What are the effects of coral bleaching?
Mass bleaching of corals is now the biggest threat to the survival of coral reef ecosystems. Coral polyps harbor symbiotic algae called zooxanthellae, which provide the necessary nutrients for reef building corals to calcify reef structures. When a coral bleaches it loses its symbiotic zooxanthellae and will die within a short period of time unless it regains it. Many hypotheses exist as to the cause behind coral bleaching, but the strongest evidence points to elevated sea surface temperatures as being the main catalyst. It is hypothesized that stress induced from pollution, ultraviolet radiation, and changing salinity also play a role in the extent of coral bleaching. With the current sea surface temperature warming trend, likely due to global climate change, along with the apparent increase in frequency and intensity of El Nino events, coral reefs, as we know them, are at an extreme risk of becoming extinct within the next 50 years.
