A Seafloor Dataset for Bahía Almirante, Panama: Single-Beam Echosounder Depth, Acoustic Bottom Indices, and Ground-Truthing

Seafloor mapping data derived from acoustic measurements remain scarce for many coastal systems, including locations of active ecological research such as Bahía Almirante, Bocas del Toro, Panama. We present the first openly accessible sonar and ground-truth seafloor dataset for this area. Sonar data were collected from June 2019 to April 2022 using a commercially available Humminbird HELIX 10 CHIRP single-beam echosounder, providing water depth and two relative acoustic bottom indices (E1 and E2) associated with seafloor roughness and hardness, respectively. Survey lines covered the bay at a spacing of approximately 800 m, densified to ~400 m in areas of higher bathymetric relief and ~200 m within the channels connecting the bay to the open ocean. Ground-truth data were collected at 90 sites from October 2021 to July 2023 following a standardized, decision-based field protocol, and include site-level sonar data and qualitative substrate assessment (90 sites), photoquadrat imagery (58 sites), and sediment grain-size analysis where substrate and field conditions permitted (19 sites). All data are provided in standard, analysis-ready formats with full documentation to facilitate reuse and to support ongoing oceanographic, ecological, geological, and coastal management research in the Bocas del Toro Archipelago.