The Kenyan marine ecologist David Obura is chair of a panel of the Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services (IPBES), the world’s leading natural scientists. For many decades, his speciality has been corals, but he has warned that the next generation may not see their glory because so many reefs are now “flickering out across the world”.
Why are corals important?
Multiple reasons. They are home to a huge amount of biodiversity, which provides food and environmental services. They also serve as coastal buffers, protecting coastlines from storms and swells. In many ways, coral are like underwater forests. The algae living inside corals are photosynthetic and grow very much like trees. Together, they are the ecosystem architects, and if you lose those, you lose the entire ecosystem.
What is happening to coral reefs?
There are sudden collapses and also long linear declines. It depends on the circumstances. Climate change and pollution are really changing the background environmental conditions that coral reefs need to survive in. And then through fishing and other exploitation, a lot of their biomass is being extracted. There are so many of these different pressures happening at the same time that it’s a death by a thousand cuts. In the end, you lose the interactions and the complexity that characterises a coral reef. Half of the total area of live coral has been lost already. Many reefs no longer support the diversity and abundance that they used to.
