----------STOP NUMBER 1--- Reefs are home and nursery for almost a million fish and other species, many of which we rely on for food; some of the Earth's most diverse living ecosystems; full of new and undiscovered biomedical resources that we've only just begun to explore; important protection for coastal communities from storms, wave damage and erosion. However, they are being carelessly destroyed.
----------STOP NUMBER 2--- Coral reefs consist of many diverse species of corals. These corals in turn are made up of tiny organisms called polyps. The structure of the polyps and the skeleton of the coral is a rather simple combination. A polyp is made up or two cell layers: the epidermis and the gastrodermis. ((1.)) The skeletal wall around each polyp is called the theca. the coenosarc (the coral tissue that stretches over the surface of the coral between the polyps). A coral colony may consist of thousands of polyps.
----------STOP NUMBER 3--- There are two types of corals: perforate and imperforate. Perforate corals have porous skeletons with connections between the polyps through the skeleton. Imperforate corals have solid skeletons. ((2.)) There are three basic kinds of coral reefs in the Caribbean: fringing reefs, barrier reefs and atolls. Fringing reefs are coral reefs that grow in shallow waters and border the coast closely. Fringing reefs consist of several zones that are characterized by their depth, the structure of the reef, and its plant and animal communities. These regions include the reef crest (the part of the reef the waves break over). Barrier reefs are reefs that are separated from land by a lagoon. These reefs grow parallel to the coast and are large and continuous. Barrier reefs also include regions of coral formation that run parallel to the coast and protect the land from waves. The third type of coral reefs are atolls. Atolls are annular reefs that develop at or near the surface of the sea when islands that are surrounded by reefs subside.
----------STOP NUMBER 4--- Coral reefs are among the most diverse and productive communities on Earth. They are found in the warm, clear, shallow waters of tropical oceans worldwide. ((3.)) Reefs have functions ranging from providing food and shelter to fish and invertebrates, which are a healthy food source, to protecting the shore from erosion. Coral reefs produce many nutrients used in medicines.
----------STOP NUMBER 5--- Corals can obtain food in a variety of ways. ((4.)) Reef-building corals rely on the photosynthetic products of zooxanthellae for the majority of their nutrients. However, corals also capture zooplankton for food. They lure the plankton onto their stinging tentacles and bring the food to their mouths. Most corals feed at night. This may be because night is when the zooplankton travel into the water column and become available for capture.
----------STOP NUMBER 6--- Corals exhibit sexual and asexual reproduction. ((5.)) The coral colony expands in size by budding, in which the new bud forms from the oral discs of the old polyp, or the new polyp forms from the base of the old polyp. A common type of asexual reproduction in corals is by fragmentation. Broken pieces of corals that land on a suitable substrate may begin growing and produce a new colony.
----------STOP NUMBER 7--- Coral reefs provide habitats for a large variety of organisms. These organisms rely on corals as a source of food and shelter. crustaceans such as shrimps and crabs depend on corals for shelter. Fish depend on corals for protection against predators. There are many other species of fungi, sponges, sea worms, crustaceans and molluscs that bore into coral skeletons. Other organisms that inhabit the coral reefs include sea urchins, jellyfish, oysters, clams, turtles, and sea anemones. ((6.) On average, each Eternal Reef produces about 400 lbs.of bio-mass (animal or plant life) each year and have an expected life of at least 500 years.
----------STOP NUMBER 8--- Corals and coral reefs are extremely sensitive. Slight changes in the reef environment may have detrimental effects on the health of entire coral colonies. These changes may be due to a variety of factors, but they generally fall within two categories: natural disturbances and human disturbances. ((7.) Although natural disturbances may cause severe changes in coral communities, human disturbances have been linked to the vast majority of decreases in coral cover and general colony health when coral reefs and humans occur together.) Humans hurt the reefs in a number of ways. One of the greatest threats to coral reefs is human expansion and development. As development continues to alter the landscape, the amount of freshwater runoff increases. This runoff may carry large amounts of sediment from land-clearing areas, high levels of nutrients from agricultural areas or septic systems, as well as many pollutants such as petroleum products or insecticides. ((8.) These nutrients and pollutants can either cause a lack of sunlight and bleach the corals or they can be absorbed into the corals and cause them to grow too large therefore making reefs become overcrowdedcrowded.) As this population increases, so does the harvest of resources from the sea. Due to overfishing, reef fish populations have been greatly decreased in some areas of the world. The removal of large numbers of reef fish has caused the coral reef ecosystems to become unbalanced and allowed more competitive organisms, such as algae, which were once controlled by large fish populations, to become dominant on reefs in many regions. Proffessional diver also collect healthy pieces of coral to sell to tourists. Parts of reefs are also destroyed by boat anchors and gas leaks.
LINKS
Coral Reef Hotlink for Question 9
Coral Reef Hotlink for Question 10
CLICK HERE TO SEE THE PICTURES
