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America's Coral Reefs

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Caribbean Islands

Caribbean coral reefs have been affected considerably by global and local stressors. Massive, region-wide decline of corals across the entire Caribbean basin have been reported, with the average stony coral cover on reefs being reduced by 80%, from about 50% to 10% in three decades (Gardner et al. 2003).

‘Coral cover’ is a term used to represent the proportion of an area occupied by corals. In addition to reduced coral cover, there is reduced biological diversity, reduced reef structure (which provides fish and invertebrate habitat), and increased spatial and temporal extent of algae. These suggest a general pattern of decline and degradation of Caribbean coral reef ecosystems (Hughes 1994, Gardner et al. 2003, Jackson et al. 2014). Both short and long-term management actions are necessary to avoid further catastrophic damage.

Caribbean Coral Reef Partnership

The Caribbean Coral Reef Partnership (CCRP) is an interagency effort to protect coral reefs off the shores of Puerto Rico and the U.S. Virgin Islands (USVI). The Partnership was formed to facilitate a closer working relationship among agencies and coordinate more effective government strategies in protecting coral reefs in the Caribbean.

CCRP includes 13 federal and local agencies, including: Puerto Rico Department of Natural and Environmental Resources, Puerto Rico Environmental Quality Board, U.S. Virgin Islands Department of Planning and Natural Resources, Federal Highways Administration, National Oceanic and Atmospheric Administration (NOAA), National Park Service, U.S. Coast Guard, U.S. Department of Agriculture’s Natural Resources Conservation Service, EPA, U.S. Fish and Wildlife Service, U.S. Forest Service, U.S. Geological Survey, and U.S. Army Corps of Engineers.

Blue-striped grunt swimming over stony coral outcrop.Blue-striped grunt swimming over stony coral outcrop.The CCRP provides a leadership forum to foster collaboration among agencies with authority and jurisdiction to respond to identified local threats. The partnership works closely with USVI and Puerto Rico with a focus on priority watershed projects.

An important aspect of the CCRP is to provide information to EPA to advance Clean Water Act protections described in EPA Region 2’s Coral Protection Plan. Similarly, the CCRP provides input to all partner agencies to guide their plans for coral conservation and protection. The partnership is positioned to help respond to emerging threats because it can quickly assemble agency leaders to engage in executive-level discussions on emerging issues.

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Guánica Bay Watershed Partnership Initiative

The U.S. Coral Reef Task Force (USCRTF) launched the Guánica Bay Watershed Initiative in 2009. Located in the southwestern corner of Puerto Rico, the Guánica Bay watershed is highly altered from agriculture and human development. The purpose of this project is to reduce excessive sediment and nutrient runoff into coastal waters, which is affecting coral reef health.

USCRTF members are bringing their resources to work with local partners to implement restoration activities in the watershed. These activities will help reduce runoff of excessive sediment and nutrients onto coral reefs. The following projects are in progress:

  • Infrastructure removal and river stabilization
  • Restoration of the historic Guánica Lagoon
  • Construction of a six-acre wetlands treatment system for the Guánica sewage treatment plant
  • Hydroseeding 20 acres of high mountain sediment sources
  • Selection and planting of cover crop to transition from sun-grown to shade-grown coffee farms

Additional projects are intended to be implemented in the future, including corrective actions for failing septic systems and development of coral reef and ecological education opportunities.

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Water Quality Criteria

Biological Criteria Support in USVI

In 2010, USVI adopted narrative biological criteria (biocriteria) into its Water Quality Standards Regulations. Biocriteria describe the desired condition for coral reefs and apply to all marine and coastal waters of the USVI, including estuarine, mangrove, seagrass, coral reef, and other marine ecosystems. According to this criterion, all marine waters of USVI shall be of a sufficient quality to support a resident biological community, including coral reef communities.

EPA continues to work closely with USVI to encourage periodic coral monitoring, and to develop relationships between specific water quality parameters and coral condition. A long-term goal of this overall effort is to derive numeric biological criteria, allowing for more targeted assessments and potential restoration of coral reefs.

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Adoption of New/Revised Water Quality Standards by Puerto Rico and the USVI to Ensure Protection of Corals

For their survival, corals require a narrow range of environmental conditions and are primarily constrained by light, water temperature, salinity, and concentrations of nutrients (phosphorus and nitrogen).

