David Zawada, Ph.D. (Former Employee)
Science and Products
Filter Total Items: 56
SQUID-5 structure-from-motion point clouds, bathymetric maps, orthomosaics, and underwater photos of coral reefs in Florida, 2019 SQUID-5 structure-from-motion point clouds, bathymetric maps, orthomosaics, and underwater photos of coral reefs in Florida, 2019
The new structure-from-motion (SfM) quantitative underwater imaging device with five cameras (SQUID-5) was tested in July 2019 at Crocker Reef in the Florida Keys. The SQUID-5 was developed to meet the unique challenges of collecting SfM underwater imagery, including multiple cameras with different perspectives, accurate geographic locations of images, accurate and precise scaling of...
Seafloor Elevation Change From 2004 to 2016 at Looe Key, Florida Keys Seafloor Elevation Change From 2004 to 2016 at Looe Key, Florida Keys
The U.S. Geological Survey (USGS) St. Petersburg Coastal and Marine Science Center conducted research to quantify bathymetric changes at Looe Key coral reef near Big Pine Key, Florida, within a 16.4 square-kilometer area between 2004 and 2016. USGS staff used light detection and ranging (lidar)-derived data acquired by the U.S. Army Corps of Engineers (USACE) Joint Airborne Lidar...
Projected Seafloor Elevation Along the Florida Reef Tract From Big Pine Key to Marquesas Key, Florida-75 Years From 2011 Based on Historical Rates of Mean Erosion Projected Seafloor Elevation Along the Florida Reef Tract From Big Pine Key to Marquesas Key, Florida-75 Years From 2011 Based on Historical Rates of Mean Erosion
The U.S. Geological Survey (USGS) St. Petersburg Coastal and Marine Science Center conducted research to quantify the combined effect of all constructive and destructive processes on modern coral reef ecosystems by projecting future regional-scale changes in seafloor elevation for several sites along the Florida Reef Tract, Florida (FL) including the shallow seafloor along Key West, FL...
Projected Seafloor Elevation Along the Florida Reef Tract From Port St. Lucie to Marquesas Key, Florida-100 Years From 2001 Based on Historical Rates of Mean Erosion Projected Seafloor Elevation Along the Florida Reef Tract From Port St. Lucie to Marquesas Key, Florida-100 Years From 2001 Based on Historical Rates of Mean Erosion
The U.S. Geological Survey (USGS) St. Petersburg Coastal and Marine Science Center conducted research to quantify the combined effect of all constructive and destructive processes on modern coral reef ecosystems by projecting future regional-scale changes in seafloor elevation along the Florida Reef Tract, Florida (FL). USGS staff used historical bathymetric point data from the 1930's...
Projected Seafloor Elevation Along the Florida Reef Tract From Port St. Lucie to Marquesas Key, Florida-50 Years From 2001 Based on Historical Rates of Mean Erosion Projected Seafloor Elevation Along the Florida Reef Tract From Port St. Lucie to Marquesas Key, Florida-50 Years From 2001 Based on Historical Rates of Mean Erosion
The U.S. Geological Survey (USGS) St. Petersburg Coastal and Marine Science Center conducted research to quantify the combined effect of all constructive and destructive processes on modern coral reef ecosystems by projecting future regional-scale changes in seafloor elevation along the Florida Reef Tract, Florida (FL). USGS staff used historical bathymetric point data from the 1930's...
Projected Seafloor Elevation Along the Florida Reef Tract From Port St. Lucie to Marquesas Key, Florida-75 Years From 2001 Based on Historical Rates of Mean Erosion Projected Seafloor Elevation Along the Florida Reef Tract From Port St. Lucie to Marquesas Key, Florida-75 Years From 2001 Based on Historical Rates of Mean Erosion
The U.S. Geological Survey (USGS) St. Petersburg Coastal and Marine Science Center conducted research to quantify the combined effect of all constructive and destructive processes on modern coral reef ecosystems by projecting future regional-scale changes in seafloor elevation along the Florida Reef Tract, Florida (FL). USGS staff used historical bathymetric point data from the 1930's...
