Coral reefs are not only incredibly beautiful and colourful, they also inspire people worldwide – at least since the film ‘Finding Nemo’. Apart from this, corals fulfil other important tasks for our planet that few people are aware of.

Providing a habitat for fish, as a spawning or schooling ground, reefs feed entire families! A dead reef harbours no fish. It is just barren land without life. Coastal communities live from fishing. Provided fishing practices are controlled, fishermen in rural areas are dependent on coral reefs. Without corals – no fish.

Coral reefs are coastal protection! The structure of coral reefs acts as a natural breakwater. They reduce the energy of waves and thus protect the coasts from erosion and flooding. Especially in times of climate change and rising sea levels, intact reefs are of great importance.

Coral reefs provide millions of jobs for the local population through tourism, fishing and leisure activities.

They are the earth’s ‘medicine cabinet’. Many medicines are derived from coral reefs and this spectrum is far from exhausted. Much is still undiscovered. However, discovery depends on the survival of coral reefs.

Furthermore, marine ecosystems are the largest carbon sink in the world. Marine life is an essential part of the marine carbon cycle, which is essential for carbon storage. It is estimated that fish account for 16 per cent of the total carbon flux. But without corals – no fish.

Coral reefs are anything but healthy. Our planet has already lost about half of its shallow-water corals in the last three decades. If coral mortality continues at this rate, up to 90 per cent of all corals will have disappeared in less than 30 years. And that would be far more dramatic for the world than just a few fewer coral videos on social media.

Climate change and acidification:

Due to the rise in water temperatures worldwide, corals are losing the algae with which they live in symbiosis and are bleaching. This alone has caused global coral populations to decline by around 20 per cent in the last two decades. The second major problem is that the oceans are becoming more acidic, as they absorb around 30 per cent of the world’s CO2. The gas reacts to form carbonic acid and the pH value of the water drops – a danger for organisms that build their shells and skeletons from calcium carbonate: Corals become fragile and break off more quickly with the increase in extreme weather.

Destructive fishing:

Fisheries are increasingly using nets that roll across the seabed like bulldozers with their rollers and plates. Intact coral reefs that have grown over centuries can be destroyed in a very short space of time – turning into wasteland without life.
Dynamite fishing – long since banned in large parts of Indonesia – destroys brightly coloured reefs in underwater deserts in a fraction of a second. Anchor damage caused by negligent fishermen leaves healthy reefs as cratered landscapes. As a result, the habitat for animals is becoming increasingly scarce.

Pollution of the oceans:

Pesticides, herbicides, fertilisers, detergents, sewage, oil and vast amounts of plastic particles and other solids are turning our oceans into a landfill. Around 675 tonnes of waste end up in the sea every hour, half of which is plastic and the resulting microplastics. The majority of this waste (80 per cent) comes from land and ends up in the sea via rivers. But maritime traffic also contributes to this. This pollution not only damages the health of all organisms in the ocean, but also increases the growth of algae, which clouds the water and deprives corals of the sunlight they need.

Recreational activities:

Our behaviour in the ocean during activities such as snorkelling or simply swimming in the sea after sunbathing damages corals immensely. A component of many sunscreens turns into a light-activated toxin in coral polyps. This phototoxin is particularly harmful to corals that are already affected by bleaching.

Divers with inadequate buoyancy control destroy corals or stir up the substrate so that sand suffocates the sensitive coral polyps.

Corals are actually tiny animals and not plants. They feed on plankton and excrete substances that form the basis of coral reefs. They cling together in colonies for their entire lives and filter nutrients from the ocean. The best known corals are stony corals, as they can form large reefs on which they live. In the course of their lives, stony corals excrete calcium carbonate, so that the mountain on which they are attached becomes larger and larger. When a coral dies, the calcium carbonate remains and is immediately colonised by new corals. Because coral reefs grow very slowly, scientists assume that the world’s large reefs are many thousands of years old.

Corals belong to the polyp family (cnidarians). Their body structure is very simple: a hollow, soft, skeletonless cylinder with a mouth opening at the top, which is surrounded by tentacles. The polyp uses the tentacles to hunt plankton and defend itself. Many corals also live in symbiosis with small algae. The algae use photosynthesis to produce carbohydrates, which the polyps feed on.

Coral reefs are home to a wide variety of marine life. Fish, snails, crabs and mussels live here or come to the reef to hunt. Coral reefs are therefore also the nursery of countless fish species. Just like at our Livingseas Coral Restoration Site. A few months ago, the first baby sharks even moved in and large schools of barracudas tunnel over the reef! Reefs are the infrastructure for life under water. If there are no reefs, there are no fish. It’s as simple as that.

Acropora corals are among the most important building blocks of a coral reef. Their filigree, branching structures grow particularly quickly and create habitats for numerous marine species within a short space of time. These pioneer corals are essential for the first phase of reef regeneration, as their rapid colonisation reduces algae growth and stabilises the ecosystem.

But a healthy reef needs more than just fast pioneers. Slow-growing hard coral species, such as Porites or Favia, form massive calcareous skeletons that provide long-term structural stability. These stable coral species protect the reef from erosion, withstand storms and create a permanent habitat for a variety of marine life. Their presence increases biodiversity and improves the natural reproductive cycles of the reef system.

Through this holistic approach, We Do OCEAN combines rapid regeneration with long-term resilience – for coral reefs that not only grow, but also endure.