Coral Reef Project Active
Explore the fascinating undersea world of coral reefs. Learn how we map, monitor, and model coral reefs so we can better understand, protect, and preserve our Nation's reefs.
Coral reefs are unique ecosystems of plants, animals, and their associated geological framework. Coral reefs cover less than 0.5 percent of the earth's surface, but are home to an estimated 25 percent of all marine species. Second only to tropical rainforests in size and complexity, some scientists estimate that more than one million species of plants and animals are associated with coral reefs. Coral reefs are also of great economic importance to those who live on or visit islands in the Pacific and Atlantic Oceans. Reefs shelter and provide nursery grounds for many commercially and culturally important species of fish and invertebrates, they protect the islands' harbors, beaches, and shorelines from erosion and wave damage by storms, and they are vital to the marine tourism industry. These diverse ecosystems provide valuable goods and services worth about $4 billion each year to the U.S.’s coastal communities. Yet, as important as coral reefs are, these ecosystems are being threatened worldwide.
More than 8,500 square miles (22,000 square kilometers) of coral reef habitat is found in U.S. waters. Most of these coral reefs still appear to be relatively healthy, but some areas of dead and dying coral have been found in recent years. The causes of this degradation are poorly known, but are probably in part related to human activities.
The U.S. Geological Survey (USGS), working closely with academic institutions, state, and other Federal agencies, is spearheading an effort to better understand the geologic and oceanographic controls on the structure and processes of our Nation's coral reef ecosystems.
This web site is a gateway to USGS studies of coral reefs. We focus on the geophysical processes that influence the health and sustainability of coral reefs. From this work we are gaining new insight into the structure of coral reefs, providing the basis for future monitoring, and understanding better both the influences of natural processes and impacts of human activities on coral reef health. These efforts will help to preserve and protect the biodiversity, health, and social and economic value of these remarkable habitats.
Read more coral reef facts.
Learn about our current studies by topic.
Climate Change and Land-use Histories
We are developing new and unique oceanographic and environmental archives from coral skeleton records to better understand the compounding effects of land-use and environmental change on coral reef health.
We are conducting geophysical and geochemical research to address questions about coastal groundwater-to-reef flow and coral reef health, with the goal of informing management decisions related to planning and implementing activities in priority watershed-coral reef systems.
Reef Hydrodynamics and Sediment Processes
We are developing a better understanding how tides, waves, currents, and both land- and reef-derived sediment influence the development of coral reefs and their adjacent shorelines.
Role of Reefs in Coastal Protection
We are combining ocean, engineering, ecologic, social, and economic modeling to provide a high-resolution, rigorous, spatially-explicit valuation of the coastal flood protection benefits provided by coral reefs and the cost effectiveness of reef restoration for enhancing those benefits.
Reef Resource Assessments - Planning for the Future
We are mapping and assessing all of the important geologic and oceanographic factors to identify those coral reefs most at risk and those reefs that are potentially the most resilient and the most likely to recover from natural and human-driven impacts.
Also, learn about our studies by location:
- Guam
- Hawai‛i
- Kaho‛olawe
- Kaua‛i
- Kwajalein Island
- Lāna‛i
- Maui
- Moloka‛i
- O‛ahu
- Puerto Rico
- Roi-Namur Island
- Tutuila
Please also see the associated Coral Reef Ecosystem Studies (CREST) Project website.
Our partners are numerous and include:
- U.S. Coral Reef Task Force (USCRTF)
- Department of the Interior
- Other Federal Partners
- State Partners
- Territorial and Commonwealth Partners
- Guam Division of Aquatic and Wildlife Resources
- Commonwealth of the Northern Mariana Islands Department of Land and Natural Resources
- American Samoa Department of Marine and Wildlife Resources
- Puerto Rico Department of Natural and Environmental Resources
- U.S. Virgin Islands Department of Planning and Natural Resources
- Academia
- University of California Santa Cruz - Institute of Marine Sciences
- University of Western Australia - Oceans Institute
- University of Puerto Rico at Mayaguez - Center for Applied Ocean Science & Engineering
- University of Hawaiʻi - Hawaiʻi Institute of Marine Biology
- Woods Hole Oceanographic Institution - Department of Geology and Geophysics
- Delft University of Technology - Department of Hydraulic Engineering
- Queen's University - Department of Civil Engineering
- University of Cantabria - Department of Sciences and Techniques in Water and Environment
- Non-governmental Organizations
Below are data releases associated with this project.
