Corals

Corals, essential to our ocean’s health, are in danger.

Understand why

Corals are essential

A habitat for biodiversity

A habitat for biodiversity

Corals represent an exceptional biodiversity, and are present in both tropical and cold waters. Scientists estimate that coral reefs are home to more than 25% of marine species and yet they cover less than 0.2% of the ocean. Corals are also at the core of the formation of other ecosystems.

A coastal protection

A coastal protection

Reefs only cover 0.2% of the oceans. Yet they protect more than 150,000 kilometres of coastline in more than 100 countries and territories. They can form a barrier that absorbs wave energy and thus help reduce coastal erosion.

A food resource

A food resource

Approximately 1 billion people live within 100 kilometres of coral reefs and are likely to benefit from their ecosystem services. 330 million people directly depend on them. Reefs can yield between 5 and 15 tonnes of fish and shellfish per square kilometre.

A wealth for tourism

A wealth for tourism

Reefs are often an essential part in the economy of the tropical regions where they are located. Indeed, they attract divers, snorkelers, recreational fishermen and beach and white sand enthusiasts.

Of economic importance

Of economic importance

Millions of people around the world depend on reefs for employment. According to an estimate, the total annual net benefit of the world’s coral reefs is $29.8 billion.

A medical future

A medical future

Corals also contribute to research advancements, in particular by providing interesting possibilities for the treatment of various diseases.

A habitat for biodiversity A coastal protection A food resource A wealth for tourism Of economic importance A medical future
Reef - Coral Guardian

A habitat for biodiversity

Corals represent an exceptional biodiversity, and are present in both tropical and cold waters. Scientists estimate that coral reefs are home to more than 25% of marine species and yet they cover less than 0.2% of the ocean. Corals are also at the core of the formation of other ecosystems.

fishing village

A coastal protection

Reefs only cover 0.2% of the oceans. Yet they protect more than 150,000 kilometres of coastline in more than 100 countries and territories. They can form a barrier that absorbs wave energy and thus help reduce coastal erosion.

fishing - Coral Guardian

A food resource

Approximately 1 billion people live within 100 kilometres of coral reefs and are likely to benefit from their ecosystem services. 330 million people directly depend on them. Reefs can yield between 5 and 15 tonnes of fish and shellfish per square kilometre.

marine protected area - Coral Guardian

A wealth for tourism

Reefs are often an essential part in the economy of the tropical regions where they are located. Indeed, they attract divers, snorkelers, recreational fishermen and beach and white sand enthusiasts.

Fishing - Coral Guardian

Of economic importance

Millions of people around the world depend on reefs for employment. According to an estimate, the total annual net benefit of the world’s coral reefs is $29.8 billion.

scientific monitoring - Coral Guardian

A medical future

Corals also contribute to research advancements, in particular by providing interesting possibilities for the treatment of various diseases.

An endangered ecosystem

Over the past 240 million years, corals have evolved into one of the most important and complex ecosystems on the planet. However, climate change and local risks threaten to wipe corals out entirely. If we do not act quickly, according to some scientists, corals could disappear by 2050.

2°C

temperature increase is the limit not to be exceeded, or else all the world’s corals will be doomed.

40 %

of coral reefs and mangroves have disappeared in the last 40 years.

Global risks

Water temperature increase

Corals are very sensitive to temperature changes. 1 to 2°C increase in surface water temperature above the usual maxima is enough to cause massive bleaching, affecting reef growth, feeding, and other ecological processes. The IPCC’s forecasts anticipate a global temperature increase of 1.5°C by 2050. This means that ocean surface water will continue to warm.

Ocean acidification

Global climate regulation is achieved through the absorption by the oceans of 33% of the CO2 emitted. However, human activities are generating an exponential increase in these emissions, raising the dissolution of CO2 and causing ocean acidification. This has a huge impact on the proper development of organisms with calcareous skeletons.

Water temperature increase Ocean acidification

Corals are very sensitive to temperature changes. 1 to 2°C increase in surface water temperature above the usual maxima is enough to cause massive bleaching, affecting reef growth, feeding, and other ecological processes. The IPCC’s forecasts anticipate a global temperature increase of 1.5°C by 2050. This means that ocean surface water will continue to warm.

Global climate regulation is achieved through the absorption by the oceans of 33% of the CO2 emitted. However, human activities are generating an exponential increase in these emissions, raising the dissolution of CO2 and causing ocean acidification. This has a huge impact on the proper development of organisms with calcareous skeletons.

Local risks

Pollution

Wastes such as oil, fertilizers, sewage and toxic chemicals can be released directly at sea or indirectly (via rivers). This causes an enrichment of nutrients that promote the formation of algae. The supports used by coral larvae are smothered by a proliferation of algae thus affecting their development.

Destructive fishing

In certain countries, the use of homemade bombs for fishing is disastrous. It leads to the destruction of reefs leaving only unstable rubble remains in their wake, making recolonisation by coral larvae impossible. It is also a social problem: fishermen have to go further afield (at a higher cost to them) and take more risks in order to find fish. Potassium cyanide also destroys all life on reefs and is used to harvest species for the aquarium and food markets in Asian countries.

Overfishing

The increase in the demand for fish has resulted in the overfishing of reef fish which in turn affects the balance of the coral ecosystem. For example, overfishing of herbivorous fish can lead to levels of growth in algae, which asphyxiates the coral by depleting it of oxygen.

Tourism

More than 100 countries benefit from reef-related tourism and it contributes to more than 30% of export earnings in more than 20 countries. Moreover, reef tourism is on the rise. Indeed, reefs attract divers, snorkelers, recreational fishermen and white sandy beach-lovers. Thus, they are an essential part of the economy for the regions where they are located. In many small islands, more than 90% of new economic development depends on this coastal tourism.

Pollution Destructive fishing Overfishing Tourism

Wastes such as oil, fertilizers, sewage and toxic chemicals can be released directly at sea or indirectly (via rivers). This causes an enrichment of nutrients that promote the formation of algae. The supports used by coral larvae are smothered by a proliferation of algae thus affecting their development.

In certain countries, the use of homemade bombs for fishing is disastrous. It leads to the destruction of reefs leaving only unstable rubble remains in their wake, making recolonisation by coral larvae impossible. It is also a social problem: fishermen have to go further afield (at a higher cost to them) and take more risks in order to find fish. Potassium cyanide also destroys all life on reefs and is used to harvest species for the aquarium and food markets in Asian countries.

The increase in the demand for fish has resulted in the overfishing of reef fish which in turn affects the balance of the coral ecosystem. For example, overfishing of herbivorous fish can lead to levels of growth in algae, which asphyxiates the coral by depleting it of oxygen.

More than 100 countries benefit from reef-related tourism and it contributes to more than 30% of export earnings in more than 20 countries. Moreover, reef tourism is on the rise. Indeed, reefs attract divers, snorkelers, recreational fishermen and white sandy beach-lovers. Thus, they are an essential part of the economy for the regions where they are located. In many small islands, more than 90% of new economic development depends on this coastal tourism.

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