Benthic Habitat Mapping in the Olympic Coast National Marine Sanctuary
Steven S. Intelmann1, and G.R. Cochrane2
1Olympic Coast National Marine Sanctuary, NOAA
2Coastal and Marine Geology Program, USGS
In September 2002, side scan sonar was used to image a portion of the sea floor in the northern OCNMS and was mosaiced at 1-meter pixel resolution using 100 kHz data collected at 300-meter range scale. Video from a remotely-operated vehicle (ROV), bathymetry data, sedimentary samples, and sonar mapping have been integrated to describe geological and biological aspects of habitat and polygon features have been created and attributed with a hierarchical deep-water marine benthic classification scheme (Greene et al. 1999).
The data can be used with geographic information system (GIS) software for display, query, and analysis. Textural analysis of the sonar images provided a relatively automated method for delineating substrate into three broad classes representing soft, mixed sediment, and hard bottom. Microhabitat and presence of certain biologic attributes were also populated into the polygon features, but strictly limited to areas where video groundtruthing occurred. Further groundtruthing work in specific areas would improve confidence in the classified habitat map.
Keywords: Benthic, habitat mapping, sediment classification, side scan sonar, textural analysis, Olympic Coast National Marine Sanctuary, essential fish habitat, groundtruthing