Below are multimedia items associated with this project.
Below is a list of our project publications.
Carbonate system parameters of an algal-dominated reef along west Maui
Nonhydrostatic and surfbeat model predictions of extreme wave run-up in fringing reef environments
Challenges of forecasting flooding on coral reef–lined coasts
Modeling fine-scale coral larval dispersal and interisland connectivity to help designate mutually-supporting coral reef marine protected areas: Insights from Maui Nui, Hawaii
Vulnerability of coral reefs to bioerosion from land-based sources of pollution
A Bayesian-based system to assess wave-driven flooding hazards on coral reef-lined coasts
Projected atoll shoreline and run-up changes in response to sea-level rise and varying large wave conditions at Wake and Midway Atolls, Northwestern Hawaiian Islands
Atoll groundwater movement and its response to climatic and sea-level fluctuations
The use of passive membrane samplers to assess organic contaminant inputs at five coastal sites in west Maui, Hawaii
Baseline assessments for coral reef community structure and demographics on West Maui
Rigorously valuing the role of coral reefs in coastal protection: An example from Maui, Hawaii, U.S.A.
Coastal circulation and water-column properties in the National Park of American Samoa, February–July 2015
Below are news stories associated with this project.
USGS Investigations of coral reefs are cooperative efforts, and our scientists are working in partnership and cooperation with the following organizations.
- Overview
Explore the fascinating undersea world of coral reefs. Learn how we map, monitor, and model coral reefs so we can better understand, protect, and preserve our Nation's reefs.
Coral reefs are unique ecosystems of plants, animals, and their associated geological framework. Coral reefs cover less than 0.5 percent of the earth's surface, but are home to an estimated 25 percent of all marine species. Second only to tropical rainforests in size and complexity, some scientists estimate that more than one million species of plants and animals are associated with coral reefs. Coral reefs are also of great economic importance to those who live on or visit islands in the Pacific and Atlantic Oceans. Reefs shelter and provide nursery grounds for many commercially and culturally important species of fish and invertebrates, they protect the islands' harbors, beaches, and shorelines from erosion and wave damage by storms, and they are vital to the marine tourism industry. These diverse ecosystems provide valuable goods and services worth about $4 billion each year to the U.S.’s coastal communities. Yet, as important as coral reefs are, these ecosystems are being threatened worldwide.
More than 8,500 square miles (22,000 square kilometers) of coral reef habitat is found in U.S. waters. Most of these coral reefs still appear to be relatively healthy, but some areas of dead and dying coral have been found in recent years. The causes of this degradation are poorly known, but are probably in part related to human activities.
The U.S. Geological Survey (USGS), working closely with academic institutions, state, and other Federal agencies, is spearheading an effort to better understand the geologic and oceanographic controls on the structure and processes of our Nation's coral reef ecosystems.
This web site is a gateway to USGS studies of coral reefs. We focus on the geophysical processes that influence the health and sustainability of coral reefs. From this work we are gaining new insight into the structure of coral reefs, providing the basis for future monitoring, and understanding better both the influences of natural processes and impacts of human activities on coral reef health. These efforts will help to preserve and protect the biodiversity, health, and social and economic value of these remarkable habitats.
Read more coral reef facts.
Learn about our current studies by topic.
Climate Change and Land-use Histories
We are developing new and unique oceanographic and environmental archives from coral skeleton records to better understand the compounding effects of land-use and environmental change on coral reef health.
We are conducting geophysical and geochemical research to address questions about coastal groundwater-to-reef flow and coral reef health, with the goal of informing management decisions related to planning and implementing activities in priority watershed-coral reef systems.
Reef Hydrodynamics and Sediment Processes
We are developing a better understanding how tides, waves, currents, and both land- and reef-derived sediment influence the development of coral reefs and their adjacent shorelines.
Role of Reefs in Coastal Protection
We are combining ocean, engineering, ecologic, social, and economic modeling to provide a high-resolution, rigorous, spatially-explicit valuation of the coastal flood protection benefits provided by coral reefs and the cost effectiveness of reef restoration for enhancing those benefits.
