1. Why Are Coral Reefs Dying?
Coral reefs around the world are dying primarily due to the impact of humans on the environment. Rising sea temperatures are a result of climate change driven by the burning of fossil fuels. This is the main reason for coral bleaching, which is causing reefs to die. Additionally, pollution, ocean acidification, overfishing, destructive fishing methods, and dredging are all threats to coral reefs. This damage has made reefs less resilient against disease and the natural threats they face, such as the El Niño weather pattern and the Crown of Thorns Starfish.
2. What Is Coral Bleaching?
Caused mainly by rising sea temperatures, coral bleaching occurs when corals expel their zooxanthellae algae. These algae live within the corals and are the reason for the well-known vibrant colors of corals. Coral polyps lose the zooxanthellae due to stress caused by variations in water temperatures and pollution. As the corals depend on the algae for food, they are starved and more vulnerable to disease when bleaching occurs. They also lose their color and appear white, hence the term bleaching. If the coral does not recover from bleaching, it dies and turns brown.
Coral reefs require time to recover from bleaching events, but there has been an increase in these events’ frequency and severity over the years. For example, this year saw the third mass bleaching event of Australia’s Great Barrier Reef in five years. The consecutive nature of these occurrences does not give the coral sufficient time to recover.
3. What Is The State Of The Great Barrier Reef?
The Great Barrier Reef has lost more than half its corals since 1995, with unusually large damage caused by mass bleaching events in 2016, 2017, and this year. While there has been a considerable amount of damage done to the reef, it is not yet a completely dead reef. It is under threat and requires assistance if it is to survive, but much of it thrives despite widespread bleaching. Coral can regenerate, but reefs grow very slowly, so work is being done to assist the rebuilding. This video shows some footage of the Great Barrier Reef bleaching before and after work by scientists to restore parts of the reef following bleaching events and cyclones.
4. Why Are Coral Reefs Important?
Coral reefs provide food, shelter, and breeding grounds for many other ocean species and are an essential ecosystem. Often referred to as “the rainforests of the sea,” they support a massive amount of biodiversity and are vital to the health of the ocean and the planet itself. By helping to remove carbon dioxide from the atmosphere and producing oxygen through photosynthesis, there importance cannot be overstated.
They also benefit humans as they are natural coastal defense barriers against storms, tsunamis, and erosion. Additionally, they provide food, fishing, and tourism jobs and are an essential part of the economy. They also provide us with medical and pharmaceutical resources as extracts from coral reefs and the species that inhabit them have been used to develop treatments for various diseases.
5. How Can We Protect Our Coral Reefs?
As individuals, we can reduce our carbon footprint and contribute to the slowing of climate change by reducing our use of fossil fuels. We also need to be aware of what we consume and how we dispose of it to reduce mainly plastic pollution of the ocean. Joining or supporting marine conservation groups, lobbying for change on national and global levels, participating in beach and ocean clean-ups, and spreading the word about the threat faced by, and the importance of coral reefs, will all help to protect them.
Scientists are working to restore the damage done to reefs, but without global action on climate change, sea temperatures will continue to rise and cause further damage to reefs that are already struggling to survive. We all need to understand the benefits coral reefs bring to the world, their importance, and the need to save them from extinction.