Many coral reefs all over the world are being destroyed. We can all protect the coral reefs by remembering that they are created by a fragile and delicate animal. Coral is a stony substance that is made of the skeletons of certain kinds of tiny sea animals called polyps. Polyps build the coral. They are little animals that make up the coral reef with their skeletons. Reefs and small islands featuring coral are always found in tropical seas and oceans. Coral reefs vary in shape, size, and color. They are homes to many different animals such as sponges, crabs, lobsters, and many small fishes.
What things do coral need to survive?
Coral reefs need three things to survive. They need warm water, sunlight, and clear, shallow waters. Coral will not grow in waters that are lower than 68 degrees Fahrenheit (20 degrees Celsius). Sunlight and clear, shallow water is needed so that the zooxanthellae in their tissue can photosynthesize. The zooxanthellae transfers some food energy directly to the coralís polyps. If waters are too deep or too murky, the zooxanthellae will not get enough light to photosynthesize. Photosynthesis is a process that plants go through to make their own sugars and starches. Even though coral is not a plant, it still photosynthesizes to store the energy that it gets from the sugar and starch. This is why you usually donít find coral below 100 meters (330 feet) deep.
What threats are coral reefs facing?
Coral reefs are facing many threats, both by nature and mankind. Hurricanes and storms are quickly destroying large portions of many coral reefs. Other sea animals such as fish, snails, worms, and starfish are eating many areas of the reefs. Humans also have a huge impact on coral reefs being destroyed. In a number of ways, we are destroying the reefs without realizing it.
Pollution is one way people are destroying coral reefs. Pollution can kill reefs from poisons and heavy metals. The pollution enters the ocean by oil spills, acid rain, dumping of hazardous waste, exhaust pollution from boats, jet skis, and many more sources. The pollution enters the coral through the polyps, and the heavy metals from the pollution can kill the animals. When the polyps are killed, it harms the coral because they are what build the coral. Without them there is no new coral. Everything dies after that. This happens because the polyps are the coral. If there were no polyps or maybe even fewer polyps, the coral would die because there would be an empty part in the coral. The polypsí skeletons are what gives the coral its jagged edges and rough surface.
Global warming is another way we are harming coral reefs. Global warming is the warming of the surface of the earth or when the earthís temperature rises to a temperature that is not normal. Oceans cover over 70% of the land on earth. This means there is a lot of heat created by global warming that is stored in the oceans. This causes the water to evaporate, which leaves the coral above the water. The coral will not be able to breathe above the water and will eventually die.
More than a quarter of the earthís coral reefs have been destroyed by pollution, global warming, and poor fishing practices. Fishermen may use spear guns, which can damage the coral, commercial poisons, and sometimes dynamite for fishing. Overfishing in the coral reef area can cause damage to food chains around the reefs also. We already have a huge effect on coral, but it takes a while before our actions harms the reefs. Our actions won't stop until we do something about it.
Did you know that coral has an important partnership with a certain algae? This algae absorbs and converts sunlight into energy. This energy is needed to feed the life found in a reef ecosystem. Pollution or climate change is a common cause of the loss of the algae. Because of this, the reef is being left "bleached" and not able to produce energy from sunlight. You can tell when a reef is bleached because large areas of the reef turn white. This will affect the food chain because it will kill the polyps that live in that area. There will then be fewer polyps, and whichever larger animals eats these will not be able to eat. This will cause them to have to change food, and by doing this they may die out and put a dent in the food chain.
When people damage coral reefs, they are also disturbing the home and food of other animals. Many animals under the sea have made the coral reefs their place to settle. When the coral is destroyed, then these animals have no place to live. When the coral is destroyed, it also affects the food that animals eat. It is not a good thing for the animals to eat the coral, but the animals still need food to eat, so they do that anyway. When the coral is killed, the animals that eat the polyps have less to eat, so they will have to change foods. This is not always good for the animal, and they may eventually die.
Brown seaweed destroying coral reefs in Florida
Over the past fifteen years, a species of brown seaweed has been suffocating Floridaís fragile coral reefs. This type of seaweed is called Dictyota menstrualis. It has been growing very large in the coral reefs of Florida, the Bahamas, and the Caribbean. In some areas of the reefs, the seaweed covers from 30 to 70% of the ocean bottom. This seaweed just grows and grows, killing everything in its way. The seaweed tangles itself around the coral. It tightens up to the point where the polyps cannot breathe and will suffocate.
How can we save the coral?
It may be hard to imagine all the bad things we have done to coral reefs, but there are also things we can do to save the coral reefs. When you go to an ocean do not touch, sit on, or stand on the coral. We can try to help decrease pollution by not using lights, TVs, radios, washing machines, dryers, hair
dryers, cars, microwaves, air conditioners, video games, and dish washer as much as we do now. If you go fishing in an ocean where there is coral, donít use objects or chemicals that will harm or damage the coral reefs and any other things in the ocean.
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