Projected Seafloor Elevation Along the Florida Reef Tract From Port St. Lucie to Marquesas Key, Florida-25 Years From 2001 Based on Historical Rates of Mean Erosion Projected Seafloor Elevation Along the Florida Reef Tract From Port St. Lucie to Marquesas Key, Florida-25 Years From 2001 Based on Historical Rates of Mean Erosion
The U.S. Geological Survey (USGS) St. Petersburg Coastal and Marine Science Center conducted research to quantify the combined effect of all constructive and destructive processes on modern coral reef ecosystems by projecting future regional-scale changes in seafloor elevation along the Florida Reef Tract, Florida (FL). USGS staff used historical bathymetric point data from the 1930's...
Projected Seafloor Elevation Along the Florida Reef Tract From Big Pine Key to Marquesas Key, Florida-50 Years From 2011 Based on Historical Rates of Mean Erosion Projected Seafloor Elevation Along the Florida Reef Tract From Big Pine Key to Marquesas Key, Florida-50 Years From 2011 Based on Historical Rates of Mean Erosion
The U.S. Geological Survey (USGS) St. Petersburg Coastal and Marine Science Center conducted research to quantify the combined effect of all constructive and destructive processes on modern coral reef ecosystems by projecting future regional-scale changes in seafloor elevation for several sites along the Florida Reef Tract, Florida (FL) including the shallow seafloor along Key West, FL...
Projected Seafloor Elevation Along the Florida Reef Tract From Big Pine Key to Marquesas Key, Florida-25 Years From 2011 Based on Historical Rates of Mean Erosion Projected Seafloor Elevation Along the Florida Reef Tract From Big Pine Key to Marquesas Key, Florida-25 Years From 2011 Based on Historical Rates of Mean Erosion
The U.S. Geological Survey (USGS) St. Petersburg Coastal and Marine Science Center conducted research to quantify the combined effect of all constructive and destructive processes on modern coral reef ecosystems by projecting future regional-scale changes in seafloor elevation for several sites along the Florida Reef Tract, Florida (FL) including the shallow seafloor along Key West, FL...
Seafloor Elevation Change From 2016 to 2017 at Crocker Reef, Florida Keys-Impacts From Hurricane Irma Seafloor Elevation Change From 2016 to 2017 at Crocker Reef, Florida Keys-Impacts From Hurricane Irma
The U.S. Geological Survey (USGS) St. Petersburg Coastal and Marine Science Center conducted research to quantify bathymetric changes at Crocker Reef near Islamorada, Florida, within a 33.6 square-kilometer area following Hurricane Irma in September 2017. USGS staff used light detection and ranging (lidar)-derived data acquired by the National Oceanic and Atmospheric Administration (NOAA...
Projected Seafloor Elevation Along the Florida Reef Tract From Big Pine Key to Marquesas Key, Florida-100 Years From 2011 Based on Historical Rates of Mean Erosion Projected Seafloor Elevation Along the Florida Reef Tract From Big Pine Key to Marquesas Key, Florida-100 Years From 2011 Based on Historical Rates of Mean Erosion
The U.S. Geological Survey (USGS) St. Petersburg Coastal and Marine Science Center conducted research to quantify the combined effect of all constructive and destructive processes on modern coral reef ecosystems by projecting future regional-scale changes in seafloor elevation for several sites along the Florida Reef Tract, Florida (FL) including the shallow seafloor along Key West, FL...
Multibeam Bathymetry Data Collected in December 2017, February and March 2018 at Looe Key, the Florida Keys Multibeam Bathymetry Data Collected in December 2017, February and March 2018 at Looe Key, the Florida Keys
The U.S. Geological Survey St. Petersburg Coastal and Marine Science Center (USGS SPCMSC), collected multibeam bathymetry data at Looe Key in the Florida Keys during 3 separate survey legs, December 2017, February 2018 and March 2018, as a part of the Ecosystem Processes impacting Coastal Change project (EPIC) in an effort to assess sediment accumulation within the survey area. This USGS...
Filter Total Items: 26
Comparing bacterial community composition between healthy and white plague-like disease states in Orbicella annularis using PhyloChip™ G3 microarrays Comparing bacterial community composition between healthy and white plague-like disease states in Orbicella annularis using PhyloChip™ G3 microarrays
Coral disease is a global problem. Diseases are typically named or described based on macroscopic changes, but broad signs of coral distress such as tissue loss or discoloration are unlikely to be specific to a particular pathogen. For example, there appear to be multiple diseases that manifest the rapid tissue loss that characterizes ‘white plague.’ PhyloChip™ G3 microarrays were used...
