Earth’s oceans are home to some of the most diverse ecosystems on the planet, but warming temperatures are causing the disappearance of many marine animals, including corals. A new study on managing the effect of climate change on these organisms indicates that greater international collaboration is needed to secure the future of more than 6,000 coral species.
“Coral reefs are a critical ecosystem on our planet,” said Andrea Grottoli, study co-author and professor of earth sciences at Ohio State University. “Coral reefs are really important to humans as they protect coastlines from erosion and storms, and they’re essential for certain services like tourism and other parts of the economy.”
The study, published in the journal Biology of global changeadvocates the use of medium-scale sanctuaries, or areas that can extend for thousands of miles, often across national borders, to protect these ocean environments.
“Global warming is the No. 1 threat to coral reefs right now,” Grottoli said. “So when we think about coral reef conservation, we can’t limit ourselves to arbitrary geographic boundaries.”
Providing a “conservation continuum” would be hugely beneficial for the reefs, Grottoli said. But because conservation policies differ between different governments and politicians, this can make it difficult to protect the environment.
Although coral reefs occupy less than 0.1% of the surface of Earth’s oceans, about 30% of all marine species are associated with them in some way, Grottoli said. But due to the stress of rising sea temperatures, coral reefs around the world have experienced higher rates of coral bleaching, or the visible fading of coral surfaces.
Beneath the coral bleaching, the animal’s skeleton, once obscured, becomes visible and effectively turns the creature into a ghostly faded white. Although bleached coral is not immediately dead, it can lead to mass mortality. Researchers say mass bleaching events are an indicator of declining ecosystem health.
Many people may know coral best from the Great Barrier Reef, a complex coral system so vast that living structure can be spotted from space. Located just off the coast of Australia, over 2 million tourists visit the area each year. The attraction brings in an estimated annual economic value of around $36 billion.
Yet despite being the most protected marine area in the world, the GBR was recently hit by another massive bleaching event, the fourth time in just six years.
While climate change has undoubtedly contributed to the increased frequency and intensity of these events, warming seas are also altering the composition and architectural complexity of coral reefs. “In this reality, the future of coral reefs may look bleak,” the newspaper said.
But there is good news. Even as the world’s coral population declines, the genetic diversity of coral species helps ensure that some corals may be able to adapt and recover. And while there is an urgent need to reduce global greenhouse gas emissions, the study also suggests that in the meantime, we need to take broad, transdisciplinary approaches to creating local and large-scale ocean sanctuaries.
Grottoli thinks much of the heavy lifting to save the coral will come through education.
“People who understand coral reefs and understand the value of coral reefs are much more likely to do something to help protect them,” she said. “If you don’t know anything about coral and you’ve never seen one, how can you empathize or feel a connection to this ecosystem?”
In her role as president of the International Coral Reef Society, Grottoli and her colleagues have even put together a series of actions that individuals can take at home to help scientists’ conservation efforts.
This research was supported by the National Science Foundation.