Nav: Home

Fishing and pollution regulations don't help corals cope with climate change

February 19, 2019

A new study from the University of North Carolina at Chapel Hill reports that protecting coral reefs from fishing and pollution does not help coral populations cope with climate change. The study also concludes that ocean warming is the primary cause of the global decline of reef-building corals and that the only effective solution is to immediately and drastically reduce greenhouse gas emissions.

The new study published in the Annual Review of Marine Science (accessible via MarXiv: https://marxiv.org/ugk4v) found that coral reefs in areas with fishing and pollution regulations had the same level of decline as the coral reefs in unprotected areas, adding to the growing body of evidence that managed resilience efforts, like fishing and pollution regulations, don't work for coral reefs. This finding has important implications for how to protect reefs and best allocate scarce resources towards marine conservation.

Ocean warming is devastating reef-building corals around the world. About 75 percent of the living coral on the reefs of the Caribbean and south Florida has been killed off by warming seawater over the last 30 to 40 years. Australia's Great Barrier Reef was hit by extreme temperatures and mass bleaching in 2016 and 2017, wiping out roughly half of the remaining coral on the Great Barrier Reef's remote northern section.

Corals build up reefs over thousands of years via the slow accumulation of their skeletons and coral reef habitats are occupied by millions of other species, including grouper, sharks, and sea turtles. In addition to supporting tourism and fisheries, reefs protect coastal communities from storms by buffering the shoreline from waves. When corals die, these valuable services are lost.

The most common response to coral decline by policy makers and reef managers is to ban fishing based on the belief that fishing indirectly exacerbates ocean warming by enabling seaweeds that overgrow corals. The approach, referred to as managed resilience, assumes that threats to species and ecosystems are cumulative and that by minimizing as many threats as possible, we can make ecosystems resilient to climate change, disease outbreaks, and other threats that cannot be addressed locally.

The study's authors, led by John Bruno who is a marine ecologist in the College of Arts and Sciences at the University of North Carolina at Chapel Hill, performed a quantitative review of 18 case studies that field-tested the effectiveness of the managed resilience approach. None found that it was effective. Protecting reefs inside Marine Protected Areas from fishing and pollution did not reduce how much coral was killed by extreme temperatures or how quickly coral populations recovered from coral disease, bleaching, and large storms.

"Managed resilience is the approach to saving reefs favored by many scientists, nongovernmental organizations, and government agencies, so it's surprising that it doesn't work. Yet the science is clear: fishery restrictions, while beneficial to overharvested species, do not help reef-building corals cope with human-caused ocean warming," said Bruno.

The 18 individual studies measured the effectiveness of managed resilience by comparing the effects of large-scale disturbances, like mass bleaching events, major storms, and disease outbreaks, on coral cover inside Marine Protected Areas versus in unprotected reefs. Many also measured the rate of coral population recovery after storms. The decline in coral cover was measured directly, via scuba surveys of the reef, before and periodically after large-scale disturbances. Overall, the meta-analysis included data from 66 protected reefs and 89 unprotected reefs from 15 countries around the world.

The study also assessed evidence for various assumed causes of coral decline. For many, including overfishing, seaweeds, and pollution, evidence was minimal or uncertain. In contrast, the authors found that an overwhelming body of evidence indicates that ocean warming is the primary cause of the mass coral die-off that scientists have witnessed around the world.
-end-
Bruno collaborated with Dr. Isabelle Côté of Simon Fraser University and Dr. Lauren Toth of USGS St. Petersburg Coastal and Marine Science Center. Research was funded by the U.S. National Science Foundation, the Natural Sciences and Engineering Research Council of Canada, the U.S. Geological Survey's Coastal and Marine Geology program and the Climate and Land Use Research and Development program.

About the University of North Carolina at Chapel Hill

The University of North Carolina at Chapel Hill, the nation's first public university, is a global higher education leader known for innovative teaching, research and public service. A member of the prestigious Association of American Universities, Carolina regularly ranks as the best value for academic quality in U.S. public higher education. Now in its third century, the University offers 74 bachelor's, 104 master's, 65 doctorate and seven professional degree programs through 14 schools including the College of Arts & Sciences. Every day, faculty, staff and students shape their teaching, research and public service to meet North Carolina's most pressing needs in every region and all 100 counties. Carolina's nearly 330,000 alumni live in all 50 states, the District of Columbia, US Territories and 161 countries. Over 178,000 live in North Carolina.

University of North Carolina at Chapel Hill

Related Climate Change Articles:

The black forest and climate change
Silver and Douglas firs could replace Norway spruce in the long run due to their greater resistance to droughts.
For some US counties, climate change will be particularly costly
A highly granular assessment of the impacts of climate change on the US economy suggests that each 1°Celsius increase in temperature will cost 1.2 percent of the country's gross domestic product, on average.
Climate change label leads to climate science acceptance
A new Cornell University study finds that labels matter when it comes to acceptance of climate science.
Was that climate change?
A new four-step 'framework' aims to test the contribution of climate change to record-setting extreme weather events.
It's more than just climate change
Accurately modeling climate change and interactive human factors -- including inequality, consumption, and population -- is essential for the effective science-based policies and measures needed to benefit and sustain current and future generations.
Climate change scientists should think more about sex
Climate change can have a different impact on male and female fish, shellfish and other marine animals, with widespread implications for the future of marine life and the production of seafood.
Climate change prompts Alaska fish to change breeding behavior
A new University of Washington study finds that one of Alaska's most abundant freshwater fish species is altering its breeding patterns in response to climate change, which could impact the ecology of northern lakes that already acutely feel the effects of a changing climate.
Uncertainties related to climate engineering limit its use in curbing climate change
Climate engineering refers to the systematic, large-scale modification of the environment using various climate intervention techniques.
Public holds polarized views about climate change and trust in climate scientists
There are gaping divisions in Americans' views across every dimension of the climate debate, including causes and cures for climate change and trust in climate scientists and their research, according to a new Pew Research Center survey.
The psychology behind climate change denial
In a new thesis in psychology, Kirsti Jylhä at Uppsala University has studied the psychology behind climate change denial.

Related Climate Change Reading:

Best Science Podcasts 2019

We have hand picked the best science podcasts for 2019. Sit back and enjoy new science podcasts updated daily from your favorite science news services and scientists.
Now Playing: TED Radio Hour

Changing The World
What does it take to change the world for the better? This hour, TED speakers explore ideas on activism—what motivates it, why it matters, and how each of us can make a difference. Guests include civil rights activist Ruby Sales, labor leader and civil rights activist Dolores Huerta, author Jeremy Heimans, "craftivist" Sarah Corbett, and designer and futurist Angela Oguntala.
Now Playing: Science for the People

#521 The Curious Life of Krill
Krill may be one of the most abundant forms of life on our planet... but it turns out we don't know that much about them. For a create that underpins a massive ocean ecosystem and lives in our oceans in massive numbers, they're surprisingly difficult to study. We sit down and shine some light on these underappreciated crustaceans with Stephen Nicol, Adjunct Professor at the University of Tasmania, Scientific Advisor to the Association of Responsible Krill Harvesting Companies, and author of the book "The Curious Life of Krill: A Conservation Story from the Bottom of the World".