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Coral Crisis

Coral Reefs - the capitals of the underwater world. Covering less than 0,1% of the worlds Oceans, an impressive 25% of all known Ocean species inhabit coral reefs ! From space, it is even possible to see the worlds largest coral reef - the Great Barrier Reef ! Forming impressive hideaways and homes, serving as food and protecting coastlines from wave damages, among lots of other things - corals make up a vital part of the eco-system! But unfortunately coral reefs are under massive pressure due to climate change.

In this Editorial we will dive into this severe issue, and try to get a grasp around the consequences as well as the possibilities of a more positive future for coral reefs, and search for possibilities for us to be the change and contribute to a more sustainable future for coral reefs !

Photo by Daniel Hjalmarsson

According to a new report made by “Reefs at Risk Revisited” an estimated 75 percent of the worlds coral reefs are currently under threat.

But what exactly are they threatened by ? And what will happen ?

Lets start from the beginning…

At a glance, corals may look like plants, - but corals are rather complex animals. Related to sea anemones and jellyfish, - a coral polyp looks remarkable alike, - just tiny… Microscopic to be exact. But when placing a coral polyp underneath a microscope, - You will find the small animal looking exactly like a sea anemone.

Photo by Diogo Hungria

This coral polyp will build a skeleton around its vulnerable self. This skeleton can be soft or hard.

Hard skeletoned corals are the type of corals also called “reef builders”. Soft corals are the magical waving “plant-looking” corals, - often placed on top of reefs, gripping on to rocks and moving along with the currents.

When a coral builds up its home, - it needs to grow ! But the way corals grow is quite unique, - since the first coral polyp actually clones itself and thereby builds up a huge team, - consisting of hundreds, - sometimes thousands of coral polyps. Though growing is a fairly slow proces for corals.

A coral, depending on which specie, only grows 0,3mm - 2cm annually ! This slow growing process means that reefs and atolls (depending on their size) can take from 100,000 to 30,000,000 years to build up and fully form !

Coral polyps also needs help from others to exist… Since they are not able to find food all by themselves !

So corals has found their match made in heaven… They have partnered up with Algae.

With the interesting name “Zooxanthellae” (zo-uh-zan-thuh-lay), the plant-like organisms resides well protected inside the corals tissues.

In return the Algae provides the coral polyp with food by producing a type of waste product after the photosynthesis process - which insures the coral polyps existence.

Photo by Tomoe Steineck

Though the vital need for this relationship is also a part of the problem…

If the coral becomes stressed, the Algae will be thrown out, or move out, of the corals tissues.

This stress can occur from a lot of things : A rise or a fall in ocean temperatures, - pollution, too much sunlight, - among other things. So if the coral becomes stressed the Algae will simply leave its coral home, and find somewhere else to reside where it finds the temperature and stress-level more suitable.

This is the point where the coral becomes white…

The coral is not dead immediately - this takes longer time since the actually cause of death is due to starvation.

This color changing cause can be surprising. When looking at coral reefs, - You will find Yourself struck by all the beautiful colors corals wear.

But in fact, - these colors belongs to the Algae, since the coral polyp itself is almost see though, and the coral skeleton is white. This means, that when a coral is bleaching, it is the process in which the algae moves out of the coral, leaving it pale white.

But corals dont necessarily die when they have been bleached. It has been known that Algae returnes to corals, if the conditions quickly changes to the better. Then the corals will be fed by the algae once again and thereby the coral are saved from the bleaching event.

Unfortunately many coral bleaching events has uncured the last 20 years… In fact, research finds that severe coral bleaching is occurring five times more frequently that somewhat 40 years ago.

An example of a severe coral bleaching event is the 2015-16 bleaching in Christmas Island (Kiritimati).

The oceans became hotter, and remained hotter for about 10 months. This resulted in a mass death of corals - 90% of all the corals died, due to this long term shift in conditions.

Photo by Catrin Johnson
Wordwide, we have lost nearly 50 percent of all coral reefs over the past 30 years… And it is believed that approx. 90 percent of all the world corals will be dead in 2050.

When reading statistics, - it is almost impossible to find any glimmer of hope in this Coral Crisis… But there are some hope spots !

Super corals!

Scientists are working hard, working on breeding corals that can resist climate change. Scientists have gained successful results, - and as the Professor Madeleine van Oppen, from the Australian Institute of Marine Science and the University of Melbourne has quoted : “It is a story of hope, rather than saying ‘it’s all going to die and there’s nothing we can do about it’”.

Photo by Marek Okon

Though, many scientists remains skeptical about the super coral creation, - their argument being that super corals does not solve the coral bleaching crisis.

But knowing that conditions for coral reefs enviably will worsen the next 20 years, - working on breeding super corals might not be the worse to do.

As mentioned briefly earlier in this editorial, there are many important aspects of preserving and protecting coral reefs.

They are home to 25% of all known marine species, - they are the undersea rainforests and provides clean oxygen for humans as well, - they keep the marine eco-system at balance, they might also withhold the answers to many medical questions, and they provide livelihoods for more that 500 million people globally, - to mention but a few of the important reasons for doing our outmost to save coral reefs.

Studies have shown, that we, no matter how hard we work on reversing the rising ocean temperatures, lowering pollution etc. will loose more corals the upcoming years. So breeding and growing super corals, and “planting” these super corals among the stressed corals, - could be a part of the solution.

Photo by Tomoe Steineck

What can we do ?

You might be wandering…“Can I do anything to support a more sustainable future for coral reefs no matter where I live in the world ?”

The answer is simpel “Yes!”

Our oceans are connected - so wherever You are, - You will be able to contribute to corals future !

Here are five suggestions to what You can do to help corals :

1 Reduce, reuse and recycle as much as possible !

Pollution is harmful to the ocean in general, and by making sure to dispose your trash properly, - You can make sure that Your trash does not effect or harm coral reefs.

2 Become a Conscious Consumer

Research where Your seafood comes from, choose seafood that comes from aquaculture, - or choose fish caught sustainably by more controlled fishing methods

Read more at :

3 Use reef-safe sunscreen !

Some types of sunscreen contain chemicals that are harmful to marine species, - therefore mind Your sunscreen choice. For more info

4 Be aware and avoid to use a large amount of Chemicals

The chemicals you use on land, will eventually end up in the ocean. New studies prove, that chemicals originating from land, causes ocean animals dying, - including corals. So try to avoid using a large amount of chemicals.

5 Avoid buying coral souvenirs

When traveling, avoid buying coral souvenirs like jewelry, sculptures etc. and enjoy watching the living corals on the reef instead.

If You buy coral souvenirs You might be supporting harvesting the wild corals. Many corals are now grown for commercial use, - but it is still extremely common that the corals used for ornaments, jewelry etc. is from the wild… So to be sure not to support this harmful harvesting - simply avoid buying.

By Blue Reporter, Naja Bertolt Jensen


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