Coral Reef of the Caribbean Sea

Coral reefs along with the rainforest are among the most productive ecosystems in terms of biomass and biodiversity, both develop in the tropical and inter-tropical zone of the Earth. Corals are usually near the shore where the waters are clear and the sea bottom shallow (less than 163 feets depth), the temperature is warm (60 to 82°F), salinity is high and there is abundance of nutrients in suspension like plankton. Coral reefs are constantly growing and the calcareous skeletons are deposited by animals and live in symbiosis with an algae. The calcareus squeleton have been accumulated for thousands and even millions of years so it is considered the coral reef a very stable ecosystem, species diversity, well adapted and with a high level of internal symbiosis.

The location of the coral reefs is between the open sea and the coast so they are a protective barrier against the waves and sea currents for ecosystems that are behind him as Thalassia meadows, mangroves and land.

In the Caribbean Sea coral reefs are present on all coasts, with a lesser pesence in the coast of Venezuela, Honduras, Nicaragua and Costa Rica. Coral reefs along with mangrove forests are the great builders of new land on the islands of the West Indies.

The diversity of biological species around these living rock formations, is the richest known both for its diversity and abundance. It is a notable difference between the reef and sandy bottoms that surround it.

Coral polyps are embedded within a calcareous structure generated by themselves by fixing calcium carbonate dissolved in water, as the polyps die calcareous remains in place until they are degraded or serve as a substrate to other colonies. Coral sand and other calcareous debris is removed by currents to other places where it is deposited and accumulates with the appearance of coral islands, such as the Archipelago Los Roques.

Eventually, the established mangrove with its root system retains more efficiently sediment and sand and thus continues forming the islands, it is also possible that when the dead corals exposed above sea level begins to be colonization by terrestrial plants.

Stony corals are the main contributors to the ecosystem substrate; however along with them they are also of great importance the calcareous algae, who also makes an important contribution to the calcareous material of the reef. There are also many other organisms such as molluscs, crustaceans, sea urchins, starfish, etc. that in greater or lesser degree generate calcareous material which is deposited on the reef after his death.

Coral Reefs have a symbiotic relationship with a photosynthetic green algae also called zooxanthellae that live in the tissues of the polyp. The zooxanthella converts sunlight, carbon dioxide and water into oxygen and carbohydrates of which polyps feed. In compensation the polyps provide the zooxanthella with protection and the necessary compounds for the photosynthesis. Depending on the color of the zooxanthella is the color of the polyp which may be green, orange, red, purple or yellow. Polyps feed overnight, extending its tentacles to capture plankton passing in front of them suspended in the waters.

Part of the coral reef fauna have their activity during night time, especially invertebrates. While during the day the abundant photosynthetic flora of algae perform its function by absorbing sunlight and transforming it into food for shoals of fish that feed on algae, plankton or detritus.

In the Caribbean Sea some coral species are more abundant than others and thus contribute in varying degrees to the reef structure. The most common species are Elk horn (Acropora cervicornis), Deer antler (Acropora palmata) and Brain coral (Faviidae spp).

On the Coral Reefs there are countless life form among the most visible are the gorgonian (Gorgonia mariae), algae (Padina jamaicensis), sponges (Aplysina fistularis) and many more.