Special Issue on Mesopelagic Fish
African Journal of Marine Science Volume 48 Issue 3 is a special issue titled "Mesopelagic fish in the Benguela Current ecosystem and Indian Ocean: environmental influences on communities, trophic interactions and emerging fisheries".
Guest Edited by Mark Gibbons and Anne Gro Vea Salvanes, the special issue introduces the results of seven studies focused on mesopelagic resources in the southeastern Atlantic and Indian Ocean, which collectively serve to improve our understanding of fish biomass, distributions and ecology in the ‘twilight’ zone of the region’s oceans.
Most of the studies are products of support by the EAF-Nansen Programme, South Africa’s National Research Foundation, and the Research Council of Norway showcasing the benefits of collaboration.
Mesopelagic fish are species that inhabit depths of ~200–1 000 m in the open ocean where light levels are too low for photosynthesis yet sufficient for visually feeding species. They form a central trophic link in open ocean ecosystems, transferring energy from zooplankton to higher-level predators and many undertake massive diel vertical migrations to the surface to feed, which drives vertical fluxes of carbon and nutrients.
Although mesopelagic fish have been well studied in the northeastern Atlantic, including in the fjords of western Norway they are relatively under studied elsewhere in the world.
“We introduce here the results of seven studies focused on mesopelagic resources in the southeastern Atlantic and Indian Ocean, which collectively serve to improve our understanding of fish biomass, distributions and ecology in the ‘twilight’ zone of the region’s oceans,”
said the Guest Editors in their overview of the Special Issue.
Despite the importance of mesopelagic micronekton which includes small midwater fishes, cephalopods and crustaceans like krill, aspects of their ecology, distribution and biomass remain poorly resolved, especially in the central and southeastern Atlantic Ocean and Indian Ocean.
The seven studies presented in this Special Issue span biological, ecological, environmental, technological and applied dimensions of mesopelagic science in the region.
Together, these studies trace how the characteristics of individual fish could scale up to the structure of populations and communities, how these communities interact with their physical and biogeochemical environment, how multifrequency hydroacoustic tools can be used to quantify them, and how these insights could inform potential fisheries.
The special issue can be found here.