Benthic biodiversity in the South Orkney Islands Southern Shelf Marine Protected Area

The South Orkney Islands Southern Shelf (SOISS) Marine Protected Area (MPA) was the first MPA to be designated entirely within the high seas and is managed under the Commission for the Conservation of Antarctic Marine Living Resources (CCAMLR). To assist with research and monitoring of the MPA, an international expedition (‘SO-AntEco’) was undertaken in the austral summer of 2016 to contribute towards a better understanding of selected benthic habitats within the region. The benthic assemblages of the SOISS MPA region were found to be strongly correlated with the texture of the seafloor, where hard substrates hosted a greater number of individuals, taxa and biomass with a dominance of filter feeding vulnerable marine ecosystem (VME) taxa, and soft sediments were dominated mostly by deposit feeders. Substantial differences in the abundance of VME taxa were found between sampling gears (shallow underwater camera system and Agassiz trawl). We conclude that camera systems may be more suitable for VME assessments, but additional trawling is advisable for collecting all faunal types and for higher taxonomic resolution. The designation of VME locations based purely on large scale geomorphic classification is not advisable, due to small scale variation in substrate and other local physical influences

Benthic megafauna of the western Clarion-Clipperton Zone, Pacific Ocean

There is a growing interest in the exploitation of deep-sea mineral deposits, particularly on the abyssal seafloor of the central Pacific Clarion-Clipperton Zone (CCZ), which is rich in polymetallic nodules. In order to effectively manage potential exploitation activities, a thorough understanding of the biodiversity, community structure, species ranges, connectivity, and ecosystem functions across a range of scales is needed. The benthic megafauna plays an important role in the functioning of deep-sea ecosystems and represents an important component of the biodiversity. While megafaunal surveys using video and still images have provided insight into CCZ biodiversity, the collection of faunal samples is needed to confirm species identifications to accurately estimate species richness and species ranges, but faunal collections are very rarely carried out. Using a Remotely Operated Vehicle, 55 specimens of benthic megafauna were collected from seamounts and abyssal plains in three Areas of Particular Environmental Interest (APEI 1, APEI 4, and APEI 7) at 3100–5100 m depth in the western CCZ. Using both morphological and molecular evidence, 48 different morphotypes belonging to five phyla were found, only nine referrable to known species, and 39 species potentially new to science. This work highlights the need for detailed taxonomic studies incorporating genetic data, not only within the CCZ, but in other bathyal, abyssal, and hadal regions, as representative genetic reference libraries that could facilitate the generation of species inventories.</jats:p

Patterns, processes and vulnerability of Southern Ocean benthos: a decadal leap in knowledge and understanding

In the Southern Ocean, that is areas south of the Polar Front, long-term oceanographic cooling, geographic separation, development of isolating current and wind systems, tectonic drift and fluctuation of ice sheets amongst others have resulted in a highly endemic benthic fauna, which is generally adapted to the long-lasting, relatively stable environmental conditions. The Southern Ocean benthic ecosystem has been subject to minimal direct anthropogenic impact (compared to elsewhere) and thus presents unique opportunities to study biodiversity and its responses to environmental change. Since the beginning of the century, research under the Census of Marine Life and International Polar Year initiatives, as well as Scientific Committee of Antarctic Research biology programmes, have considerably advanced our understanding of the Southern Ocean benthos. In this paper, we evaluate recent progress in Southern Ocean benthic research and identify priorities for future research. Intense efforts to sample and describe the benthic fauna, coupled with coordination of information in global databases, have greatly enhanced understanding of the biodiversity and biogeography of the region. Some habitats, such as chemosynthetic systems, have been sampled for the first time, while application of new technologies and methods are yielding new insights into ecosystem structure and function. These advances have also highlighted important research gaps, notably the likely consequences of climate change. In a time of potentially pivotal environmental change, one of the greatest challenges is to balance conservation with increasing demands on the Southern Ocean's natural resources and services. In this context, the characterization of Southern Ocean biodiversity is an urgent priority requiring timely and accurate species identifications, application of standardized sampling and reporting procedures, as well as cooperation between disciplines and nations. © 2013 Springer-Verlag Berlin Heidelberg.0SCOPUS: re.jinfo:eu-repo/semantics/publishe