The Importance of Coral Reefs and How To Keep Them Healthy

Written by Demi Herveille

Posted on 07/10/2022

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As kids we used to be hyped watching movies such as Finding Nemo and be amazed by the wonders of the sea whilst visiting a public aquarium with our parents. Now, as adults, we dream away to the soothing voice of David Attenborough in a nature documentary as he takes us on an adventure through the beautiful and colorful coral reefs.

Unfortunately, the previous is only partly in line with the harsh reality we find ourselves in today. Rising CO2 levels in the atmosphere and the global warming that comes with that, has a major effect in the ocean as well. Our precious coral reefs are now threatened by the risk of mass extinction due to, amongst other reasons, ocean heatwaves, deoxygenation and acidification of the seas.[1] Note deserves that the decline of coral reefs can also be caused by more local threats, such as over-fishing, pollution and coastal development.[2]

Earlier this year, the World Meteorological Organization (WMO) stated in an update that the annual mean global near-surface temperature for each year between 2022 and 2026 is predicted to be between 1.1 – 1.7 degrees higher than pre-industrial levels.[3] While coral reefs already have a risk of decline of 70-90% with 1.5 degrees of warming, by the time we reach 2 degrees of warming – which is the intended maximum of allowed warming according to The Paris Agreement- the prediction is that 99% of the coral reefs will have been killed.[4] Giving these figures, one could plead that we should not let global warming escalate to 2 degrees and beyond. One might also wonder why it is important to protect coral reefs at all.

Let me start by explaining what coral reefs even are. A coral is an animal not a plant! that is made out of small, identical polyps of a few millimeters that form colonies. The corals are formed by a type of calcium carbonate called aragonite. Corals often live in a symbiosis with zooxanthellae, which are basically small, unicellular algae that help with growth by feeding the coral through photosynthesis and also give the coral its unique color. If the water temperature gets too high a coral will get ‘sick’, and eventually die. The coral will expel the previously mentioned algae, which will cause the coral to lose its color, also known as the ‘bleaching-effect’. Eventually, if the coral does not recover and the water temperature does not drop anytime soon, the coral will die due to lack of nutrients. All of that coral dying is a sad fact, because a healthy coral reef can house a lot of biodiversity.[5] Coral reefs are sometimes referred to as the ‘tropical rainforest of the sea’, since the ecosystem is believed by many to be one of the most biodiverse on the planet. Even though coral reefs only occupy less than 1% of the ocean floor, healthy ones are believed to support more that 25% of all marine life.[6]

The question arises as to why the protection of coral reefs is also in the interest of us – humans. Coral reefs are valuable to us because an estimated 1 billion people benefit either directly or indirectly from the ecosystem services coral reefs provide. These services include, amongst others, job generation, food sources and livelihood (because the structure of a coral reef provides important coastal protection from wave energy). The reefs also provide an important source for the development of new medicine to treat, amongst others diseases, cancer, Alzheimer’s disease and heart disease. It is also worth mentioning that coral reefs provide a certain cultural value, attract (eco-)tourism and thus stimulate the economy as well.[7] The estimated total economic value of coral reefs in the U.S. is 3.4 billion dollars annually.[8] Also, local communities near reef ecosystems receive billions of dollars from reef visitors through, for example, dive and snorkel related activities, recreational fishing, hotels and restaurants.[9]

As environmental writer Mark Lynas puts it perfectly in his book Our Final Warning, it would be strange not to suffer from ‘ecological grief’ if you think about billions of coral eggs being uselessly dispersed in the warming ocean. It is not only the coral reefs that are being destroyed, but also the future of the next generations of people, who, thanks to the polluting past and current generations, may not see with their own eyes the spectacular underwater world we once admired.[10]

It should be clear by now: the ocean desperately needs our help. I would like to conclude this contribution with some suggestions on how you too can take small and larger action to contribute to the conservation and restoration of coral reefs:

Ideas for small action:

  • Calculate your ecological footprint on and try to adjust your behavior on the results as much as you can.

  • Take the bike more often, carpool with friends and colleagues to work or school or make good use of travel by public transport to reduce your CO2 impact during traffic.

  • Be conscious, economical and sustainable with your energy consumption -and choices- at home. For instance, let your laundry air-dry a bit more often, use energy-efficient lamps, turn the lights off when you don’t need them, try to repair instead of immediately replace, lower the heating during winters (however, this mustn’t be too difficult with the current gas prices), etc.

  • Be careful with what you flush down the drain. Examples: Never throw old frying fat down the drain, leave hygiene products in the designated trash can, go for eco-friendly and certified soaps and shampoos that are either organic or provided with an ecolabel and also prevent scrubs and shampoos that contain polyethylene (and thus microplastics).

  • Try to avoid the single use of plastic. Nearly 700 marine species are known to be affected by plastic debris in the ocean. A good start would be purchase a reusable water bottle and/or coffee mug. Another idea would be to replace plastic straws with glass, metal or ‘pasta’-straws. And also: whenever your hands are free and you find a piece of plastic roving around: pick it up and throw it in the (designated) bin.

  • Be conscious about the sunscreen protection you wear and, when purchasing, make sure it doesn’t contain oxybenzone or benzophenone, because these chemicals can harm corals and other marine life.

  • And now for the fun part: Discover the ocean and educate yourself! As marine biologist Mariasole Bianco wrote in her book: ‘Man protects what is dear to him and loves what he knows’. Read books about the ocean, climate change and sustainability, go for a (guided) discovery scuba dive or snorkeling trip if you have the opportunity, watch nature documentaries, listen to podcasts, go for a walk on the beach, the list goes on.[11]

Ideas for larger action:

  • You could make a donation to a coral reef protecting agency of your choice. Some agencies might also offer an Air Miles-donation option.

  • You could create a fundraiser for a coral reef restoration project on social media platforms such as Facebook or Instagram.

  • You could adopt a coral, which then a ‘coral gardener’ will plant for you. This is a unique way of helping to rebuild coral reefs.

  • If you are a certified diver you could participate in a reef renewal project as a volunteer, where you will learn how to outplant corals and how to maintain them. As a diver you can also offer your help and skills during anti-debris dives.


[1] Lynas, M. (2020). Our Final Warning. Six degrees of climate emergency (1st edition). 4th – London, p. 57-60.

[2] ‘Coral reefs. Status and outlook of coral reefs around the world’.

[3] ‘WMO update: 50:50 chance of global temperature temporarily reaching 1.5 degrees threshold in next five years’.

[5] Bianco, M. (2020). Onder het oppervlak. Duik mee naar de bodem van de oceaan (1st edition). Noblesse Uitgevers – Nieuw Vennep, p. 115-118, 127-128.

[7] ‘Coral reefs. Status and outlook of coral reefs around the world’.; ‘Medicines from the sea’.

[8] Brander, M. & Van Beukering, P. ‘The total economic value of U.S. coral reefs. A review of the literature”.

[9] ‘How do coral reefs benefit the economy?’

[10] Lynas, M. (2020). Our Final Warning. Six degrees of climate emergency (1st edition). 4th – London, p. 63.

[11] Bianco, M. (2020). Onder het oppervlak. Duik mee naar de bodem van de oceaan (1st edition). Noblesse Uitgevers – Nieuw Vennep, p. 199-205; Egger, M. (2021). ‘Neuston in the great pacific garbage patch and the impact of cleanup’.

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