The Department of Marine Science and Fisheries (MSF) at the College of Agricultural and Marine Sciences (CAMS) hosted a workshop from December 17 – 19th 2018, to teach MSF Faculty and Staff how to use a side-scan sonar (SSS) to efficiently create images of large areas of the sea-floor.
The workshop was organized by Dr. Alyssa Marshell (MSF) with funding graciously received from His Majesty’s Trust Fund (HMTF) Strategic Grants to purchase the new side-scan sonar equipment from Deep Vison Sonar Systems (deepvison.se). The owner of Deep Vision, Mr. Uffe Langstrom, with assistance from a SSS expert, Dr. Kaveh Samimi-Namin (Naturalis Biodiversity Center, Netherlands), taught MSF Faculty and Staff how to effectively use the side-scan sonar. Day 1 of the workshop provided an introduction and background on how the sonar works, Day 2 was spent on the MSF Department boat, Al Jamiah, to test the new equipment and learn how to practically use the sonar to conduct sea-floor surveys in the field, and Day 3 focused on learning how to use the customized software to analyze the side-scan sonar data.
Side-scan sonars emit pulses down toward the sea-floor across a wide-angle while being towed from a boat. The sonar records the intensity of the acoustic reflections of the pulses from the sea-floor. When stitched together along the direction of motion, this data forms an image of the sea bottom within the coverage width of the pulse beam. Side-scan sonar is used to conduct surveys of the sea-floor, and in conjunction with sea-floor samples, it provides an understanding of the different types of materials and textures of the seabed. Side-scan sonar imagery is also a commonly used tool to detect obstructions on the seafloor that may be hazardous to shipping, or for sea-floor installations by the oil and gas industry. Additionally, the status of pipelines and cables on the seafloor can be investigated using side-scan sonar. Side-scan data are recorded along with GPS and depth data, which provides a picture of the structure of the seabed. Side-scan sonar can also be used for fisheries research, dredging operations and environmental studies.
The MSF department plans to start fieldwork in January 2019 using the side scan sonar to map Ministry of Agriculture and Fisheries Wealth (MAFW) artificial reef sites in the Al Batinah region. These side scan sonar maps of the artificial reef sites will help to assess the contribution of the sites to enhancing fisheries productivity in the region, a project generously funded by His Majesty’s Trust Fund (HMTF) Strategic Grants.