Large mesopelagic fish biomass in the Southern Ocean resolved by acoustic properties.

ABSTRACT: The oceanic mesopelagic zone, 200-1000 m below sea level, holds abundant small fishes that play central roles in ecosystem function. Global mesopelagic fish biomass estimates are increasingly derived using active acoustics, where echosounder-generated signals are emitted, reflected by pelagic organisms and detected by transducers on vessels. Previous studies have interpreted a ubiquitous decline in acoustic reflectance towards the Antarctic continent as a reduction in mesopelagic fish biomass. Here, we use empirical data to estimate species-specific acoustic target strength for the dominant mesopelagic fish of the Scotia Sea in the Southern Ocean. We use these data, alongside estimates of fish relative abundance from net surveys, to interpret signals received in acoustic surveys and calcul

SUBMITTER: Dornan T 

PROVIDER: S-EPMC8790350 | biostudies-literature | 2022 Jan

REPOSITORIES: biostudies-literature