News

June 7, 2020

Coral Reefs Are Facing Their Own Pandemic — But We Have A Survival Guide

News Source: CNN

Author(s): Jack Kittinger

Coral reefs are facing their own pandemic. For years, people have compromised the immunity of these ecosystems through pollution and overfishing. Meanwhile, climate change has created a fever in our oceans by raising temperatures and acidifying seas. The resulting outbreak has decimated approximately half of the world's reefs.

This devastation is well known. When I tell people that I work on coral reefs, their instinct is to offer condolences. What is less well known, and arguably more important, is that it's not too late to save our remaining reefs. We can -- and must -- take action to save these vital ecosystems.

By some estimates, coral reefs provide food and livelihoods for a billion people around the world. They also support one out of every four marine species. But their value isn't just economical or biological. Reefs are the undersea wonders of the world -- vibrant, kaleidoscopic places that have inspired the art, science and cultures of people for millennia. To lose these treasures is to diminish ourselves.

Survival strategies

Those of us working to save reefs have a few different strategies we can implement. The two most fundamental ones involve putting in place strong fishing regulations or creating a marine protected area. These approaches come in many different forms -- we have a lot of tools in the toolbox we can apply.

Think of these strategies collectively as a coral reef first-aid kit. There are a range of potential cures inside, but the effectiveness of each depends on the particular injury suffered.

Over the past decade, I've worked with a team of global researchers to study these remedies and their effectiveness at treating various maladies. Together, we analyzed management strategies in 1,800 coral reefs across the Indian, Pacific and Atlantic oceans to understand why some strategies work and others do not.

We found that the effectiveness of a strategy depends on the initial health of the reef and the level of human pressure it experiences. How much an individual reef has been degraded and how much stress it is exposed to inevitably shapes our ability to restore that ecosystem.

Conservation potential

Unfortunately, for highly degraded reefs where there is a lot of human pressure, our options are limited. About half of the world's reefs fall into this category. A lot of reefs surrounding the island I live on, O'ahu, Hawaii, are in this highly degraded state, owing in part to the million people that live on this island. Conservation gains in these places are going to be hard to achieve, even if we use everything in the first-aid kit.

The picture is very different on the other side of the spectrum. The least degraded reefs, which represent only about 10% of the global population, have it all: diverse fish populations, and functioning ecosystems. These include places like Indonesia's Raja Ampat. Our strategy for these areas should be simple: keep them intact and highly protected. By minimizing threats like pollution and overfishing, we can help these reefs stay as healthy as possible in the face of climate change.

Where things really get interesting is in the places where human pressure is relatively limited --the less stress a reef is under, the greater the conservation potential. Reefs in this category exist in all the oceans -- they aren't in just one country, or one region. Some of these reefs are fairly degraded. Others are fairly healthy. But they all have the potential for significant conservation gains.

By establishing marine protected areas and more effectively regulating fishing practices, we can dramatically improve the outcomes for these reefs, and ensure that they have a fighting chance to withstand the climate crisis.

Clearly, these are the areas where we must focus our efforts. If we do nothing, these reefs may eventually become highly degraded and beyond our ability to help. But if we invest intensively now, we can help these areas join their healthiest and most vibrant peers.

Nancy Knowlton, a prominent marine scientist at the Smithsonian Institution, has championed the idea that we need to move "beyond writing the obituaries" for coral reefs. So, my co-authors and I set out to understand the science of reef survival.

What has emerged from our research is a survival guide, one that can explain what works -- where and why. If we want to overcome the pandemic destroying our reefs, we must put this plan into action.