Mapping seabed biotopes at Hastings Shingle Bank, eastern English Channel. Part 1. Assessment using sidescan sonar

• Published in: Journal of the Marine Biological Association of the United Kingdom Vol. 84; no. 3; pp. 481 - 488
• Main Authors: Brown, Craig J., Hewer, Alison J., Meadows, William J., Limpenny, David S., Cooper, Keith M., Rees, Hubert L.
• Format: Journal Article
• Language: English
• Published: Cambridge, UK Cambridge University Press 01.06.2004
• Subjects: Acoustics; Animal and plant ecology; Animal, plant and microbial ecology; Benthic communities; Biological and medical sciences; Biotopes; Camcorders; Cameras; Construction industry; Fisheries; Fundamental and applied biological sciences. Psychology; Laboratories; Marine; Ocean floor; Research Article; Sea water ecosystems; Sediments; Sonar; Spatial distribution; Synecology; Topography; English Channel; Atlantic Ocean; North Atlantic; United Kingdom > UK; ANE, Europe, English Channel; British Isles, England, Kent, Hastings; ANE, English Channel, Hastings Shingle Bank; Marine environment; Cartography; Biotope; Benthic organism; Hydrobiology; Habitat; Acoustic method; Benthic zone
• ISSN: 0025-3154; 1469-7769
• DOI: 10.1017/S002531540400949Xh

A multi-technique approach was used to map the spatial distribution of seabed biotopes (i.e. physical habitats and their associated benthic assemblages) in the vicinity of Hastings Shingle Bank in the eastern English Channel, part of which is licensed for the extraction of marine aggregates for the construction industry. An area of seabed, approximately 12×4 km in size, was surveyed using a high-resolution sidescan sonar system, and a mosaic of the output was produced, covering 100% of the survey area. The area was then divided into acoustically distinct regions based on the sidescan sonar data, and the benthic communities and sediment types within each of the regions were ground-truthed using a Hamon grab fitted with a video camera, and using a heavy duty 2-m beam trawl. Additional information concerning the seabed was obtained through the application of video and photographic techniques. Sediments within the survey area ranged from cobbles and coarse gravels on the Shingle Bank, to various grades of sands to the north and south. Analysis of faunal data revealed the presence of statistically distinct biological assemblages within each acoustic region. Using all available data, four discrete biotopes were identified and their spatial distribution mapped across the survey area.