This dataset summarizes the species information derived from ground-truth survey conducted along Assateague Island National Seashore in October 2014 and October 2015. The ground-truth survey consisted of grab samples taken with a modified Young grab sampler. Grab samples were taken at each site. The attribute table of this dataset contains information about the grab samples, including the name and coordinates for each sample site, date of collection, and the species composition of each sample.

This dataset contains metrics of benthic assemblages taken before (pre) and after (post) barrier island restoration of the Mississippi Barrier Islands, which included sand placement on Cat and Ship Islands. The U.S. Fish and Wildlife Service considers the barrier islands along the Mississippi-Alabama coast as critical habitats for certain threated and endangered shorebird species. Barrier islands are inherently dynamic environments, facing frequent natural disturbances and undergoing rapid change. Understanding the distribution and community responses of benthic communities is critical for predicting the impact that restoration efforts and natural disturbances will have on shorebird foraging habits in the Mississippi Barrier Islands. Data were collected at both reference and restoration sites in 2011, 2015, 2020, 2023. Sites were selected based on shorebird foraging habitat, proximity to sand placement, and potential sand borrow sites. The data provided here includes wet biomass, raw density and richness, mean density and richness, and species percent abundance. These data will be used to inform the Mississippi Coastal Improvements Program (MsCIP) Monitoring and Adaptive Management Plan (MAMP).

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.

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.

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).

These data present the processed bathymetry mosaic for FIIS. The bathymetry data was collected June 11th-16th, 2015. The acoustic sonar survey was conducted using a EdgeTech 6205, a Multi-Phase Echo sounder system. This combined bathymetry and dual-frequency sidescan sonar system is optimized for shallow water surveying and is capable of acquiring bathymetry swath widths up to 8x the water depth. The sonar system was bow-mounted to a 28-ft pontoon survey vessel customized for shallow water surveying, including having a draft of less than one foot. Data was collected using GeoDas software developed by Ocean Imaging Consultants (OIC) and monitored topside in real-time to ensure quality of data and full-coverage sidescan was being achieved. The data were collected in association with an Applanix POS MV system to assure positional accuracy and to correct for vessel motion (pitch, roll, heave). The survey was designed to acquire full-coverage sidescan data and partial coverage bathymetry. As such, the survey was composed of parallel track lines with line spacing of 35 to 50 m and a sonar swath range of 50 m (25 m per side) to ensure overlap with adjacent lines. The raw sidescan and bathymetry records were processed using OIC CleanSweep software (Version 3.8.0, Build #263). For bathymetry, the processing following standard techniques of first correcting for tide, sound velocity, and vessel motion. Filters were then applied to remove outlier soundings. The resulting mosaic presents water depths of the survey area. All of the acoustic data were examined manually to confirm quality and accuracy. The horizontal coordinate system was set to UTM Zone 18N and bathymetry data was processed to 50cm pixel resolution.

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).

This dataset contains ground-truth sampling locations and data collected in support of Submerged Marine Habitat Mapping at Fire Island National Seashore. This ESRI file geodatabase contains six feature classes: benthic macrofaunal data, field notes, CMECS classification based on sediment, raw sediment data, SPI analysis, and CMECS classification based on SPI data.

This dataset shows the NPS park boundary for FIIS within Moriches Bay. The boundary was manually delineated from the boundary illustrated on NOAA chart 12352.