Coral reef bleaching occurs when zooxanthellae are released by the corals to help regulate the amount of zooxanthellae that are present in the reef. The process of releasing the zooxanthellae is naturally occurring in coral reefs and helps them to regulate their environments. Coral reef bleaching occurs when the coral reef releases too much of the zooxanthellae; by releasing too much the coral reef proceeds to die and loose its color, this is where the name coral reef bleaching comes from. Coral reefs and zooxanthellae have a mutual relationship; this means that they both depend on each other for survival and that they both help maintain stable living conditions for each other. The release of the zooxanthellae by the coral reefs can be caused by a few factors. When too much carbon dioxide or ammonium particles are present in the environment, the coral reefs have been know to start this expulsion or bleaching process and to completely die off. This process has been observer across the world but most cases are found in the Caribbean Sea. Global warming is another factor of coral reef bleaching due to elevated water temperatures that speed up the process. More must be done to help discover the many factors of coral reef bleaching so that it can be stopped and so that we may protect the valuable coral reefs across the entire earth.