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Modern techniques for imaging the ocean floor have considerably enhanced our understanding and interpretation of seafloor morphology and processes. Within the past decade significant advances in acoustic and optical instrument development such as MultiBeam EchoSounder (MBES) or Sonar (MBS) and Light Detecting And Ranging (LiDAR) ocean-bed sensing systems have provided scientists with high quality, high resolution digital data sets that can be used to produce photo-like images of the sea bed. Although these "pretty pictures" of the seabed are generally spectacular, other data such as MBES backscatter or side-scan sonar mosaics, seafloor sediment or rock samples, and photos or video need to be collected and interpreted to construct a map of substrate and potential benthic habitat types that will benefit management. In other words, since geology can generally be mapped more extensively, inexpensively, and comprehensively than biology, the geologic renderings of the sea floor may be used as surrogates, proxies, or predictors of biology (presence of species, assemblages, or ecosystems).
All mapping efforts should have a clear objective leading to a useful product that will address scientific hypotheses or will have application to management and policy goals. In the past 15 years we have been mapping the sea floor along the Pacific margin of North America to define and characterize demersal fish habitats. Although these data were collected with a fisheries habitat-mapping objective, the maps produced can now be used for many other objectives. To do so, a standardized and repetitive mapping scheme is required to produce maps for multiple purposes. To make our maps as useful as possible, and to be able to cover multiple objectives, we developed a habitat mapping attribute code that is intuitive, flexible, and querieable within a Geographic Information System (GIS). As long as the data are interpreted in great detail and the map attribute data can be accessed digitally, multiple uses of the interpreted maps are possible. Therefore, our maps once constructed for a groundfish fisheries sustainability management objective are now being used to assess and eventually manage such things as foraging (e.g., sand lance), abalone, and eelgrass habitats. Much of this information is being used for the establishment and monitoring of Marine Protected Areas (MPAs). In addition, dynamic sedimentologic and tectonic features are characterized in our maps, which provide important information in regard to non-living resources, including geologic hazards critical to any seafloor development.
In California (USA) the ocean- and bay-floors within State waters are being mapped using the most up-to-date technology. This type of activity is also occurring in the offshore and inland seas of Washington and Alaska states (USA), and in British Columbia (Canada). Maps of potential benthic habitats in these areas are being constructed using our attribute code.
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