Authors
Christina Kellogg, Yvette M. Piceno, Lauren Tom, Todd DeSantis, Michael Gray, David G. Zawada, Gary Andersen
Possible return of Acropora cervicornis at Pulaski Shoal, Dry Tortugas National Park, Florida Possible return of Acropora cervicornis at Pulaski Shoal, Dry Tortugas National Park, Florida
Seabed classification is essential to assessing environmental associations and physical status in coral reef ecosystems. At Pulaski Shoal in Dry Tortugas National Park, Florida, nearly continuous underwater-image coverage was acquired in 15.5 hours in 2009 along 70.2 km of transect lines spanning ~0.2 km2. The Along-Track Reef-Imaging System (ATRIS), a boat-based, high-speed, digital...
Authors
Barbara Lidz, David G. Zawada
Habitat use of breeding green turtles Chelonia mydas tagged in Dry Tortugas National Park: Making use of local and regional MPAs Habitat use of breeding green turtles Chelonia mydas tagged in Dry Tortugas National Park: Making use of local and regional MPAs
Use of existing marine protected areas (MPAs) by far-ranging marine turtles can be determined using satellite telemetry. Because of a lack of information on MPA use by marine turtles in the Gulf of Mexico, we used satellite transmitters in 2010 and 2011 to track movements of 11 adult female breeding green turtles (Chelonia mydas) tagged in Dry Tortugas National Park (DRTO), in the Gulf...
Authors
Kristen Hart, David G. Zawada, Ikuko Fujisaki, Barbara Lidz
PhyloChipTM microarray comparison of sampling methods used for coral microbial ecology PhyloChipTM microarray comparison of sampling methods used for coral microbial ecology
Interest in coral microbial ecology has been increasing steadily over the last decade, yet standardized methods of sample collection still have not been defined. Two methods were compared for their ability to sample coral-associated microbial communities: tissue punches and foam swabs, the latter being less invasive and preferred by reef managers. Four colonies of star coral, Montastraea...
Authors
Christina Kellogg, Yvette M. Piceno, Lauren Tom, Todd DeSantis, David G. Zawada, Gary L. Andersen
Fractal analysis of the Navassa Island seascape Fractal analysis of the Navassa Island seascape
This release provides the numerical results of the fractal analyses discussed in Zawada and others (2010) for the Navassa Island reefscape. The project represents the continuation of a U.S. Geological Survey (USGS) research effort begun in 2006 (Zawada and others, 2006) to understand the patterns and scalability of roughness and topographic complexity from individual corals to complete...
Authors
David G. Zawada
Topographic complexity and roughness of a tropical benthic seascape Topographic complexity and roughness of a tropical benthic seascape
Topographic complexity is a fundamental structural property of benthic marine ecosystems that exists across all scales and affects a multitude of processes. Coral reefs are a prime example, for which this complexity has been found to impact water flow, species diversity, nutrient uptake, and wave-energy dissipation, among other properties. Despite its importance, only limited assessments...
Authors
David G. Zawada, Clifford J. Hearn, Gregory Piniak
Theme section on “Mesophotic coral ecosystems: Characterization, ecology, and management” Theme section on “Mesophotic coral ecosystems: Characterization, ecology, and management”
Mesophotic coral ecosystems (MCEs) are characterized by the presence of light-dependent corals and associated communities that are typically found at depths ranging from 30 to 40 m and extending to over 150 m in tropical and subtropical regions. The dominant communities providing structural habitat in the mesophotic zone can be comprised of coral, sponge, and algal species. Because...
Authors
Lara Hinderstein, John Marr, Felix Martinez, Michael Dowgiallo, Richard Puglise, R. Pyle, David Zawada, R. Appeldoorn
Geomorphology of mesophotic coral ecosystems: Current perspectives on morphology, distribution, and mapping strategies Geomorphology of mesophotic coral ecosystems: Current perspectives on morphology, distribution, and mapping strategies
This paper presents a general review of the distribution of mesophotic coral ecosystems (MCEs) in relationship to geomorphology in US waters. It was specifically concerned with the depth range of 30–100 m, where more than 186,000 km2 of potential seafloor area was identified within the US Gulf of Mexico/Florida, Caribbean, and main Hawaiian Islands. The geomorphology of MCEs was largely...
