An initial ecological characterization of mesopelagic fauna at Johnston Atoll and Musicians Seamounts Regional Studies in Marine Science

The mesopelagic region (200–1000 m) hosts a wide variety of organisms in a concentrated layer known as the deep scattering layer (DSL). Much of the mesopelagic region in the central North Pacific remains unexplored, limiting ecosystem considerations in fisheries management and other applications. The National Oceanic and Atmospheric Administration (NOAA) Office of Ocean Exploration and Research used NOAA Ship Okeanos Explorer to conduct two expeditions in the region, one to Johnston Atoll and the other to Musicians Seamounts. During these expeditions, a remotely operated vehicle collected video and CTD environmental data while the ship collected active acoustics.