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Staghorn coral, Acropora cervicornis, is a threatened species and the primary focus of western Atlantic reef restoration efforts to date. We compared linear extension, calcification rate, and skeletal density of nursery-raised A. cervicornis branches reared for 6 months either on blocks attached to substratum or hanging from PVC trees in the water column. We demonstrate that branches grown on the substratum had significantly higher skeletal density, measured using computerized tomography, and lower linear extension rates compared to water-column fragments. Calcification rates determined with buoyant weighing were not statistically different between the two grow-out methods, but did vary among coral genotypes. Whereas...
Categories: Publication; Types: Citation; Tags: Coral Reefs
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A long-term study of the scleractinian coral Acropora palmata in the US Virgin Islands (USVI) showed that diseases, particularly white pox, are limiting the recovery of this threatened species. Colonies of A. palmata in Haulover Bay, within Virgin Islands National Park, St. John, were examined monthly in situ for signs of disease and other stressors from January 2003 through December 2009. During the study, 89.9 % of the colonies (n = 69) exhibited disease, including white pox (87 %), white band (13 %), and unknown (9 %). Monthly disease prevalence ranged from 0 to 57 %, and disease was the most significant cause of complete colony mortality (n = 17). A positive correlation was found between water temperature and...
Categories: Publication; Types: Citation; Tags: Coral Reefs
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The fringing reef off southern Molokai, Hawaii, is currently being studied as part of a multi-disciplinary project led by the US Geological Survey. As part of this study, modeling and field observations were utilized to help understand the physical controls on reef morphology and the distribution of different coral species. A model was developed that calculates wave-induced hydrodynamic forces on corals of a specific form and mechanical strength. From these calculations, the wave conditions under which specific species of corals would either be stable or would break due to the imposed wave-induced forces were determined. By combining this hydrodynamic force-balance model with various wave model output for different...
Categories: Publication; Types: Citation; Tags: Coral Reefs
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Radiometric age dating of reef cores acquired at the Dry Tortugas coral reef ecosystem (DTCRE) was merged with lidar topographic mapping to examine Holocene reef development linked to spatial variation in growth and erosion under the control of sea level. Analysis of variance of lidar topography confirmed the presence of three distinct terraces on all three major DTCRE banks (Loggerhead Bank, Garden Bank, and Pulaski Bank). Reef building on the middle terrace (T2) began atop Pleistocene edifices on Loggerhead Bank by 8.0 ka (thousands of years ago) and on Garden Bank by 7.2 ka at elevations of about −16.0 m and −11.9 m, respectively, relative to present mean sea level. Following this initiation at different elevations,...
Categories: Publication; Types: Citation; Tags: Coral Reefs
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This dataset depicts relative erosion rate derived for all land draining above the Mesoamerican reef. It is a function of slope, land cover type, precipitation and soil type. The indicators developed by the Reefs at Risk in the Caribbean project enable detailed comparative analyses of threats on many scales. The Reefs at Risk indicators are a simplification of human activities and complex natural processes. This data set was derived at the World Resources Institute for input to the sedimentation and pollution from watershed based sources threat analysis. Agriculture, though important to economic development and food security, is a source of increased sediment, nutrient, and pesticide runoff. Threats from sedimentation...
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Using basins derived from a hydrologically-corrected 30m resolution DEM as a unit for summary statistics, we provide a series of indicators focused on land-based sources of threat within the US Virgin Islands and Puerto Rico. This includes indicators of a) the relative vulnerability of the land to erosion (based on slope, precipitation and soil erodibility); b) the relative erosion potential (REP) of the land, based on the relative vulnerability of the land, coupled with the current land cover type; c) the sediment delivery rate for each basin (percentage of eroded which reaches the river mouth); d) estimated sediment delivery for the basin, given current land use;
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Grid reflects the estimated frequency of severe thermal stress (NOAA Bleaching Alert Level 2) for decade 2030. Values are a percent (as integer) of the decade in which the grid cell would experience severe thermal stress under an IPCC "business-as-usual" emissions scenario. The specific indicator used in the model was the frequency (number of years in the decade) that the bleaching threshold is reached at least once. Frequencies were adjusted to account for historical sea surface temperature variability. Values range from 0 to 100. See the Reefs at Risk Revisited report and technical notes for more information.