Authors
S. D. Locker, R. Armstrong, Timothy Battista, John J. Rooney, C. Sherman, David G. Zawada
Detailed seafloor habitat mapping to enhance marine-resource management Detailed seafloor habitat mapping to enhance marine-resource management
Pictures of the seafloor capture important information about the sediments, exposed geologic features, submerged aquatic vegetation, and animals found in a given habitat. With the emergence of marine protected areas (MPAs) as a favored tactic for preserving coral reef resources, knowledge of essential habitat components is paramount to designing effective management strategies...
Authors
David G. Zawada, Kristen Hart
Inter-nesting habitat-use patterns of loggerhead sea turtles: Enhancing satellite tracking with benthic mapping Inter-nesting habitat-use patterns of loggerhead sea turtles: Enhancing satellite tracking with benthic mapping
The loggerhead sea turtle Caretta caretta faces declining nest numbers and bycatches from commercial longline fishing in the southeastern USA. Understanding spatial and temporal habitat-use patterns of these turtles, especially reproductive females in the neritic zone, is critical for guiding management decisions. To assess marine turtle habitat use within the Dry Tortugas National Park...
Authors
Kristen Hart, David G. Zawada, Ikuko Fujisaki, Barbara Lidz
Applying New Methods to Diagnose Coral Diseases Applying New Methods to Diagnose Coral Diseases
Coral disease, one of the major causes of reef degradation and coral death, has been increasing worldwide since the 1970s, particularly in the Caribbean. Despite increased scientific study, simple questions about the extent of disease outbreaks and the causative agents remain unanswered. A component of the U.S. Geological Survey Coral Reef Ecosystem STudies (USGS CREST) project is...
Authors
Christina Kellogg, David G. Zawada
A new towed platform for the unobtrusive surveying of benthic habitats and organisms A new towed platform for the unobtrusive surveying of benthic habitats and organisms
Maps of coral ecosystems are needed to support many conservation and management objectives, as well as research activities. Examples include ground-truthing aerial and satellite imagery, characterizing essential habitat, assessing changes, and monitoring the progress of restoration efforts. To address some of these needs, the U.S. Geological Survey developed the Along-Track Reef-Imaging...
Authors
David G. Zawada, P.R. Thompson, J. Butcher
Science and Products
Filter Total Items: 56
SQUID-5 structure-from-motion point clouds, bathymetric maps, orthomosaics, and underwater photos of coral reefs in Florida, 2019 SQUID-5 structure-from-motion point clouds, bathymetric maps, orthomosaics, and underwater photos of coral reefs in Florida, 2019
The new structure-from-motion (SfM) quantitative underwater imaging device with five cameras (SQUID-5) was tested in July 2019 at Crocker Reef in the Florida Keys. The SQUID-5 was developed to meet the unique challenges of collecting SfM underwater imagery, including multiple cameras with different perspectives, accurate geographic locations of images, accurate and precise scaling of...
Seafloor Elevation Change From 2004 to 2016 at Looe Key, Florida Keys Seafloor Elevation Change From 2004 to 2016 at Looe Key, Florida Keys
The U.S. Geological Survey (USGS) St. Petersburg Coastal and Marine Science Center conducted research to quantify bathymetric changes at Looe Key coral reef near Big Pine Key, Florida, within a 16.4 square-kilometer area between 2004 and 2016. USGS staff used light detection and ranging (lidar)-derived data acquired by the U.S. Army Corps of Engineers (USACE) Joint Airborne Lidar...
Projected Seafloor Elevation Along the Florida Reef Tract From Big Pine Key to Marquesas Key, Florida-75 Years From 2011 Based on Historical Rates of Mean Erosion Projected Seafloor Elevation Along the Florida Reef Tract From Big Pine Key to Marquesas Key, Florida-75 Years From 2011 Based on Historical Rates of Mean Erosion
The U.S. Geological Survey (USGS) St. Petersburg Coastal and Marine Science Center conducted research to quantify the combined effect of all constructive and destructive processes on modern coral reef ecosystems by projecting future regional-scale changes in seafloor elevation for several sites along the Florida Reef Tract, Florida (FL) including the shallow seafloor along Key West, FL...