Reef Resource Assessments - Planning for the Future
We are mapping and assessing all of the important geologic and oceanographic factors to identify those coral reefs most at risk and those reefs that are potentially the most resilient and the most likely to recover from natural and human-driven impacts.
Also, learn about our studies by location:
- Guam
- Hawai‛i
- Kaho‛olawe
- Kaua‛i
- Kwajalein Island
- Lāna‛i
- Maui
- Moloka‛i
- O‛ahu
- Puerto Rico
- Roi-Namur Island
- Tutuila
Please also see the associated Coral Reef Ecosystem Studies (CREST) Project website.
Our partners are numerous and include:
- U.S. Coral Reef Task Force (USCRTF)
- Department of the Interior
- Other Federal Partners
- State Partners
- Territorial and Commonwealth Partners
- Guam Division of Aquatic and Wildlife Resources
- Commonwealth of the Northern Mariana Islands Department of Land and Natural Resources
- American Samoa Department of Marine and Wildlife Resources
- Puerto Rico Department of Natural and Environmental Resources
- U.S. Virgin Islands Department of Planning and Natural Resources
- Academia
- University of California Santa Cruz - Institute of Marine Sciences
- University of Western Australia - Oceans Institute
- University of Puerto Rico at Mayaguez - Center for Applied Ocean Science & Engineering
- University of Hawaiʻi - Hawaiʻi Institute of Marine Biology
- Woods Hole Oceanographic Institution - Department of Geology and Geophysics
- Delft University of Technology - Department of Hydraulic Engineering
- Queen's University - Department of Civil Engineering
- University of Cantabria - Department of Sciences and Techniques in Water and Environment
- Non-governmental Organizations
- Science
- Data
Below are data releases associated with this project.
Filter Total Items: 22No Result Found - Multimedia
Below are multimedia items associated with this project.
- Publications
Below is a list of our project publications.
Filter Total Items: 163Carbonate system parameters of an algal-dominated reef along west Maui
Constraining coral reef metabolism and carbon chemistry dynamics are fundamental for understanding and predicting reef vulnerability to rising coastal CO2 concentrations and decreasing seawater pH. However, few studies exist along reefs occupying densely inhabited shorelines with known input from land-based sources of pollution. The shallow coral reefs off Kahekili, West Maui, are exposed to nutriAuthorsNancy G. Prouty, Kimberly K. Yates, Nathan A. Smiley, Christopher Gallagher, Olivia Cheriton, Curt D. StorlazziNonhydrostatic and surfbeat model predictions of extreme wave run-up in fringing reef environments
The accurate prediction of extreme wave run-up is important for effective coastal engineering design and coastal hazard management. While run-up processes on open sandy coasts have been reasonably well-studied, very few studies have focused on understanding and predicting wave run-up at coral reef-fronted coastlines. This paper applies the short-wave resolving, Nonhydrostatic (XB-NH) and short-wavAuthorsChristopher H. Lashley, Dano Roelvink, Ap R. van Dongeren, Mark L. Buckley, Ryan J. LoweChallenges of forecasting flooding on coral reef–lined coasts
Understanding wave-driven coastal flooding is a challenging scientific problem; the need for forecasts is becoming more urgent because of sea level rise, climate change, and ever-growing coastal populations. The tools developed for sandy shorelines are generally not applicable to coral reef–lined coasts with their complex bathymetry, hydrodynamically rough reef platforms, steep and poorly sorted bAuthorsCurt D. StorlazziModeling fine-scale coral larval dispersal and interisland connectivity to help designate mutually-supporting coral reef marine protected areas: Insights from Maui Nui, Hawaii
Connectivity among individual marine protected areas (MPAs) is one of the most important considerations in the design of integrated MPA networks. To provide such information for managers in Hawaii, USA, a numerical circulation model was developed to determine the role of ocean currents in transporting coral larvae from natal reefs throughout the high volcanic islands of the Maui Nui island complexAuthorsCurt D. Storlazzi, Maarten van Ormondt, Yi-Leng Chen, Edwin P. L. EliasVulnerability of coral reefs to bioerosion from land-based sources of pollution
