Valuing the Treasures of the Twilight Zone: mesopelagic species and their delivery of biodiversity, climate, food and other services

Environmental Defense Fund

Saturday, December 9th, 2023
09:00 - 10:00

The extremely abundant species of the mesopelagic realm are one of the ocean’s most undervalued treasures. Comprising an astonishing array of biodiversity that may represent 95% of global marine biomass, they play a critical role in ecosystem functioning and are viewed as a potential replacement for dwindling sources of fishmeal and fish oil. However, their potential to help address climate change via movement of fixed carbon into the depths has only recently become a focus of ocean research – there remains much we need to learn to ensure a precautionary approach that includes climate dynamics is fully incorporated before considering any new targeting of these species for industrial exploitation. We must fully evaluate the benefits they can provide humans and nature both in and out of the water and use this information to set up regulatory frameworks to help guide how the world’s nations value and use mesopelagic species to balance ecological and human needs. This panel will discuss what science suggests are the greatest benefits of mesopelagic species to the planet, the role of management in conserving these benefits, and ways to ensure we make the most of this resource.


  • Cymie R. Payne, Rutgers University
  • Dr. Kilaparti Ramakrishna, Director of Marine Policy Center and Senior Advisor to the President on Ocean and Climate Policy, Woods Hole Oceanographic Institution
  • Dr. Mariano Gutiérrez, Humboldt Institute of Marine Research and Aquaculture (IHMA)
  • Peter Thomson, UN Secretary-General’s Special Envoy for the Ocean