The importance of coral
Corals are arguably one of the coolest creations of nature. They are often referred to as the “rainforests of the sea” due to their high levels of biodiversity. Although corals only represent 1% of the world’s oceans, they support 25% of all marine species. Coral reefs host a wide range of marine life, including fish, crustaceans, molluscs, and various other species. They form an integral component of our planets life support systems. As such, humans have for a long time relied on this abundance of aquatic resources and fishing is one of the oldest forms of subsistence. In the wider marine industry, corals are extremely valuable, contributing an estimated $10 trillion a year to the global economy.
Corals are in fact living animals (polyps), not plants as commonly thought. When corals grow over time, they form reef like structures. These reefs are called ‘barriers’ when they run parallel to the coastline and protect the shallow waters and the species that live there from the open sea. This barrier can also act as natural protection against hazards.
Since they grow very slowly, at an average rate of just 2cm per year, some of the corals we see today have taken as long as 25 million years to form. This is why scientists are so concerned when corals die – once they’re gone, their populations won’t be restored within a human lifetime!
A quick bit of science, how are coral reefs made?
Corals are most commonly found in warm, shallow waters. Reefs thrive in clear, tropical and subtropical waters. They require sunlight for algae (called zooxanthellae), to grow and provide energy for the coral polyps. It’s these polyps that are the reef builders. They are tiny, soft-bodied organisms that live within a skeleton they create. These are the structures that can be seen when looking at coral. As the polyps multiply and die, their skeletons accumulate and form the structure of a coral reef over time. These reefs can create the largest living structures on the planet, easily visible from space. How cool is that! And it gets better… Unbelievably corals were around at the time of the dinosaurs – this makes them over 500 million years old! What’s not to love about that?
Threat to coral reefs
The prominent cause of coral decline relates to climate change. A warming planet translates to a warming ocean. In some cases a water temperature change of only 2 degrees can cause coral to become seriously stressed. But coral reefs are facing numerous threats, including, ocean acidification, pollution, overfishing, and other destructive fishing practices. Did you know one of the most damaging reef fishing practices involves dropping dynamite from vessels to stun fish, which then float to the surface and can be bagged up as easily as picking items from a supermarket shelf. Sadly, the coral reef also suffers long lasting destruction from the indiscriminate nature of this practice. Blasted reefs and crumbling corals have been seen in some of the worlds most prized reefs even today. Efforts are underway to deter the practice.However, a UN environmental report published in 2020 predicts that coral reefs as we know them are unlikely to survive beyond 2100.
We’ve heard of coral bleaching, but what is it?
Coral bleaching is a significant threat to the health and survival of coral reefs around the world. It occurs when coral colonies expel the algae living within their tissues, leading to the loss of vibrant colours and a whitening or bleaching appearance. Coral bleaching itself is not always fatal to the coral. But it is often an indicator of stress and can have severe consequences for both the coral reefs and the ecosystems they support.
Coral bleaching is primarily driven by elevated sea temperatures, which are linked to climate change. As climate change progresses, rising sea temperatures become more frequent and severe, increasing the frequency and intensity of coral bleaching events. This creates a dangerous feedback loop where coral bleaching contributes to the decline of coral reefs, which, in turn, reduces the reef’s ability to withstand further stressors and adapt to changing conditions. But we can help; by reducing as many stresses on coral as possible, we give them the best chance to survive the threats they already face.
Solutions to protect our corals
There are numerous ways humans are playing reef doctor and helping to give corals the best chance for survival. From identifying and reducing dominant invasive species, to finding and growing more resilient strains of coral. There are also strategies to engage and educate local communities of the risks to help minimise physical damage and promote restoration.
The key here is a multi-pronged approach. Corals have evolved in such diverse environments and are exposed to a range of threats. They require and deserve a truly superhuman effort to promote their survival and this is where you can help…
Protect corals from your home. As climate change is the number 1 cause of damage to corals, by minimising your carbon footprint and encouraging others to do the same, you are helping corals.
Join the Marine Conservation Society – Become a member | Marine Conservation Society (mcsuk.org)
When visiting a coral reef, practise safe and responsible diving and snorkelling, don’t touch the reef, walk or anchor over the reef.
Choose a coral reef friendly suncream. Some sunscreen ingredients can damage corals – Best eco-friendly sunscreen 2023 | The Independent
Get involved in a citizen science programme – Citizen scientists dive into ocean conservation (unep.org)