High-resolution multibeam data were collected as part of the 'SUSTAIN-BAY' project focused on ecosystem survey with RV Tarajoq (October 2023). The goal of the project is to link the information from the seafloor mapping, benthic biodiversity, fish, and shellfish with the physical oceanography, as well as with surface primary production and vertical export as food source for the benthos in the unexplored area of Melville Bay. Data were collected using a hull-mounted multibeam echo sounder Teledyne Reson SeaBat 7160 operated at 44 kHz with 512 beams per ping. Positioning and movements of the vessel are transferred directly from the Applanix POS MV Ocean Master receiving data from an Inertial Motion Unit and two Trimble GNSS (DGPS) antennas. The accuracy of the observations is generally within 0.5 to 2 m horizontally and up to 0.03 degrees roll, pitch, and heading of the vessel (Applanix, 2020). Sound Velocity Profiles (SVP) were collected every c. 2 hours (along with water temperature) to correct the effect of sonar beam refraction due to water density changes.Bathymetry data were collected continuously as transit lines - the gaps in data are caused by stopping for ground-truthing stations. Data were acquired and SVP-corrected using the QPS Qinsy software and were processed for spike removal using the QPS Qimera software (www.qps.nl). Tide correction was not applied. Bathymetry data were gridded at 10 x 10 m resolution.

These data should not be used for navigational purposes.Acknowledgement:Funding was provided by the Dansk Center for Havforskning, Nordic Council of Ministers (AG-Fisk), and Greenland Institute of Natural Resources.