World Oceans Day 2020

Coral Reef Wilderness, Not Just a Luxury

By T. R. McClanahan | June 8, 2020

Image for post
Image for post
The Nassau grouper forms dense spawning aggregations that face extirpation where fisheries regulations do not actively protect them. The Wildlife Conservation Society is helping to protect these aggregations with the help of the Belize Fisheries Department at the Glovers Reef Atoll. Credit: T. R. McClanahan/WCS.

recent study of the Earth’s last coral reef wilderness strongholds suggests a crisis is brewing for tropical fisheries. It’s a crisis driven on the one hand by the need for conservation of nearshore areas closed to fishing that allow fish populations to thrive and make sustainability possible; and, on the other, by a decline of remote wilderness that until recently has been preventing the worst fisheries disasters.

The report, by the Wildlife Conservation Society (WCS) and partners, suggests that active management and conservation of captured fish species that require less space and grow faster should be moved and located closer to shore. At the same time, areas further from shore can be managed by fishing policies that restrict access and focus on vulnerable species with large area needs or via “passive” conservation.

Given the current consensus that 30 percent of fisheries ecosystems in a given region need to be conserved to experience their full benefits, how should these two forms of conservation be partitioned? A failure to plan will cause the decline of refuges for fish, which will cause losses of biodiversity and ecological connectivity, the inability of fish to recover from collapses, adverse changes to the evolutionary processes of fish, and lost fisheries productivity and food security benefits to people.

Image for post
Image for post
The lobed brain coral makes fluorescent proteins that reflect light to prevent overheating, a possible useful adaptation to climate warming. Credit: T. R. McClanahan/WCS.

Whereas we once believed that that active protection of corals covered around 12 percent of the world’s reefs, these new findings suggest that this was a considerable overestimate. The new estimate, based on random sampling of a recent reef map, suggests that a mere 2.5 percent of all reefs are actively conserved.

This overestimate is probably due to a combination of factors that include: relying on non-reef (but associated) habitats, limiting estimates to nearshore environments, and incomplete coverage in the past. The result is a less optimistic view of the status of reef protection and a new call for thoughtful action.

And yet a potentially more optimistic view of reef conservation emerges from the new findings if we estimate passive conservation — that is, if we quantify the number of reefs that are distant from people and cities. By this measure, 14 percent of reefs were more than four hours, and 48 percent more than 9 hours from human settlements and large markets, which enables maximum replenishment of fish stocks.

The fish stock estimate is based on an examination of 3,684 studies of coral reefs and their distance from people and cities.

“A new set of global food security priorities arise from knowing where to focus active marine conservation. When combined with economic policies that promote passive conservation, the likelihood of future collapse of fisheries is reduced.”

The implication is that most conservation of reefs is passive, conserved simply because of the high cost of travel to these remote reefs. Yet, this is not how the status of reefs has been evaluated historically. One advantage of passive conservation is that it can be affordably protected by enacting policies that influence travel costs and access, such as eliminating travel subsidies or instigating taxes that increase travel costs to remote reefs.

Image for post
Image for post
The Orbicular batfish has a natural range that spans from the Indian Ocean to New Caledonia but has been observed in Florida — probably escaping from the aquarium trade. Credit: T.R. McClanahan/WCS.

All of this comes at time when many global initiatives, including the Blue Economy, Aichi, Millennium, and Sustainable Development Goals are pushing to increase the coverage of marine ecosystems protection. To achieve these goals and do better conservation, we must legally delineate, recognize, quantify, and monitor passive conservation areas and ecosystems. This would increase the conservation area estimates considerably at a low cost.

This seems logical, but it could run into conflict with some calls to increase access to fishers, many of whom are poor and struggle to make profits. A solution is to use existing fisheries subsidies to promote alternative livelihoods, economic diversification, and protection of stocks to ensure high yields are sustained.

Among the key nuances of the study were the large differences in passive conservation and national dependency on fish throughout the 99 ecological regions studied. These metrics made it clear that most of the Africa, Asia, and the Caribbean coasts are poised for fisheries disasters driven by a combination of lack of refuge and high dependency on fish.

