What is coral bleaching? Why does it happen?

What is coral bleaching? Why does it happen?

coral bleaching
 Image credit: Wikipedia via CC license

Coral bleaching, the phenomenon, the event that has brought scientists from all around the world together to discuss a single question- what is happening to our coral? Climate change skeptics and environmental downfall contributors have no other option than to acknowledge the reality of this current mass global issue.

An event that has been trending and turning heads from all over, even reaching world news. It has made its way to fame and has quickly gotten the attention of the human race- but do you really know what coral bleaching is?

So what is coral?

Looking at coral from its outward appearance, it can be disguised as a simple being that has no other purpose than for fish to inhabit and feed on. Some even mimic a rock substance. It is only when you look within that you realize that it is not a simple being at all.

bleached coral

Coral colonies are made up of tiny, yet extraordinary polyps that resemble sea anemones. An algae called Zooxanthellae, or Zoox,  benefits the coral by living inside the polyps and photosynthesizing. This provides the necessary nutrition a coral needs to be able to be, well, coral.

Benefits of coral

Scientists are fascinated with the advantages that coral provides. In reality, these ancient and complex animals are what millions depend on for their survival. Some benefits of the reef include protection from tropical storms and waves. Also tourism, food, habitat and protection for many marine species, and even medicine. Imagine what would happen if we were to lose all of this due to the recklessness of our own generation? Well, the truth is that we already are on our way to doing so.

Our environment is sufferering

When you take a step back from the normality that our society has been convinced is sufficient and ideal, you will be shocked. As humans we have developed this hunger for more. We can’t get enough whether its money, power, food, clothes, etc. Then we are basing these needs off the idea that we will never run out, thus mass producing. It is only when we wake up from this false mentality that we can see what we are doing to our planet. The environment has been silently suffering from our carelessness for a long time. But it is finally grabbing our attention through natural disasters such coral bleaching. 

a bleached coral reef
Coral bleaching at Molokini Crater

Our carbon pollution is affecting our climate worldwide, especially our oceans. With life as fragile as coral, the rising temperature of only a few degrees can dramatically alter their ability to function. This can almost certainly lead to fatality, or otherwise known as bleaching. Car pollution, factory pollution, mining and burning of coal, and other destructive actions of man are collectively working together to kill coral reefs by stressing them out.

Like humans who react to fevers, the coral reacts to heat by expelling the zooxanthellae. The disruption of the zoox and coral relationship causes the coral to starve. This is due to the lack of nutrients obtained through photosynthesis. They then turn the color white we so famously see, giving it the name “bleaching”. Although most believe that a coral is dead once it has turned this holy white, it is actually still alive. It has the potential to recover. It is only once the tissue is extracted and rotting from the coral that it is officially too late. 

Other factors like overfishing, pollution, and sunscreen, work as a team to cause coral bleaching on our coral reefs. If we continue to go down this wasteful and harmful path, we will only increase the severity of coral bleaching. A species that has survived for centuries is now depleting in only a few years due to the intensity of our ways. It can take decades for a reef to recover and less than a decade to destroy it. If we continue our mass burning of fossil fuels and increase our carbon pollution in the atmosphere, these severe bleaching events will continue annually. Coral is vital to life on Earth and the mass bleaching events are a cry for help. It is now up to us to ensure that the coral reefs are not gone for good.

So what can you do?

A few ways to help save our reefs and our planet:

Transportation (biking, walking, bus)

Reef Safe Sunscreen

Reduce, Reuse, Recycle

Speak Up

Reduce Runoff in our oceans

Eat sustainably

Keep feet/fins off of the reef