Benthic Habitat Mapping with Multi-beam Sonar in Newman Sound, Terra Nova National Park, Newfoundland
The objective of this project was to characterize and map the seafloor habitats of Newman Sound, a fjord in Terra Nova National Park, Newfoundland. A multi-beam sonar system was used to map depth and seabed slope and the acoustic reflectance intensity (backscatter) of the seabed. A shallow sub-bottom profiler was also used to investigate the sediment layers immediately below the seabed. Interpretations about the nature of the seabed were made based on the type and intensity of the signal returns from the multi-beam sonar and sub-bottom profiler.
These interpretations were tested on the ground by collecting sediment, invertebrates and algae with a benthic grab. Videos were also collected by various methods, Eight substrate types were classified. Characteristic biological assemblages were associated with these substrates, which allowed these habitats to be identified. Substrate and habitat maps were then created for the whole fjord by supervised classification of the multi-beam sonar data in a geographic information system (GIS).