If we stop killing parrotfish we can bring back Caribbean coral reefs
Some countries are already taking action to protect coral grazing species. Barbuda is moving to ban all catches of parrotfish and grazing sea urchins while also planning to set aside one third of their coastal waters as marine reserves.
Credit: Ayana Johnson
Invasive species in the Caribbean have contributed to coral decline by breaking the delicate ecosystem balance.
With only about one-sixth of the original coral cover left, most Caribbean coral reefs may disappear in the next 20 years, primarily due to the loss of grazers in the region, according to the latest report by the Global Coral Reef Monitoring Network (GCRMN), the International Union for Conservation of Nature (IUCN) and the United Nations Environment Programme (UNEP).
The report, Status and Trends of Caribbean Coral Reefs: 1970-2012, is the most detailed and comprehensive study of its kind published to date – the result of the work of 90 experts over the course of three years. It contains the analysis of more than 35,000 surveys conducted at 90 Caribbean locations since 1970, including studies of corals, seaweeds, grazing sea urchins and fish.
The results show that the Caribbean corals have declined by more than 50% since the 1970s. But according to the authors, restoring parrotfish populations and improving other management strategies, such as protection from overfishing and excessive coastal pollution, could help the reefs recover and make them more resilient to future climate change impacts.
"The rate at which the Caribbean corals have been declining is truly alarming," says Carl Gustaf Lundin, Director of IUCN's Global Marine and Polar Programme. "But this study brings some very encouraging news: the fate of Caribbean corals is not beyond our control and there are some very concrete steps that we can take to help them recover."
Climate change has long been thought to be the main culprit in coral degradation. While it does pose a serious threat by making oceans more acidic and causing coral bleaching, the report shows that the loss of parrotfish and sea urchin – the area's two main grazers – has, in fact, been the key driver of coral decline in the region. An unidentified disease led to a mass mortality of the sea urchin in 1983 and extreme fishing throughout the 20th century has brought the parrotfish population to the brink of extinction in some regions. The loss of these species breaks the delicate balance of coral ecosystems and allows algae, on which they feed, to smother the reefs.
Reefs protected from overfishing, as well as other threats such as excessive coastal pollution, tourism and coastal development, are more resilient to pressures from climate change, according to the authors.
"Even if we could somehow make climate change disappear tomorrow, these reefs would continue their decline," says Jeremy Jackson, lead author of the report and IUCN's senior advisor on coral reefs. "We must immediately address the grazing problem for the reefs to stand any chance of surviving future climate shifts."
The report also shows that some of the healthiest Caribbean coral reefs are those that harbour vigorous populations of grazing parrotfish. These include the U.S. Flower Garden Banks National Marine Sanctuary in the northern Gulf of Mexico, Bermuda and Bonaire, all of which have restricted or banned fishing practices that harm parrotfish, such as fish traps and spearfishing. Other countries are following suit.
"Barbuda is about to ban all catches of parrotfish and grazing sea urchins, and set aside one-third of its coastal waters as marine reserves," says Ayana Johnson of the Waitt Institute's Blue Halo Initiative which is collaborating with Barbuda in the development of its new management plan. "This is the kind of aggressive management that needs to be replicated regionally if we are going to increase the resilience of Caribbean reefs."
Reefs where parrotfish are not protected have suffered tragic declines, including Jamaica, the entire Florida Reef Tract from Miami to Key West, and the U.S. Virgin Islands.
The Caribbean is home to 9% of the world's coral reefs, which are one of the most diverse ecosystems on the planet. Caribbean reefs, spanning a total of 38 countries, are vital to the region's economy. They generate more than US$ 3 billion annually from tourism and fisheries and over a hundred times more in other goods and services, on which more than 43 million people depend.
"The decline in corals started long before climate change began to affect reefs," says Terry Hughes, author of the 1994 study that predicted the current problems due to parrotfish removal. "This report confirms that vigorous populations of grazing parrotfish are a common attribute of the healthiest Caribbean coral reefs. These 'resilient reefs' have strong local protections that are strictly enforced and double or triple the average coral cover of the 14% seen throughout the Caribbean."
