Corals are invertebrates, or animals without a backbone. Their "bodies" are tubes attached to a rock on one side with an open mouth surrounded by stinging tentacles on the other. Corals are part of a larger group of animals that have stinging tentacles called Cnidaria. This group also includes jellyfish! Corals have a symbiotic relationship with algae, meaning these two organisms work together: the algae provides the coral with food, oxygen, and waste removal, and in exchange, the coral provides the algae with a place to live. It is the algae living on the coral makes the reef so colorful!
Coral bleaching is when stress from increased water temperatures and UV radiation causes corals to kick out the microalgae living on them, causing the coral no longer to be colorful. Without algae to provide the coral with food, oxygen, and waste removal, the coral slowly begins to die. This is a natural process that can occur for short periods during the summertime when the water heats up and the sun is brighter. Unfortunately, due to global climate change, ocean temperatures are rising causing this coral bleaching to persist, preventing the reefs from fully recovering each year. This is concerning because the reef is home to 25% of all known marine species, so the death of the reef puts many species at risk! Seeing the beauty of the reef firsthand showed me how important it is to protect our world's resources!