In 2015, USVI adopted revised water quality standards for temperature and turbidity, applicable to areas where coral reefs are located. Puerto Rico is considering revising numerous water quality standards to increase protection of coral reefs during the upcoming triennial review of the Water Quality Standards Regulations. EPA continues to work closely with both Puerto Rico and USVI to encourage the adoption of additional new or revised water quality.

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Trash and Microplastics

EPA has launched a Trash-Free Waters (TFW) initiative in Puerto Rico. The TFW initiative serves as a catalyst for issue analysis, facilitated dialogue, strategic planning, and project implementation. This initiative also places a strong emphasis on collaboration. Through the TFW Partnership, EPA is helping agencies, states, municipalities, academia, and businesses work together to develop innovative aquatic trash management strategies. These strategies aim to achieve a goal of zero-trash loading by 2025.

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Florida’s coral reefs represent the third largest barrier reef ecosystem in the world. The Florida Reef Tract extends from St. Lucie Inlet in Martin County (north of Miami) to the Dry Tortugas west of the Florida Keys. Roughly two thirds of the Florida Reef Tract lie within Biscayne National Park and the Florida Keys National Marine Sanctuary (FKNMS).

Florida’s reefs have been in a state of decline for the last 40 years with many reefs losing more than half of their coral cover. In southeast Florida, coastal resources are under intense stress from high population densities and coastal development. Sediment and nutrient run-off, dredging for port improvement projects, overfishing, and damage from direct contact, are some of the issues facing Florida’s reefs.

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Florida Keys National Marine Sanctuary Water Quality Protection Program

EPA and the State of Florida co-administer the Florida Keys National Marine Sanctuary Water Quality Protection Program (WQPP)Exit. The WQPP is a 25-year collaborative effort by federal, state, and local governments, elected officials, non-government organizations, academia, and local citizens. These organizations work together to protect and improve water quality, coral reefs, and seagrasses to support fisheries and recreational opportunities.

Efforts that have been successful include improved wastewater and stormwater treatment, designation of no discharge zones, implementation of Clean Marina Programs, and restoration of residential canals. For example, EPA has been working with the State of Florida and Monroe County for over fifteen years to eliminate onsite septic systems and provide advanced wastewater or best available technology wastewater treatment to citizens residing on the 30 inhabited islands of the Florida Keys.

Approximately $750 million has gone into this effort, with the Keys nearing 90% completion of this goal.

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Coral Reef Evaluation and Monitoring Project (CREMP)

The Coral Reef Evaluation and Monitoring Project (CREMP)Exitwas established in 1995 as part of the Florida Keys National Marine Sanctuary’s Water Quality Protection Program (WQPP). CREMP monitors and records the status of coral reef conditions. The Project focuses its monitoring efforts on 40 reef sites in the Florida Keys National Marine Sanctuary.

CREMP assessments have been conducted annually at fixed sites since 1996. The data collected are compiled and compared to the results from the previous year in order to better identify changes and trends. The CREMP program provides valuable information on long-term temporal changes of stony corals, octocorals, sponges, and macroalgae within the Sanctuary to detect changes on an ecosystem-scale.

From 1996 to 2015, CREMP found that stony coral cover declined by 53.8% due to thermal stress, disease, and damage from hurricanes. The majority of coral bleaching events occurred during the 1997/1998 mass bleaching event, during times of higher ocean temperatures provoked by El Niño, and the 2010 cold-water event. In addition to declines in stony coral, CREMP found that sponges have also declined in the Florida Keys since 1996. This appears to have also been caused by thermal stress events and disease.

Data collected in 2015 showed a significant decline in stony coral cover from 7.04% in 2014 to 6.22% in 2015 due to massive bleaching. The change in coral cover (0.82%) marked the largest one year drop since the winter mortality event of 2009-2010.

The record warm ocean temperatures of 2014, 2015, and 2016 contributed to the worst global bleaching event since 1997-1998 when nearly 20% of the world’s coral was lost. This snaps a streak of four consecutive years in which small increases or no net loss of coral cover was observed in the Florida Keys.

While stony coral have been decreasing in the Florida Keys over the last ten years, there has been a steady increase in the cover of octocorals and sponges. Although similarly impacted by bleaching events and hurricanes, the octocorals are becoming more dominant due to their ability to recover quickly and colonize habitat vacated by the stony corals.