Projected Seafloor Elevation Along the Florida Reef Tract From Port St. Lucie to Marquesas Key, Florida-100 Years From 2001 Based on Historical Rates of Mean Erosion Projected Seafloor Elevation Along the Florida Reef Tract From Port St. Lucie to Marquesas Key, Florida-100 Years From 2001 Based on Historical Rates of Mean Erosion
The U.S. Geological Survey (USGS) St. Petersburg Coastal and Marine Science Center conducted research to quantify the combined effect of all constructive and destructive processes on modern coral reef ecosystems by projecting future regional-scale changes in seafloor elevation along the Florida Reef Tract, Florida (FL). USGS staff used historical bathymetric point data from the 1930's...
Projected Seafloor Elevation Along the Florida Reef Tract From Port St. Lucie to Marquesas Key, Florida-50 Years From 2001 Based on Historical Rates of Mean Erosion Projected Seafloor Elevation Along the Florida Reef Tract From Port St. Lucie to Marquesas Key, Florida-50 Years From 2001 Based on Historical Rates of Mean Erosion
The U.S. Geological Survey (USGS) St. Petersburg Coastal and Marine Science Center conducted research to quantify the combined effect of all constructive and destructive processes on modern coral reef ecosystems by projecting future regional-scale changes in seafloor elevation along the Florida Reef Tract, Florida (FL). USGS staff used historical bathymetric point data from the 1930's...
Projected Seafloor Elevation Along the Florida Reef Tract From Port St. Lucie to Marquesas Key, Florida-75 Years From 2001 Based on Historical Rates of Mean Erosion Projected Seafloor Elevation Along the Florida Reef Tract From Port St. Lucie to Marquesas Key, Florida-75 Years From 2001 Based on Historical Rates of Mean Erosion
The U.S. Geological Survey (USGS) St. Petersburg Coastal and Marine Science Center conducted research to quantify the combined effect of all constructive and destructive processes on modern coral reef ecosystems by projecting future regional-scale changes in seafloor elevation along the Florida Reef Tract, Florida (FL). USGS staff used historical bathymetric point data from the 1930's...
Projected Seafloor Elevation Along the Florida Reef Tract From Port St. Lucie to Marquesas Key, Florida-25 Years From 2001 Based on Historical Rates of Mean Erosion Projected Seafloor Elevation Along the Florida Reef Tract From Port St. Lucie to Marquesas Key, Florida-25 Years From 2001 Based on Historical Rates of Mean Erosion
The U.S. Geological Survey (USGS) St. Petersburg Coastal and Marine Science Center conducted research to quantify the combined effect of all constructive and destructive processes on modern coral reef ecosystems by projecting future regional-scale changes in seafloor elevation along the Florida Reef Tract, Florida (FL). USGS staff used historical bathymetric point data from the 1930's...
Projected Seafloor Elevation Along the Florida Reef Tract From Big Pine Key to Marquesas Key, Florida-50 Years From 2011 Based on Historical Rates of Mean Erosion Projected Seafloor Elevation Along the Florida Reef Tract From Big Pine Key to Marquesas Key, Florida-50 Years From 2011 Based on Historical Rates of Mean Erosion
The U.S. Geological Survey (USGS) St. Petersburg Coastal and Marine Science Center conducted research to quantify the combined effect of all constructive and destructive processes on modern coral reef ecosystems by projecting future regional-scale changes in seafloor elevation for several sites along the Florida Reef Tract, Florida (FL) including the shallow seafloor along Key West, FL...
Projected Seafloor Elevation Along the Florida Reef Tract From Big Pine Key to Marquesas Key, Florida-25 Years From 2011 Based on Historical Rates of Mean Erosion Projected Seafloor Elevation Along the Florida Reef Tract From Big Pine Key to Marquesas Key, Florida-25 Years From 2011 Based on Historical Rates of Mean Erosion
The U.S. Geological Survey (USGS) St. Petersburg Coastal and Marine Science Center conducted research to quantify the combined effect of all constructive and destructive processes on modern coral reef ecosystems by projecting future regional-scale changes in seafloor elevation for several sites along the Florida Reef Tract, Florida (FL) including the shallow seafloor along Key West, FL...
Seafloor Elevation Change From 2016 to 2017 at Crocker Reef, Florida Keys-Impacts From Hurricane Irma Seafloor Elevation Change From 2016 to 2017 at Crocker Reef, Florida Keys-Impacts From Hurricane Irma
The U.S. Geological Survey (USGS) St. Petersburg Coastal and Marine Science Center conducted research to quantify bathymetric changes at Crocker Reef near Islamorada, Florida, within a 33.6 square-kilometer area following Hurricane Irma in September 2017. USGS staff used light detection and ranging (lidar)-derived data acquired by the National Oceanic and Atmospheric Administration (NOAA...
