Multiscale Terrain Analysis of Multibeam Bathymetry Data for Habitat Mapping on the Continental Slope

Abstract

Multibeam surveys can provide detailed bathymetry data for the continental slope from which quantitative descriptors of the seabed terrain (e.g., slope) may be obtained. We illustrate the value of these descriptors for benthic habitat mapping, and highlight the advantages of multiscale analysis. We examine the application of these descriptors as predictor variables for species distribution models, which are particularly valuable in the deep sea where opportunities to directly survey the benthic fauna remain limited. Our initial models are encouraging and suggest that wider adoption of these methods may assist the delivery of ecologically relevant information to marine resource managers.

Keywords:

• Multibeam bathymetry
• terrain analysis
• scale
• habitat suitability modelling
• continental slope

Acknowledgements

The Irish National Seabed Survey is managed by the Geological Survey of Ireland (GSI). The authors wish to thank the GSI for making the data available, to NUI, Galway for use in this study. We also extend our appreciation to all involved in the collection of ROV-video data used in this study during cruise CE0505 of the R. V. Celtic Explorer. We are grateful to Page Valentine and colleagues at the United States Geological Survey for providing the macro for calculation of the Terrain Ruggedness Index and for discussions in relation to its use. This research was funded under Cycle 3 of the Program for Research in Third Level Institutions by the Higher Education Authority of Ireland and administered by the Martin Ryan Institute in NUI, Galway. AJG is partially funded by the European Commission's Sixth Framework Programme HERMES project, EC contract no GOCE-CT-2005–511234 under the priority ‘Sustainable Development, Global Change and Ecosystems.