Mesopelagic Southern Ocean Prey and Predators (MESOPP) is a cooperation project funded under the European H2020-INT-INCO-2015 programme (Enhancing and focusing research and innovation cooperation with the Union’s key international partner countries) between Europe and Australia .
The underlying concept of MESOPP is the creation of a collaborative network and associated e-infrastructure (marine ecosystem information system) between European and Australian research teams/institutes sharing similar interests in the Southern Ocean and Antarctica, its marine ecosystem functioning and the rapid changes occurring with the climate warming and the exploitation of marine resources.
MESOPP will focus on the enhancement of collaborations by eliminating various obstacles in establishing a common methodology and a connected network of databases of acoustic data for the estimation of micronekton biomass and validation of models. It will also contribute to a better predictive understanding of the Southern Ocean based on furthering the knowledge base on key functional groups of micronekton and processes which determine ecosystem dynamics, including carbon cycle and distributions of large oceanic predators. it is expected that this project and associated implementation (science network and specification of an infrastructure) could constitute the nucleus of a larger international programme of acoustic monitoring and micronekton modelling to be integrated in the general framework of ocean observation following a roadmap that will be prepared during the project.
The Southern Ocean (here defined as the ocean south of 40°S) is a critically important part of the Earth system. It is one of the world’s most productive marine ecosystems and a key component of the global carbon cycle, providing a large sink for both heat and anthropogenic carbon dioxide. Oceanic measurements and modelling indicate that about one third of the global oceanic CO2 sink is located in the Southern Ocean, mainly in the subpolar region. The atmospheric CO2 penetrating water from the surface is used by phytoplankton through the photosynthesis, and the carbon is exported in the food web or the deep ocean.
About 70% of the CO2 concentration difference over the top 1000 m of the ocean is maintained by biological processes, known as the “biological pump”. Quantifying the biological pump is a prerequisite for developing accurate global carbon models and reliable impacts of climate change on ocean ecosystems. The mechanism goes through the knowledge on both active and passive (sinking) components. Active transport is due to vertical movements of animals, from zooplankton to mesopelagic micronekton organisms migrating daily, or seasonally, between the surface layer and the deep ocean.
Apart from changes in climate and environment, marine ecosystems are also facing increasing pressure from marine resource exploitation. After whales in the past and krill exploitation nowadays, exploitation of mesopelagic fishes resources in the Southern Ocean and more generally in the global ocean raised interest, being presented as a potential for “blue growth”. However, without a good knowledge of the dynamics and biomass of these species and the understanding of their role in the ecosystem to support the large diversity of predator species, the development of such exploitation could have dramatic impacts on the whole ecosystem. There is still a large research and monitoring effort required to estimate this marine biomass and its dynamics, and including these results in marine ecosystem models. A priority is also to develop routine in situ observations and monitoring of the world marine biomass to estimate dynamics and change in marine ecosystems.