Ocean acidification (OA), the gradual decline in ocean pH and [ ] caused by rising levels of atmospheric CO2, poses a significant threat to coral reef ecosystems, depressing rates of calcium carbonate (CaCO3) production, and enhancing rates of bioerosion and dissolution. As ocean pH and [ ] decline globally, there is increasing emphasis on managing local stressors that can exacerbate the vulnerabiAuthorsNancy G. Prouty, Anne Cohen, Kimberly K. Yates, Curt D. Storlazzi, Peter W. Swarzenski, Darla WhiteA Bayesian-based system to assess wave-driven flooding hazards on coral reef-lined coasts
Many low-elevation, coral reef-lined, tropical coasts are vulnerable to the effects of climate change, sea level rise, and wave-induced flooding. The considerable morphological diversity of these coasts and the variability of the hydrodynamic forcing that they are exposed to make predicting wave-induced flooding a challenge. A process-based wave-resolving hydrodynamic model (XBeach Non-HydrostaticAuthorsS. G. Pearson, Curt D. Storlazzi, A. R. van Dongeren, M. F. S. Tissier, A. J. H. M. ReniersProjected atoll shoreline and run-up changes in response to sea-level rise and varying large wave conditions at Wake and Midway Atolls, Northwestern Hawaiian Islands
Atoll islands are dynamic features that respond to seasonal alterations in wave conditions and sea level. It is unclear how shoreline wave run-up and erosion patterns along these low elevation islands will respond to projected sea-level rise (SLR) and changes in wave climate over the next century, hindering communities' preparation for the future. To elucidate how these processes may respond to clAuthorsJames B. Shope, Curt D. Storlazzi, Ron HoekeAtoll groundwater movement and its response to climatic and sea-level fluctuations
Groundwater resources of low-lying atoll islands are threatened due to short-term and long-term changes in rainfall, wave climate, and sea level. A better understanding of how these forcings affect the limited groundwater resources was explored on Roi-Namur in the Republic of the Marshall Islands. As part of a 16-month study, a rarely recorded island-overwash event occurred and the island’s aquifeAuthorsFerdinand K. J. Oberle, Peter W. Swarzenski, Curt D. StorlazziThe use of passive membrane samplers to assess organic contaminant inputs at five coastal sites in west Maui, Hawaii
Five passive membrane samplers were deployed for 28 continuous days at select sites along and near the west Maui coastline to assess organic compounds and contaminant inputs to diverse, shallow coral reef ecosystems. Daily and weekly fluctuations in such inputs were captured on the membranes using integrative sampling. The distribution of organic compounds observed at these five coastal sites showAuthorsPamela L. Campbell, Nancy G. Prouty, Curt D. Storlazzi, Nicole D'antonioBaseline assessments for coral reef community structure and demographics on West Maui
The coastal and upslope terrains of West Maui have had a long history of impacts owing to more than a century of human activities. Resource extraction, agriculture, as well as residential and resort development have caused land-based pollution that impairs water quality and adversely impact the adjacent marine ecosystem. Today, West Maui’s coral reefs are chronically impacted by the effects of lanAuthorsBernardo Vargas-Angel, Darla White, Curt D. Storlazzi, Tova Callender, Paulo MaurinRigorously valuing the role of coral reefs in coastal protection: An example from Maui, Hawaii, U.S.A.
The degradation of coastal habitats, particularly coral reefs, raises risks by exposing communities to flooding hazards. The protective services of these natural defenses are not assessed in the same rigorous, economic terms as artificial defenses such as seawalls, and therefore often not considered in decision-making. Here we present a new methodology that combines economic, ecological, and enginAuthorsCurt D. Storlazzi, Borja G. Reguero, Erik Lowe, James B. Shope, Ann E. Gibbs, Mike Beck, Barry A. NickelCoastal circulation and water-column properties in the National Park of American Samoa, February–July 2015
There is little information on the oceanography in the National Park of American Samoa (NPSA). The transport pathways for potentially harmful constituents of land-derived runoff, as well as larvae and other planktonic organisms, are driven by nearshore circulation patterns. To evaluate the processes affecting coral reef ecosystem health, it is first necessary to understand the oceanographic procesAuthorsCurt D. Storlazzi, Olivia Cheriton, Kurt J. Rosenberger, Joshua B. Logan, Timothy B. Clark - Web Tools
- News
Below are news stories associated with this project.
Filter Total Items: 17 - Partners
USGS Investigations of coral reefs are cooperative efforts, and our scientists are working in partnership and cooperation with the following organizations.
Filter Total Items: 22