Sonophore enables autonomous observation of micronekton communities in the ocean twilight zone

The future productivity of pelagic ecosystems and fisheries globally remains uncertain due to a lack of data on mid-trophic mesopelagic micronekton communities. Here, we demonstrate that integrating readily available autonomous profiling floats with autonomous echosounders enables vertically resolved abundance estimates of mesopelagic micronekton communities, a platform we are naming the "Sonophore". This successful demonstration is a first step towards addressing critical data gaps identified by fisheries management, earth system and ecosystem modelling communities. With planned engineering enhancements, this platform offers a scalable solution for rapid, cost-effective, year-round monitoring of the planet's largest vertebrate (but deeply uncertain) biomass. The platform is specifically designed for long-term monitoring of remote and spatially extensive oceanic habitats of the global ocean, without the need for large, expensive research vessels.