Mapping the global prey-field: Combining acoustics, optics and net samples to reduce uncertainty in estimates of mesopelagic biomass

Mesopelagic (200–1000 m depth zone) biomass largely comprises zooplankton, jellyfish, squid and fish. Part of this biomass actively migrates between the surface and the mesopelagic zone on a daily basis, playing an important role in global biogeochemical cycling. When observed using echosounders, aggregated components of this community (largely made up of fish and siphonophores) are known as Deep Scattering Layers (DSLs). DSLs have been used to...