Benthic Single-Beam Acoustic

Contributing Partners:

Get It Now

RoxAnn transect lines in Rehoboth Bay, Delaware. Orange areas are unconsolidated sediments and green areas are macroalgae.

The NOAA Office for Coastal Management's single-beam acoustic benthic habitat data were developed using the RoxAnn seabed classification instrument. Multiple echo returns were analyzed for bottom hardness and roughness. These parameters were used, along with calibration information, to classify the substrate and identify biological communities. Single-beam acoustic data are often used to examine transition zones between habitats or in areas too turbid and shallow for other technologies. A non-tidally corrected depth was also recorded.

Data Specifications

  • Area of Coverage: Varies by project. Normally ranges from minimum depths of -1 meter to -30 meters. Project extents range from individual bay systems to smaller focus areas within larger projects in Delaware and Florida.
  • Date(s) Available: Vary by location, ranging from 1999 to 2001
  • Format: ESRI point shapefile
  • Resolution: Planimetric resolution is 10 percent of the depth
  • Minimal Mapping Unit: No minimum mapping unit for this type of data, but interpolated grids would have a specific cell size determined by transect spacing and habitat heterogeneity
  • Accuracy: 85 percent for all points


  • Developed in close cooperation with state and local partners to ensure a high degree of accuracy and applicability
  • Classified according to the Florida System for Classification of Habitats in Estuarine and Marine Environments (SCHEME)
  • Collected using the RoxAnn Groundmaster system
  • Collected along transect lines oriented to cover the project area or to cross transition zones across habitats
  • Interpreted based on acoustic signals and calibrated with ground observations

Data available in:

  • Delaware - Rehobeth Bay
  • Florida - Apalachicola Bay and Dry Tortugas

Notes and Limitations: RoxAnn data are normally collected through transect sampling. The data are collected in a systematic pattern distributed through the project area and require some interpolation to generate a comprehensive data set. Interpolations of these data should be used with caution due to potentially large, non-sampled areas that are present within the output data. Users are encouraged to develop or obtain higher-detail data for non-sampled areas within an interpolated output.


Techniques for Spatial Analysis and Visualization of Benthic Mapping Data
Describes spatial concepts important to data analysis, such as scale, interpolation, and data format

Tools and Techniques for the Acquisition of Estuarine Benthic Habitat Data
Examines the various technologies available for benthic mapping and provides guidance for collecting source data for mapping

Summary View of Acoustic Classification Survey Technique
Presents information on data coverage, scale, and resolution of single-beam classification system technology

Coastal and Marine Ecological Classification Standard
Provides a comprehensive national framework for organizing information about coasts and oceans and their living systems