Our Fading Corals

Our Fading Corals

Corals can exsist as either individual polyps or in colonies and communities. There is hard coral, which produces a ridgid skeleton made of calcium carbonate in crystal form and then there is soft coral which does not produce a skeleton of calcium carbonate. Reef building corals get up to 90 percent of the energy they need from their symbiotic algae, but most corals also catch and consume live prey. When it is time for it to capture its food, a coral plyop will extends its tentacles and wave them throuh the water where they will encounter small fish, zooplankton, and bacterioplankton. The surface of each of the coral's tentacles has thousands of stinging cells referred to as nematocysts. When the prey pass by, the stinging cells fire and paralyze or kill the prey and the coral brings it to its mouth to eat it. Adult polyops develop eggs or sperm within their bodies. Somehow they know when to release them so that the sperm and eggs meet up in the water and produce the larvae which are called planulae. Most planulae dont't survive, but if they do they attach to something before developing into polyps. Most of the reef-building corals contain photosynthetic algae called zooxanthellae. Corals and the algae have a mutalistic relationship.The coral provides the algae with a protected environment and things they need for photosynthesis and the algae produce oxygen and help the corl to remove waste. Since the algae is a plant, it requires sunlight in order to perform photosynthesis and to be able to grow. This being said, coral reefs need to be at water depths where the sun is able to penetrate the water. Corals live in tropical and semi-tropical waters. Reef building corals cannot tolerate water temperature below 64 degrees Fahrenheit. Typically, they grow in waters between 73 and 84 degrees Fahrenheit. Reef coral live in seawater salinities ranging from 25 to 42 percent. If the pH of the water gets to high, then the corals living in the water will die. Corals need to live in water that is clear and that moves. The water needs to be clear so that the sunlight can go through the water to reach the coral. The water needs to move as well so that the tentacles of the coral can move so that it can catch its prey.

Corals support more species per unit are than any other marine environment. Many species live in and around the coral. Many drugs are also being developed from coral reef animals and plants. Possible cures for cancer are being found from these organisms. Coral reefs are very diverse environments. This being said, there are many trophic levels present in coral reef. Primary producers form the basis of the ecosystem. Some of the primary producers include photoplankton, coralline algae, and seaweed. Some of the primary consumers include zooplankton, gatropodsm and sponges. Secondary consumers include butterflyfish and coral guard crabs. All of these plants and animals are interconnectd in ecological relationships. Predation and Competition are only some of the ecologial relationships present within these corals. There are many benefits to coral. Other than the fact that they provide a home to thousands of animals and plants, they are economically beneicial. We recieve a lot of money from the corals being tourist attractions. Billions of dollars are made off of the reefs each year. Changes in abiotic factors such as climate have been named one of the greatest threats to coral. As the temperature in the water rises, mass bleaching as well as infectious disease outbreaks are more likely to occur. These diseases are also a large threat to the coral reef population. Wheather related damage also occurs a lot to the coral. Things such as hurricanes and cyclones can break apart and/or flatten the coral reefs. There also human caused threats. Things such as fishing around the corals can not only damage the coral reefs, but they can also destroy the animals and plants that surround the reef.

Benefits and Threats

Features and Abiotic Factors

The Great Barrier Reef is the world's largest coral reef system. It is composed of over 2,900 individual reefs. This Barrier Reef is located on Australia's north-eastern coast. The Great Barrier Reef has experienced mass coral bleaching in the past. The last mass bleaching event occured in 2002 and 60% of the population were affected by the event. It has been recorded recently that coral diseases are responsible for 6.5 percent of the coral death within the reef. This being said, coral diseases have not caused as much damage on the Great Barrier Reef as they have on other coral reefs around the world. Some of the diseases that have spread around the Great Barrier Reef include: white syndromes, black band disease, and brown band disease. The condition of this reef is vital to the thousands of animals that live in the reef. It is also important to the people because without the Great Barrier Reef, a huge source of income will be lost. The reef is a huge tourist attraction and without it there the businesses will suffer greatly. The health of this coral reef system is very important for many reasons and it should be considered a high priority.

Great Barrier Reef