the process whereby coral turns white as a result of losing the microscopic algae (zooxanthellae) that live in coral's tissues, loss caused by exposure to water temperatures 1-2° Celsius higher than the mean averages at the warmest time of year; global warming is one cause of higher temperatures
a phenomenon occurring when corals under stress expel their mutualistic microscopic algae, called zooxanthellae. This results in a severe decrease or even total loss of photosynthetic pigments. Since most reef building corals have white calcium carbonate skeletons, the latter show through the corals' tissue, and the coral reef appears bleached. [JVG
Warming water may affect the natural balance of the marine ecosystem. In the case of coral reefs, warming water may cause bleaching of the living algae followed by death of the coral skeleton. If coral reefs bleach and die, many species will lose valuable spawning grounds and habitat.
Coral bleaching occurs when sea temperatures become too hot. The coral polyps (tiny animals) growing on the coral skeleton contain microalgae. These microalgae give the coral polyps their colour, hence the colourful corals. But when the sea water becomes too hot, the coral polyps become stressed, and they eject the microalgae, causing the corals to turn white. As the microalgae provide the coral polyps with most of their food, bleached corals are actually starving to death. If the sea temperatures cool quickly enough, the microalgae can re-colonise the polyps and the coral can recover its health and its colour. But if the sea stays hot for too long, the corals will die. Back up
the release of the symbiotic colored algae normally living within coral animals, which occurs when coral animals are stressed (by high temperatures, for example) and makes the coral appear whites
A phenomenon in which corals under stress (e.g., by elevated water temperature) expel their mutualistic algae (zooxanthellae) in large numbers, or the concentration of algal photosynthetic pigments decreases. As a result, the corals' white skeletons show through their tissue and they appear bleached.
the exposure of the white calcium carbonate skeleton of the coral because of the loss of the symbiotic algae. Coral bleaching can be caused by disease, excess shade, increased levels of ultraviolet radiation, sedimentation, pollution, salinity changes, or increased temperatures.
A condition of corals when photosymbiotic organisms, e.g., dinoflagellates such as zooxanthellae, are forced to leave the host coral animals.
n: The loss of color from a coral as it expels its zooxanthellae-usually a stress response.
Situation where coral lose their colorful symbiotic algae. Thought to be caused by unusually warm water, changes in salinity of ocean seawater, or excessive exposure to ultraviolet radiation.
The corals that form the structure of the great reef ecosystems of tropical seas depend on a symbiotic relationship with photosynthesizing unicellular algae called zooxanthellae that live within their tissues. Zooxanthellae give coral its particular coloration, depending on the clade living within the coral. Under stress, corals may expel their zooxantheallae, which leads to a lighter or completely white appearance, hence the term "bleached".