Projected Seafloor Elevation Along the Florida Reef Tract From Big Pine Key to Marquesas Key, Florida-100 Years From 2011 Based on Historical Rates of Mean Erosion Projected Seafloor Elevation Along the Florida Reef Tract From Big Pine Key to Marquesas Key, Florida-100 Years From 2011 Based on Historical Rates of Mean Erosion
The U.S. Geological Survey (USGS) St. Petersburg Coastal and Marine Science Center conducted research to quantify the combined effect of all constructive and destructive processes on modern coral reef ecosystems by projecting future regional-scale changes in seafloor elevation for several sites along the Florida Reef Tract, Florida (FL) including the shallow seafloor along Key West, FL...
Multibeam Bathymetry Data Collected in December 2017, February and March 2018 at Looe Key, the Florida Keys Multibeam Bathymetry Data Collected in December 2017, February and March 2018 at Looe Key, the Florida Keys
The U.S. Geological Survey St. Petersburg Coastal and Marine Science Center (USGS SPCMSC), collected multibeam bathymetry data at Looe Key in the Florida Keys during 3 separate survey legs, December 2017, February 2018 and March 2018, as a part of the Ecosystem Processes impacting Coastal Change project (EPIC) in an effort to assess sediment accumulation within the survey area. This USGS...
Filter Total Items: 26
Comparing bacterial community composition between healthy and white plague-like disease states in Orbicella annularis using PhyloChip™ G3 microarrays Comparing bacterial community composition between healthy and white plague-like disease states in Orbicella annularis using PhyloChip™ G3 microarrays
Coral disease is a global problem. Diseases are typically named or described based on macroscopic changes, but broad signs of coral distress such as tissue loss or discoloration are unlikely to be specific to a particular pathogen. For example, there appear to be multiple diseases that manifest the rapid tissue loss that characterizes ‘white plague.’ PhyloChip™ G3 microarrays were used...
Authors
Christina Kellogg, Yvette M. Piceno, Lauren Tom, Todd DeSantis, Michael Gray, David G. Zawada, Gary Andersen
Possible return of Acropora cervicornis at Pulaski Shoal, Dry Tortugas National Park, Florida Possible return of Acropora cervicornis at Pulaski Shoal, Dry Tortugas National Park, Florida
Seabed classification is essential to assessing environmental associations and physical status in coral reef ecosystems. At Pulaski Shoal in Dry Tortugas National Park, Florida, nearly continuous underwater-image coverage was acquired in 15.5 hours in 2009 along 70.2 km of transect lines spanning ~0.2 km2. The Along-Track Reef-Imaging System (ATRIS), a boat-based, high-speed, digital...
Authors
Barbara Lidz, David G. Zawada
Habitat use of breeding green turtles Chelonia mydas tagged in Dry Tortugas National Park: Making use of local and regional MPAs Habitat use of breeding green turtles Chelonia mydas tagged in Dry Tortugas National Park: Making use of local and regional MPAs
Use of existing marine protected areas (MPAs) by far-ranging marine turtles can be determined using satellite telemetry. Because of a lack of information on MPA use by marine turtles in the Gulf of Mexico, we used satellite transmitters in 2010 and 2011 to track movements of 11 adult female breeding green turtles (Chelonia mydas) tagged in Dry Tortugas National Park (DRTO), in the Gulf...
Authors
Kristen Hart, David G. Zawada, Ikuko Fujisaki, Barbara Lidz
PhyloChipTM microarray comparison of sampling methods used for coral microbial ecology PhyloChipTM microarray comparison of sampling methods used for coral microbial ecology
Interest in coral microbial ecology has been increasing steadily over the last decade, yet standardized methods of sample collection still have not been defined. Two methods were compared for their ability to sample coral-associated microbial communities: tissue punches and foam swabs, the latter being less invasive and preferred by reef managers. Four colonies of star coral, Montastraea...
Authors
Christina Kellogg, Yvette M. Piceno, Lauren Tom, Todd DeSantis, David G. Zawada, Gary L. Andersen
Fractal analysis of the Navassa Island seascape Fractal analysis of the Navassa Island seascape
This release provides the numerical results of the fractal analyses discussed in Zawada and others (2010) for the Navassa Island reefscape. The project represents the continuation of a U.S. Geological Survey (USGS) research effort begun in 2006 (Zawada and others, 2006) to understand the patterns and scalability of roughness and topographic complexity from individual corals to complete...
