Underwater sound observation using the Edokko Mark I as a platform of acoustic environment assessment for marine mineral resource development

group have developed an underwater sound recording device capable of observing underwater sound for approximately one year at a depth of 6,000 meters. We installed this device on the underwater explorer "Edokko Mark I (Type 365)," and obtained intermittent recording for about one year at the research station LE4, located about 160 km offshore south of Minami-Torishima Island, Japan, where marine mineral resources exist. In this study, we report on the newly developed underwater sound recording device and the results of the soundscape analysis.