks or other hard surfaces. Free-living coral colonies do not attach themselves to anything.
Coral Temperatures
Coral prefers warm water temperatures, typically between 68 and 86 degrees Fahrenheit. However, some types of coral can survive in cooler waters.
Threats to Coral Reefs
Coral reefs are under threat from global rise in temperatures, pollution, and overfishing.
Global warming is causing the ocean to warm. This causes coral bleaching, which is when coral loses its color. Coral can die if the water gets too warm.
Pollution from things like sewage and fertilizer can also harm coral. These pollutants can cause algae to grow on the coral, suffocating it.