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"Coral Bleaching"

(Image shows healthy and threatened corals)

environmental issues One of the many affects of 'Global Warming' is 'Coral Bleaching'. This is one of the most devastating threats our coral reefs face. Coral bleaching is exactly what it sounds like, the coral turns white and subsequently dies. Coral reefs are the most sensitive ecosystems on earth. If the reef is subjected to long term temperature change (increase) this creates enormous physiological stress and the critical balance is then disrupted. Corals and small animals live in immense colonies harvesting nourishement and energy from microscopic algae which inhabit their cells by the thousands. The algae is a golden brown and combined with other pigments is responsible for the corals spectacular appearance.

Fragments of coral sand and limestone make up the reef. Over hundreds of years in the making a framework is constructed, hence the coral reef is born. During its time hundreds of animals and plants attach themselves to the structure creating an incredible eco-community.

These reefs are very dependent on temperate sea surface conditions. 64 degrees F or more. As global warming has increased dramatically in the past decade the rise in ocean temperature is taking its toll on the coral reefs. This physiological stress upsets the critical balance and the symbiotic relationship with the algae is lost. As mentioned algae is one the sources of the corals color and when it is lost the condition is known as coral bleaching. Scientists have reported coral bleaching in at least 60 countries and island nations worldwide. This also includes the Caribbean.

Coral Reefs have a tremendous value. Substantial income is derived from tourism and about half of the potential pharmaceuticals being explored are from the oceans.

Aside from global warming, coral bleaching is also caused by pollution, coastal runoff, silt and sand. With silt smothering the reef and blocking sunlight, coral polyps will get rid of their plant partners. Without the plants the polyps lose their color, and more importantly, their ability to build more reef.

I have just recently finished my inspection of St. Maarten's reefs and my analysis is anything but encouraging. Over 85% are covered in silt and sand. Most all of the reefs have one form or another of coral bleaching. These are the rainforests of the ocean, and slowly but surely they are vansihing before our eyes.

Remember, when a reef is lost it means a higher probability of extinction of marine life!