Zusammenfassung
In the Southern Ocean, several zooplankton taxonomic groups, euphausiids, copepods,
salps and pteropods, are notable because of their biomass and abundance and their
roles in maintaining food webs and ecosystem structure and function, including the
provision of globally important ecosystem services. These groups are consumers of
microbes, primary and secondary producers, and are prey for fishes, cephalopods,
seabirds, and marine mammals. In providing the link between microbes, primary
production, and higher trophic levels these taxa influence energy flows, biological
production and biomass, biogeochemical cycles, carbon flux and food web interactions
thereby modulating the structure and functioning of ecosystems. Additionally, Antarctic
krill (Euphausia superba) and various fish species are harvested by international
fisheries. Global and local drivers of change are expected to affect the dynamics
of key zooplankton species, which may have potentially profound and wide-ranging
implications for Southern Ocean ecosystems and the services they provide. Here we
assess the current understanding of the dominant metazoan zooplankton within the
Southern Ocean, including Antarctic krill and other key euphausiid, copepod, salp and
pteropod species. We provide an overview of observed and potential future responses
of these taxa to a changing Southern Ocean and the functional relationships by
which drivers may impact them. To support future ecosystem assessments and
conservation and management strategies, we also identify priorities for Southern Ocean
zooplankton research.