Water-level data used in submerged marine habitat mapping, Assateague Island National Seashore

This dataset shows 2 m depth contours within the study area.

This dataset shows the extent of bathymetry data collected during acoustic surveys completed within and adjacent to the boundaries of Cape Cod National Seashore (CACO) from 2014-2015. Full coverage sidescan and partial coverage bathymetry data were collected using an Edgetech 6205 Phase-Measuring Sidescan Sonar. In total, 668 hectares were mapped at primarily 20 – 40 meter line spacing and 50 meter swath range to allow overlap of lines.

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.

This dataset presents the raw and processed sidescan mosaic for 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 contains sediment grain-size classification data develop from during acoustic 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 sampling locations for the 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 volume of each sample.

Collection of benthic infauna and epifauna used a 0.04 m2 Ted Young Modified Van Veen grab. Three replicate benthic samples were collected at 23 sites to total 69 samples in Year 1. The samples were immediately sieved over a 0.5 mm mesh screen. The residue remaining on the screen was fixed in 3.7% formaldehyde solution in seawater, buffered with sodium borate and containing Rose Bengal to stain organisms. A fourth grab was collected for sediment analysis. Sediment for grain size analysis was wet-sieved through a 63μm-mesh sieve in distilled water with dispersant to disaggregate and separate the silt and clay fraction from the sand-sized fraction. Silt and clay mass was determined by drying a known volume of the water-particle mixture passing through the sieve. The sand fraction was dried and then sieved into the following size fractions: <63 µm (silt), 63-125 µm (very fine sand), 125-250 µm (fine sand), 250-500 µm (medium sand), 500-1000 µm (coarse sand), >1000 µm (very coarse sand). Each fraction was weighed. The mass of the <4φ fraction was further analyzed using a Spectrex model PC-2000 laser particle counter (Spectrex Corporation, Redwood City, CA) Counts of particles were obtained corresponding to these additional size categories: 5φ (4-8 µm very fine silt), and 6φ (16-31 µm, medium silt), 7φ (8-16 µm, fine silt), 8 φ ( 4-8 µm, very fine silt), and 9 φ (2-4 µm, clay). Particle counts were converted to mass by multiplying the fractional volume percent in each size category by the total mass of the <4φ fraction determined during wet sieving.

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).

Polygon shapefile showing the coverage area of the acoustic mapping at Sandy Hook, NJ between July 2015 and August 2015. The side scan sonar survey was done simultaneously with the bathymetry swath survey and used an EdgeTech Model 4125 Towfish bow-mounted from Lookdown at 400 and 900 kHz. The 4125 Towfish utilizes EdgeTech’s Full Spectrum CHIRP technology to produce higher resolution images than a non-CHIRP system. EdgeTech Discovery Software was used to acquire the side scan sonar data using the JSF format at a resolution of about 2.3 cm. All JSF files collected using EdgeTech’s Discover Software were processed using John Gann’s Chesapeake Technology SonarWiz5. Dimensions of contacts should be considered accurate to +/- 30% of the measured dimensions. This system also records the direct arrival intensity data.