Coral Bleaching

Scientists have warned that the corals in the Great Barrier Reef region are at a risk of being bleached due to the upcoming period of heat stress.

Great Barrier Reef Marine Park

The Great Barrier Reef Marine Park is located off the coast of Australia. It is spread over an area of 2,300km and is a World Heritage Site. It houses about 600 continental islands, 3,000 coral reefs, 1,625 types of fishes, 133 types of sharks and rays and 600 types of corals (both hard and soft types). The Great Barrier Reef accounts for nearly 10% of the world’s coral reef ecosystem.

Coral Bleaching

Coral bleaching is a process, that is deleterious to coral reefs, induced by stressful conditions. It is a process by which the corals expel the algae that usually reside in their tissues, causing them to loose color i.e. get bleached. Though this doesn’t mean that the corals are dead, it increases their vulnerability and consequently, mortality.

Causes

Coral bleaching is caused by unfavourable changes in conditions like temperature, nutrient levels and light exposure. One of the main factors causing coral bleaching is warming oceans. Eg: in 2005, half the Caribbean region’s corals were lost to coral bleaching induced by high temperatures. Cold waters can also cause bleaching. Other factors include illegal fishing, pollution by coastal run offs, coastal development, etc.