Image for post
Image for post
The big-eye jack lives near coral reefs in large schools from the Red Sea to Baja California. It can grow up to 1.2 meters. Credit: T. R. McClanahan/WCS.

Using the 30 percent refuge criteria, overall, 15 of the regions had no refuge and 35 had less than the recommended threshold for fisheries stability. Thus, a new set of global food security priorities arise from knowing where to focus active marine conservation. When combined with economic policies that promote passive conservation, the likelihood of future collapse of fisheries is reduced.

Our study shows that a large amount of reef wilderness that remains off-limits to fishing and human presence is under the legal jurisdiction of wealthy temperate nations with low dependency on fish. Marine wilderness cannot be just a luxury of wealthy countries. Fortunately, these countries — which include the UK, USA, France, Australia, China, Brazil, and New Zealand — are poised to lead the effort to support and maintain wilderness..

Success must be measured by the degree to which these countries maintain Indigenous People’s human and property rights. This legal environment provides a testing ground for finding a balance and supporting a move towards blended governance that acknowledges the local and global priority of supporting marine wilderness.

“Local nearshore closures are a key part of actions needed for fisheries sustainability and must be integrated into the most heavily fished seascapes to deliver the food security critical to the poorest nations.”

The study found that the majority of active protection coverage is more than 4 hours travel times from human settlements — or beyond easy access by small-scale fishers. This distribution may occur because many legally establish protected area territories were developed to avoid conflict with nearshore economic interests, such as fishing and non-renewable resource extraction.

In other words, legally protected areas are frequently too far from people to be very useful for local fisheries management. Yet, local nearshore closures are a key part of actions needed for fisheries sustainability and must engage and resolve potential conflicts to achieve their goals. They must be integrated into the most heavily fished seascapes to deliver the food security critical to the poorest nations.

Image for post
Image for post
The blue nudibranch (Hypselodorisi), seen here mating in Malaysia, is a member of a diverse genus with 48 species, 17 of which were only discovered in the past two years. Credit: T. R. McClanahan/WCS.

One problem with asking all countries to protect 20–30 percent of their marine environment is that this process of conflict avoidance may continue. If so, countries will not protect what is important for sustainability — nearshore habitats and fish stocks.

The value of this study is that it uncovers and proposes that travel times to reefs are a good way to evaluate the state of reefs. It also asks that this metric become part of the governance systems that acknowledge current fisheries science and the goals of sustainability. This is a case where better science can help to avoid a looming crises for both rich and — particularly — poor countries.

T. R. McClanahan is a Senior Conservationist with WCS (Wildlife Conservation Society).

Our Ocean, Our Future

Conserving and managing the marine biodiversity of our…

Wildlife Conservation Society

Written by

WCS saves wildlife and wild places worldwide through science, conservation action, education, and inspiring people to value nature.

Our Ocean, Our Future

Conserving and managing the marine biodiversity of our oceans is a monumental task that few countries have the capacity to do on their own. WCS is responding by investing in ocean protection, sustainable fisheries, and marine species conservation where the need is greatest

Wildlife Conservation Society

Written by

WCS saves wildlife and wild places worldwide through science, conservation action, education, and inspiring people to value nature.

Our Ocean, Our Future

Conserving and managing the marine biodiversity of our oceans is a monumental task that few countries have the capacity to do on their own. WCS is responding by investing in ocean protection, sustainable fisheries, and marine species conservation where the need is greatest

Medium is an open platform where 170 million readers come to find insightful and dynamic thinking. Here, expert and undiscovered voices alike dive into the heart of any topic and bring new ideas to the surface. Learn more

Follow the writers, publications, and topics that matter to you, and you’ll see them on your homepage and in your inbox. Explore

If you have a story to tell, knowledge to share, or a perspective to offer — welcome home. It’s easy and free to post your thinking on any topic. Write on Medium

Get the Medium app

A button that says 'Download on the App Store', and if clicked it will lead you to the iOS App store
A button that says 'Get it on, Google Play', and if clicked it will lead you to the Google Play store