"Parrotfish populations are crucial to the very survival of coral reefs, but are being destroyed despite their enormous ecological and economic value" says Jerker Tamelander, head of the UNEP coral reef unit. "We urge Caribbean nations to work together and respond to the Caribbean coral reef crisis through joint actions, including protecting parrotfish under the Protocol on specially protected areas and wildlife of the Cartagena Convention."
Notes to editors
The report Status and Trends of Caribbean Coral Reefs: 1970-2012 was published by the GCRMN and IUCN, with the support from The International Coral Reef Initiative (ICRI), the ARC Centre of Excellence for Coral Reef Studies, United States State Department, United Nations Environment Programme (UNEP), Ministry of Economic Affairs of the Netherlands, Summit Foundation, McQuown Foundation and the Smithsonian Tropical Research Institute.
Key findings of the report:
Recommendations made in the report:
Executive Summary and full report, "Status and Trends of Caribbean Coral Reefs: 1970-2012": http://bit.ly/1puLHlp
High resolution photos: http://bit.ly/1qLdYmc
An 8-minute video, "From Despair to Repair," about the report's implications: http://www.iucn.org/?16050
The Global Coral Reef Monitoring Network (GCRMN) was established in 1994 to support the global call for action of the International Coral Reef Initiative (ICRI) to commit to increasing research and monitoring of coral reefs in order to provide the data needed to inform policy makers to sustain coral reefs and to strengthen management. Today, the GCRMN works through a global network of stakeholders to support the management and conservation of coral reefs. The work of GCRMN focuses on increasing the scientific understanding of the status and trends of coral reef ecosystems worldwide by making reef monitoring data publicly available, linking people and existing organizations, improving the communication among GCRMN members by providing information on network activities in order to strengthen the existing capacity across regions to manage coral reefs more efficiently while adapting to the effects of climate change. http://gcrmn.org/
IUCN, International Union for Conservation of Nature, helps the world find pragmatic solutions to our most pressing environment and development challenges. IUCN's work focuses on valuing and conserving nature, ensuring effective and equitable governance of its use, and deploying nature-based solutions to global challenges in climate, food and development. IUCN supports scientific research, manages field projects all over the world, and brings governments, NGOs, the UN and companies together to develop policy, laws and best practice. IUCN is the world's oldest and largest global environmental organization, with more than 1,200 government and NGO Members and almost 11,000 volunteer experts in some 160 countries. IUCN's work is supported by over 1,000 staff in 45 offices and hundreds of partners in public, NGO and private sectors around the world. http://www.iucn.org
The International Coral Reef Initiative (ICRI) is a unique environmental partnership that brings together stakeholders with the objective of sustainable use and conservation of coral reefs for future generations. The many partners, including governments, international environmental and development agencies, scientific associations, the private sector and NGOs, are dedicated to designing the best strategies to conserve the world's coral reef resources. http://www.icriforum.org/
About ARC Centre of Excellence for Coral Reef Studies
ARC Centre of Excellence for Coral Reef Studies was established in 2005 and is recognised as one of the world's premiere coral reef research organisations. Headquartered at James Cook University, the ARC Centre partnership includes the Australian National University, the University of Queensland and the University of Western Australia and leading international research centres. The ARC Centre of Excellence currently encompasses >250 researchers and graduate students, with ongoing research projects in 30 countries. The vision of the Centre is to provide the scientific knowledge necessary for understanding the world's coral reefs and their interaction with people in order to foster their sustainable use, secure the benefits they provide to tropical societies and economies, and enhance the effectiveness of coral reef management world-wide. http://www.coralcoe.org.au/
The United Nations Environment Programme (UNEP), established in 1972, is the voice for the environment within the United Nations system. UNEP acts as a catalyst, advocate, educator and facilitator to promote the wise use and sustainable development of the global environment. To accomplish this, UNEP works with a wide range of partners, including United Nations entities, international organizations, national governments, non-governmental organizations, the private sector and civil society. http://www.unep.org
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