Authors
David G. Zawada
Topographic complexity and roughness of a tropical benthic seascape Topographic complexity and roughness of a tropical benthic seascape
Topographic complexity is a fundamental structural property of benthic marine ecosystems that exists across all scales and affects a multitude of processes. Coral reefs are a prime example, for which this complexity has been found to impact water flow, species diversity, nutrient uptake, and wave-energy dissipation, among other properties. Despite its importance, only limited assessments...
Authors
David G. Zawada, Clifford J. Hearn, Gregory Piniak
Theme section on “Mesophotic coral ecosystems: Characterization, ecology, and management” Theme section on “Mesophotic coral ecosystems: Characterization, ecology, and management”
Mesophotic coral ecosystems (MCEs) are characterized by the presence of light-dependent corals and associated communities that are typically found at depths ranging from 30 to 40 m and extending to over 150 m in tropical and subtropical regions. The dominant communities providing structural habitat in the mesophotic zone can be comprised of coral, sponge, and algal species. Because...
Authors
Lara Hinderstein, John Marr, Felix Martinez, Michael Dowgiallo, Richard Puglise, R. Pyle, David Zawada, R. Appeldoorn
Geomorphology of mesophotic coral ecosystems: Current perspectives on morphology, distribution, and mapping strategies Geomorphology of mesophotic coral ecosystems: Current perspectives on morphology, distribution, and mapping strategies
This paper presents a general review of the distribution of mesophotic coral ecosystems (MCEs) in relationship to geomorphology in US waters. It was specifically concerned with the depth range of 30–100 m, where more than 186,000 km2 of potential seafloor area was identified within the US Gulf of Mexico/Florida, Caribbean, and main Hawaiian Islands. The geomorphology of MCEs was largely...
Authors
S. D. Locker, R. Armstrong, Timothy Battista, John J. Rooney, C. Sherman, David G. Zawada
Detailed seafloor habitat mapping to enhance marine-resource management Detailed seafloor habitat mapping to enhance marine-resource management
Pictures of the seafloor capture important information about the sediments, exposed geologic features, submerged aquatic vegetation, and animals found in a given habitat. With the emergence of marine protected areas (MPAs) as a favored tactic for preserving coral reef resources, knowledge of essential habitat components is paramount to designing effective management strategies...
Authors
David G. Zawada, Kristen Hart
Inter-nesting habitat-use patterns of loggerhead sea turtles: Enhancing satellite tracking with benthic mapping Inter-nesting habitat-use patterns of loggerhead sea turtles: Enhancing satellite tracking with benthic mapping
The loggerhead sea turtle Caretta caretta faces declining nest numbers and bycatches from commercial longline fishing in the southeastern USA. Understanding spatial and temporal habitat-use patterns of these turtles, especially reproductive females in the neritic zone, is critical for guiding management decisions. To assess marine turtle habitat use within the Dry Tortugas National Park...
Authors
Kristen Hart, David G. Zawada, Ikuko Fujisaki, Barbara Lidz
Applying New Methods to Diagnose Coral Diseases Applying New Methods to Diagnose Coral Diseases
Coral disease, one of the major causes of reef degradation and coral death, has been increasing worldwide since the 1970s, particularly in the Caribbean. Despite increased scientific study, simple questions about the extent of disease outbreaks and the causative agents remain unanswered. A component of the U.S. Geological Survey Coral Reef Ecosystem STudies (USGS CREST) project is...
Authors
Christina Kellogg, David G. Zawada
A new towed platform for the unobtrusive surveying of benthic habitats and organisms A new towed platform for the unobtrusive surveying of benthic habitats and organisms
Maps of coral ecosystems are needed to support many conservation and management objectives, as well as research activities. Examples include ground-truthing aerial and satellite imagery, characterizing essential habitat, assessing changes, and monitoring the progress of restoration efforts. To address some of these needs, the U.S. Geological Survey developed the Along-Track Reef-Imaging...
Authors
David G. Zawada, P.R. Thompson, J. Butcher
*Disclaimer: Listing outside positions with professional scientific organizations on this Staff Profile are for informational purposes only and do not constitute an endorsement of those professional scientific organizations or their activities by the USGS, Department of the Interior, or U.S. Government