Coral Reefs Are Threatened
Mass bleaching caused by climate change continues to threaten coral reefs all over the world. Do you know what causes these problems? If you guess Global Warming, you are certainly correct although there are a lot of other major contribution beside the heat. Find out what and how Coral Reefs are bleached and threatened:
We are getting longer and hotter summer. The climate is changing and is heading down a road that can destroy some of the most beautiful nature we know today. Marine scientists, divers and many others are starting to worry about the current global coral bleaching event. Temperature stress might be the biggest threat and main cause of the bleaching, and as climate change in general and El Niño events pressing the temperature even higher, the future of our beloved corals is not quite so bright. But on the bright side there is a lot you as a diver can do to keep the coral reef alive, and first step in the right direction start with a little education within the threats that are facing the reefs.
When the corals get stressed
A lot of things can stressed out the corals, because they are very sensitive and what seems as small impacts to us humans, can be fatal stress factors for the corals. Pollution, sedimentation, disease and physical impacts like a touch from a diver can be very harmful to the corals because of the stress it causes. Mostly we associate the bleaching of the animals with temperature stress, which can be cause if the surrounding waters are higher or lower than their optimum range, 68 to 89 F (20 to 32 C).
If conditions become too hot or too environmentally stressful in another way, the coral will expel the zooxanthellae. Zooxanthellae provide coral with their rich colors and 80 percent of their nutritional requirements. When corals become too stressed, their mutually beneficial relationship with photosynthetic algae (zooxanthellae), which lives in their tissues, gets a bit rocky. Without these algae, the coral polyp is transparent and we can see its white calcium-carbonate skeleton, which is what we mean when we say a coral is “bleached”.
Coral animals that appears bright-white is still alive, however on an extreme diet. The reason why it is stressed out is caused by the corals ability to catch food, when corals are bleaching they are only able to catch 20 percent of the needed food. If the problem is solved in time, coral will accept zooxanthellae back into their tissues and slowly turn back into a beautiful coral. However if the stress is not removed in time, the coral will die and the body will be overgrown with algae. The algae will cause problems by covering the skeletons and they make it impossible for new coral recruits to land on the coral and live. If this is not a onetime event and keeps happening we will start seeing to see an ecological shift from coral to algae-dominated reefs that house much lower biodiversity.
As divers, let’s make sure that we are diving responsibly. We will talk about how to prevent hurting the coral reefs even more on our upcoming posts. In the mean time, make sure you check our diving sites here. We’ll show you the world underwater and will make sure that your trip is sustainable.