Sediment Profile Image (SPI) Analysis and Coastal/Marine Ecological Classification Standard (CMECS) Classification Data used to construct benthic habitat maps for FIIS. Sediment profile imagery (SPI) provides an in-situ perspective of the seafloor and associated characteristics. Specifically, the camera takes a profile photograph of the sediment-water interface, which offers information about the biological and environmental attributes of the surface of the seafloor, the substrate just below the seafloor, and the overlying water column. SPI imagery has been used as the basis for or to complement ecological studies for several decades (for further reading, refer to Germano et al., 2011; Solan et al., 2003; Germano et al., 1989). For this study, SPI images were collected to corroborate and complement the acoustic and grab sample data. Images were taken at each grab sample site and also along a series of planned transects designed to cross boundaries identified in the sidescan mosaics. All deployments of the camera were done in triplicate, resulting in six images per site (one deployment of the camera captures two images ten seconds apart). The images were processed and analyzed in Adobe Photoshop CS3. Color and contrast adjustments were applied to enhance the images for detection of features. Geological and biological features were identified and described through expert interpretation of the images, including relative grain size, bedforms, biogenic features, and presence of seagrass and organisms (identified to lowest taxonomic level). Furthermore, consistent settings were applied when taking penetration and apparent redox potential discontinuity (aRPD) measurements. The aRPD value indicates the depth at which the sediment transitions from being oxidized to reduced (Gerwing et al., 2017).

Sediment Grain Size and CMECS Classification Data used to construct benthic habitat maps for FIIS. The ground-truth surveys involved the collection of surficial grab samples of the seafloor, sediment profile imagery (SPI), and underwater video. The three instruments were deployed together, allowing for co-located datasets. Combined, these datasets help provide a thorough understanding of the study areas, as they capture sediment and biological community characteristics at various spatial scales and resolutions.

Sediment Grain Size and CMECS Classification Data used to construct benthic habitat maps for FIIS. The ground-truth surveys involved the collection of surficial grab samples of the seafloor, sediment profile imagery (SPI), and underwater video. The three instruments were deployed together, allowing for co-located datasets. Combined, these datasets help provide a thorough understanding of the study areas, as they capture sediment and biological community characteristics at various spatial scales and resolutions.

Sediment Profile Images (SPI) used to construct benthic habitat maps for FIIS. Sediment profile imagery (SPI) provides an in-situ perspective of the seafloor and associated characteristics. Specifically, the camera takes a profile photograph of the sediment-water interface, which offers information about the biological and environmental attributes of the surface of the seafloor, the substrate just below the seafloor, and the overlying water column. SPI imagery has been used as the basis for or to complement ecological studies for several decades (for further reading, refer to Germano et al., 2011; Solan et al., 2003; Germano et al., 1989). For this study, SPI images were collected to corroborate and complement the acoustic and grab sample data. Images were taken at each grab sample site and also along a series of planned transects designed to cross boundaries identified in the sidescan mosaics. All deployments of the camera were done in triplicate, resulting in six images per site (one deployment of the camera captures two images ten seconds apart). The images were processed and analyzed in Adobe Photoshop CS3. Color and contrast adjustments were applied to enhance the images for detection of features. Geological and biological features were identified and described through expert interpretation of the images, including relative grain size, bedforms, biogenic features, and presence of seagrass and organisms (identified to lowest taxonomic level). Furthermore, consistent settings were applied when taking penetration and apparent redox potential discontinuity (aRPD) measurements. The aRPD value indicates the depth at which the sediment transitions from being oxidized to reduced (Gerwing et al., 2017).

Benthic habitat maps were developed for the Otis Pike and Sunken Forest study areas following the top-down mapping approach, for which habitat map units are geologically defined based on the presumption that geologic environments or features contain distinct biological assemblages. The resulting habitats are classified according to the CMECS framework and are referred to as “biotopes.” The term “biotope” is specific in that it integrates biotic-abiotic characteristics to offer more ecologically meaningful information. In this study, biotopes reflect the relationship between macrofaunal communities and geological features of their associated environments within the defined map units. The resulting biotopes are considered preliminary because the relationships identified have not been repeatedly demonstrated over time, as this study represents the first of its kind within FIIS.

Benthic habitat maps were developed for the Otis Pike and Sunken Forest study areas following the top-down mapping approach, for which habitat map units are geologically defined based on the presumption that geologic environments or features contain distinct biological assemblages. The resulting habitats are classified according to the CMECS framework and are referred to as “biotopes.” The term “biotope” is specific in that it integrates biotic-abiotic characteristics to offer more ecologically meaningful information. In this study, biotopes reflect the relationship between macrofaunal communities and geological features of their associated environments within the defined map units. The resulting biotopes are considered preliminary because the relationships identified have not been repeatedly demonstrated over time, as this study represents the first of its kind within FIIS.

Benthic Macrofauna Sampling Data used to construct benthic habitat maps for FIIS. Data were collected during ground-truth surveys involving the collection of surficial grab samples of the seafloor and sediment profile imagery (SPI). Grab samples for analysis of macrofaunal community structure were collected in triplicate within Otis Pike and Sunken Forest to allow for more robust statistical analyses and to account for small-scale spatial variability that may be present. Single grab samples were taken at each site within East Breach to allow for a broader distribution of sample sites throughout the area. All samples were processed on board the vessel at the time of collection to ensure quality of data and avoid sample degradation. Each sample was sieved through a 0.5 mm mesh and captured macrofauna were retained and preserved in a Rose-Bengal solution to be processed at a designated lab. All individuals were counted and identified to the species level. SPI images were collected to corroborate and complement the acoustic and grab sample data. Images were taken at each grab sample site and also along a series of planned transects designed to cross boundaries identified in the sidescan mosaics. All deployments of the camera were done in triplicate, resulting in six images per site (one deployment of the camera captures two images ten seconds apart).

Habitat classification map based on surveys completed along the 58‐km long Assateague barrier island stretching from the Ocean City inlet in Maryland, down past Chincoteague Island in northern Virginia. The data was collected June 20th-25th, 2014 and May 12th - 21th, 2015. Full coverage side-scan sonar and partial coverage bathymetry data were collected using an EdgeTech 6205 Multiphase Echosounder. In total, 73 square kilometers were mapped at primarily at 100m line spacing and 80 m swath range per channel (to allow overlap between lines).

Habitat classification map based on surveys completed along the 58‐km long Assateague barrier island stretching from the Ocean City inlet in Maryland, down past Chincoteague Island in northern Virginia. The data was collected June 20th-25th, 2014 and May 12th - 21th, 2015. Full coverage side-scan sonar and partial coverage bathymetry data were collected using an EdgeTech 6205 Multiphase Echosounder. In total, 73 square kilometers were mapped at primarily at 100m line spacing and 80 m swath range per channel (to allow overlap between lines).

This dataset shows the cruise tracklines for the acoustic survey completed to the east of the new breachway created by Hurricane Sandy in 2012. The data was collected June 11th-16th, 2015.