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To capture cumulative threat in a given location, the four threats in the Reefs at Risk Caribbean analysis - coastal development, marine-based, sedimentation and overfishing - were integrated into a single index - the Reefs at Risk Threat Index.
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To capture cumulative threat in a given location, the four threats in the Reefs at Risk Caribbean analysis - coastal development, marine-based, sedimentation and overfishing - were integrated into a single index - the Reefs at Risk Threat Index.
These data are netcdf files of the projected timing of the onset of thermal stress severe enough (>8 Degree Heating Weeks) to cause coral bleaching 2x per decade and 10x per decade (annual) under emissions scenarios RCP8.5 and RCP4.5. The projected timing (a year between 2006 and 2100) is the data value. Values are only shown for the ~60,000 four-km pixels where coral reefs are known to occur.
This Project Snapshot provides a brief overview of the project "Coral reef resilience to climate change in the Commonwealth of the Northern Mariana Islands".
Reducing coral reef vulnerability to climate change requires that managers understand and support the natural resilience of coral reefs. We define coral reef resilience as: the capacity of a reef to resist and/or recover from disturbance given its probable exposure regime, and maintain provision of ecosystem goods and services. Spatial variation in exposure to disturbance and the resilience of reefs in the face of those disturbances will determine the fate of coral reefs within management jurisdictions. This project sought to: (1) undertake ecological resilience assessments in the Commonwealth of the Northern Mariana Islands (CNMI), which is in the west Pacific near Guam, and (2) collaboratively develop a decision-support...
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OBIS-USA brings together marine biological occurrence data – recorded observations of identifiable marine species at a known time and place, collected primarily from U.S. Waters or with U.S. funding. Coordinated by the Science Analytics and Synthesis (SAS) Program of the United States Geological Survey (USGS), OBIS-USA, strives to meet national data integration and dissemination needs for marine data about organisms and ecosystems. OBIS-USA is part of an international data sharing network (Ocean Biogeographic Information System, OBIS) coordinated by the Intergovernmental Oceanographic Commission, of UNESCO (United Nations Educational, Science and Cultural Organization) International Oceanographic Data and Information...
Tags: Arctic Ocean, Atlantic Ocean, Bay of Fundy, Beaufort Sea, Bering Sea, All tags...
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The rugosity or complexity of the seafloor has been shown to be an important ecological parameter for fish, algae, and corals. Historically, rugosity has been measured either using simple and subjective manual methods such as ‘chain-and-tape’ or complicated and expensive geophysical methods. Here, we demonstrate the application of structure-from-motion (SfM) photogrammetry to generate high-resolution, three-dimensional bathymetric models of a fringing reef from existing underwater video collected to characterize the seafloor. SfM techniques are capable of achieving spatial resolution that can be orders of magnitude greater than large-scale lidar and sonar mapping of coral reef ecosystems. The resulting data provide...
Categories: Publication; Types: Citation; Tags: Coral Reefs


map background search result map search result map Estimated Frequency of Severe Thermal Stress in the 2030s under an IPCC business-as-usual emissions scenario Caribbean Reefs at Risk Threat Index (polygon) Mesoamerican Relative Erosion Rate Puerto Rico Watershed Indicators by Basin Caribbean Reefs at Risk Index (points) Puerto Rico Watershed Indicators by Basin Mesoamerican Relative Erosion Rate Caribbean Reefs at Risk Index (points) Caribbean Reefs at Risk Threat Index (polygon) Estimated Frequency of Severe Thermal Stress in the 2030s under an IPCC business-as-usual emissions scenario