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Flower Garden Banks

Established in 1992, the Flower Garden Banks National Marine Sanctuary (FGBNMS)Exit is the only marine sanctuary located in the Gulf of Mexico. Situated along the edge of the continental shelf off the coasts of Texas and Louisiana, the FGBNMS includes underwater communities that rise from the depths of the Gulf of Mexico atop underwater salt domes. EPA participates on the Sanctuary’s Advisory Council.

The Sanctuary currently protects three separate areas: East Flower Garden Bank, West Flower Garden Bank, and Stetson Bank in water depths ranging from 200 to 500 feet. These are only three among dozens of banks scattered along the continental shelf of the northwestern Gulf of Mexico. These banks are part of a regional ecosystem, heavily influenced by current patterns within the Gulf and inflows from the Mississippi River watershed that drains two-thirds of the continental United States.

Researchers at the FGBNMS have recently seen a significant loss of invertebrates at the East Flower Garden Bank. In July 2016, divers found unprecedented numbers of dying stony corals, sponges, sea urchins, brittle stars, clams, and other organisms. Scientists are currently monitoring and researching the situation.

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More than 60% of U.S. coral reefs are found in the extended Hawaiian Island chain which stretches over 1,500 miles in the north central Pacific Ocean (USGS, 2002). The Northwestern Hawaiian Islands (NWHI) are a chain of ten small islands and atolls north and west of the eight main Hawaiian Islands and much of this area is encompassed by the Papahānaumokuākea Marine National MonumentExit. This is one of the largest Marine Protected Areas on the planet and it is managed by state and federal agencies.

The main Hawaiian Islands include over 140,000 acres of coral reef habitat. The types and variety vary from island to island, ranging from coral communities to fringing reefs, unique patch reefs, reef slopes, and barrier reefs. Historically, coral reefs have played an important role in Hawaiian culture and subsistence agriculture. Over time these practices have eroded due to cultural, political, and demographic changes that have affected water rights, land use, and land ownership, resulting in disrupted ecosystem functions and sustainable management practices over just a few generations.

Hawai‘i’s reefs remain extremely important as habitats, natural coastline buffers, sites for recreation and cultural practices, and as a key component of the marine economy. In addition to providing protection from large ocean swells and providing food for sustenance and commerce, it is estimated that the state’s coral reefs are worth $9-10 billion dollars and generate several hundred million dollars annually in added value to the state’s economy from marine tourism (Cesar and van Beukering, 2002).

Land-based pollution (i.e., solid and hazardous waste, sediment, nutrients, pathogens, pesticides), overfishing, coastal construction, and invasive species are the key threats to coral reefs in the Pacific. In addition, global threats, such as warning sea temperatures and changing chemistry may result in coral bleaching and harm to coral growth. This emphasizes the need to do everything possible to reduce local threats to coral reefs.

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Hawai‘i Coral Reef Working Group

EPA is a member of the Hawai‘i Coral Reef Working Group. The Hawai‘I Coral Reef Working Group is led by the State of Hawai‘i Department of Land and Natural Resources, Division of Aquatic resources, the primary agency responsible for coordinating coral reef management efforts in the main Hawaiian Islands.

The Coral Reef Working Group is comprised of state and federal agencies involved in coral reef management and strives to identify and address key threats to coral reefs. The group provides guidance to the State of Hawai‘i’s Coral Reef ProgramExitin the areas of program planning, community action and awareness, scientific research to inform ecosystem management, and on-the-ground projects.

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West Maui Ridge to Reef Initiative

The State of Hawai‘i’s Coral Reef Strategy identified the coral reef ecosystem along the West Maui region as a priority management area. The U.S. Coral Reef Task Force designated West Maui watersheds as a priority partnership in the Pacific in 2011. The West Maui Ridge to Reef (R2R) InitiativeExitis a watershed management effort involving multiple agencies and organizations to address adverse impacts to coral reefs in West Maui.

An integrated and comprehensive approach to reduce land-based sources of pollution is one of the most important steps to help restore coral reef ecosystems. The R2R Initiative builds on already established efforts underway and leverages resources across agencies and community groups to implement actions to reduce one of the key sources of reef decline – land-based sources of pollution. EPA serves on the Funding and Agency Support Team which is the leadership body for the R2R Initiative.

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Clean Water Act Funding

EPA awards annual Clean Water Act Section 319 funding to address nonpoint source water pollution to Hawai‘i Department of Health for projects to protect watersheds and coral reef health.

EPA has provided Wetland Program Development Grant funding to the University of Hawai‘i – Hawai‘i Institute of Marine Biology to examine linkages between watershed and adjacent coral reef condition and inform prioritization of watershed management interventions aimed at improving coral reefs.

