Tropical+Coral+Reef

Tropical Coral Reef



Described by Charles Darwin as oases in the desert of the ocean, coral reefs support over 25% of the world's known marine species. These rainforests of the sea are built up by calcium carbonate secretions from coral polyps. Most coral reefs lie between the latitudes of 30° N and 30° S, where the water temperature hovers around 26° C. Tropical reefs form in shallow waters no more than fifty meters deep. They cover about 284,300 square kilometers, which is less than .1% of the world's area covered by oceans. Coral reefs do not exist on the western coast of the United States as a result of upwellings; tropical coral reefs form in neither cold water nor nutrient-rich water.



Native Species The dwarf seahorse is one of many native species to tropical coral reefs.



Non-native/Invasive Species The Crown-of-Thorns Seastar is known to be an invasive species because it has populated the reefs and destroyed tons of coral.



Indicator Species Zooxanthellae is considered an indicator species. When Zooxanthellae concentration is low, less oxygen is produced and coral bleaching occurs.



Keystone Species Coral is a keystone species because without it, the area would not be considered a coral reef. The coral provides homes for many different species and therefore it is an extremely important part of the habitat.

Interspecies Species Generalized carnivores display interspecies competition. These large mouth fish, such as a Bluestriped Snapper, cover all areas of the reef at all times of the day and night.



Predator-Prey Relationship An example of this type of relationship would be a Striated Frogfish. This fish feeds on other fish by camouflaging itself on the bottom. This fish lures its prey by mimicking a worm in front of its mouth.



Mutualism Clownfish and Sea Anemones represent mutualism because the anemones provide the fish with a home, and the territorial clownfish, in turn, guard the anemone.



Commensalism Hawkfish and Fire Coral are examples of commensalism because the hawkfish waits for prey within the stinging coral.



Parasitism The Sacculina carcini barnacle finds a type of crab and enters the exoskeleton. The barnacles draws out nutrients, but the crab has no response. The crab just continues with his normal life.



Currect Event Article: []

Ocean Acidification Hits Great Barrier Reef by David Biello January 1, 2009
The growth of coral in the Great Barrier Reef has slowed by 13% since 1990. According to an article in //Science// magazine, the reason for this phenomena is global climate change. The hightened levels of CO2 are absorbed into the ocean and react with seawater to form a more acidic ocean. The acidic water prevents coral shell growth and speeds up coral deterioration. The rate of calcification is at its lowest in the past 400 years, potentially due to increased acidity.

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