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Kaua‘i Stormwater Settlement Agreement (Hawai‘i)

EPA has led strong Clean Water Act enforcement actions in Hawaiʻi which have helped protect coral reefs and deter further violations.

Clean Water Act violations resulting in sediment damage to a coral reefs on Kaua‘i, Hawai‘i, were resolved in a settlement agreement totaling more than $7.5 million involving the EPA, U.S. Department of Justice, the State of Hawai‘i, Kaua‘i County, and Earth Justice. The settlement includes $5.3 million to prevent erosion and restore streams at the construction site. All land restoration work required by the settlement agreement was completed in 2016.

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Large-Capacity Cesspool Closures

EPA has implemented a strategy to identify and close over 4,800 large capacity cesspools (LCC). Cesspools pose environmental and public health risks by releasing disease-causing pathogens and other contaminants to groundwater and coastal waters. Approximately 3,400 LCCs in Hawaiʻi have either been closed or outfitted with better wastewater management technology through regulatory authority or compliance assistance. Cesspool closure and wastewater upgrades at public beaches, parks, schools, plantation camps, and businesses will improve overall water quality for Hawai‘i’s coral reefs.

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Pacific Islands

The U.S.-affiliated Pacific islands, including the territories of American Samoa, the Commonwealth of the Northern Mariana Islands (CNMI), and Guam, as well as the Freely Associated States of the Marshall Islands, Palau, and the Federated States of Micronesia (FSM), face significant environmental challenges. Each island jurisdiction has its own local environmental agency working to protect public health and the environment.

Due to the challenges presented by their remote locations and limited land-based resources, the islands have a great need for better infrastructure to provide safe drinking water, treat sewage, and address garbage and hazardous waste. The Pacific Islands experience some of the biggest threats and impacts from rising sea levels, severe typhoons, coral bleaching, and ocean acidification. In addition, geo-political changes have heightened the strategic importance of U.S. Pacific Islands, as underscored by proposed additional military presence.

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Faga’alu Watershed Partnership Initiative

The Faga’alu watershed in American Samoa was identified as a priority watershed of the U.S. Coral Reef Task ForceExit in 2012. Working alongside NOAA, USGS, and American Samoa Environmental Protection Agency, U.S. EPA helped fund a nonpoint source pollution reduction project to cut sediment flowing into Faga’alu Bay. This was accomplished by installing sediment retention ponds and incorporating best management practices (BMPs) at an upstream quarry. Prior to implementing these BMPs, the quarry was releasing three times as much sediment into Faga’alu Bay.

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Clean Water Act Funding

EPA awards annual Clean Water Act funding to address nonpoint source water pollution to partner agencies in American Samoa, Guam, and the CNMI for projects to protect watersheds and coral reef health.

EPA has provided Wetland Program Development Grant funding to American Samoa to conduct water quality monitoring and assess the health of watersheds and their adjacent coral reefs. One of the goals is to use the monitoring data collected to produce a ridge-to-reef ecosystem health index for prioritizing implementation of management interventions.

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Guam Military Buildup

EPA is working with U.S. Navy, Guam, NOAA, U.S. Army Corps of Engineers, and U.S. Fish and Wildlife Service to minimize environmental impacts associated with the construction phase of the military buildup on the island. This includes the improvement of wastewater infrastructure. Environmental precautions will help the military protect coral reefs from pollution and water quality issues that may arise from construction activities.

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Guam Wastewater Spill Reduction

Guam, working with U.S. EPA and the U.S. Department of Justice, has reduced wastewater spills during 2004-2006 by more than 90% from the 2001-2002 spill levels. New sewer collector lines will be installed to improve Guam’s wastewater infrastructure. The improved infrastructure will prevent sewage overflows and protect coral reefs by eliminating excess nutrient loading to coastal waters.

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CNMI Coral Reefs Better Protected

The CNMI, with financial support from U.S. EPA, has reduced sediment loading to Lao Lao Bay, one of the premier tourist spots for diving on the island of Saipan. Sediment loading from the Lao Lao Bay watershed has been significantly reduced by installing stormwater infrastructure on selected roads within the watershed and implementing best management practices recommended in the 2006 CNMI and Guam Stormwater Management Manual.

The reduction in sediment loading improves water quality, better protects coral reefs and has continued to maintain the island as a strong destination for visiting scuba divers.

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