Description: The polar seas are generally ice-covered waters with highly seasonal weather conditions, temperature, formation and extent of sea ice. To date, more than 8,000 marine species are estimated to occur in these waters (5,782–Arctic;〉 8,200–Antarctic). A collaboration with the Alfred-Wegener-Institut resulted in a preliminary list of marine species in the polar seas (7,710 species), collated from published documentation and made available via FishBase and SeaLifeBase. This list includes 533 species of bony fishes, 10 sharks, 17 rays, 208 vertebrates (whales, dolphins and sea birds), and at least 6,816 invertebrates and 114 plant species. This report includes the polar sea species list, their marine ecoregions, and an overview of available data on ecology, life history, and population dynamics.

Description: The recent identification of the bio-duck call as Antarctic minke whale (AMW) vocalization allows the use of passive acoustic monitoring to retrospectively investigate year-round spatial-temporal patterns in minke whale occurrence in ice-covered areas. Here, we present an analysis of AMW occurrence patterns based on a 9-year passive acoustic dataset (2008–2016) from 21 locations throughout the Atlantic sector of the Southern Ocean (Weddell Sea). AMWs were detected acoustically at all mooring locations from May to December, with the highest presence between August and November (bio-duck calls present at more than 80% of days). At the southernmost recording locations, the bio-duck call was present up to 10 months of the year. Substantial inter-annual variation in the seasonality of vocal activity correlated to variation in local ice concentration. Our analysis indicates that part of the AMW population stays in the Weddell Sea during austral winter. The period with the highest acoustic presence in the Weddell Sea (September–October) coincides with the timing of the breeding season of AMW in lower latitudes. The bio-duck call could therefore play a role in mating, although other behavioural functions of the call cannot be excluded to date.

Description: Amiantis purpurata is a common warm-temperate water bivalve species distributed from southern Brazil to northern Patagonia, Argentina, which has a rich and well preserved fossil record in the San Matias Gulf (SMG) dating back to the late Quaternary. This study aims to establish A. purpurata shells as a new palaeoarchive of past marine conditions in South America. We compared the stable oxygen and carbon profiles (818O,heu; 813CS hcii) of eleven specimens of A. purpurata from different geological times (modem, Late Holocene and interglacial Late Pleistocene), and additionally present in situ oxygen isotope values of seawater within SMG (S,8Owatcr). Using both sets of information, we calculated and reconstructed palaeowater temperatures for the Late Holocene and compared them to modem water temperatures. Our findings indicate that A. purpurata records past environmental parameters such as water temperatures on a seasonal scale and can therefore be considered a suitable candidate for future palaeoenvironmental reconstructions in Northern Patagonia. This study is the first step towards further stable isotope analyses on fossil A. purpurata shells, which will show whether and if so, to what extent, important global climate events such as the Neoglacial (Early Holocene), the Hypsithermal (Middle Holocene) and the Little Ice Age (Late Holocene) occurred in South America.

Description: Currently, almost 8% of the world’s oceans are designated marine protected areas (MPAs), the majority of which are relatively small and under national jurisdiction. Several initiatives are presently underway in international waters to establish large-scale MPAs, such as for the Southern Ocean under the Commission for the Conservation of Antarctic Marine Living Resources (CCAMLR). By reviewing the MPA initiative in the Weddell Sea (WSMPA), we aim to guide through the planning steps involved in developing an MPA in the high seas of the Southern Ocean in the context of an international organisation, i.e. CCAMLR. We focus also on the associated sciencepolicy discussion process. To this end, we examine the WSMPA roadmap retrospectively from its beginning in 2013 until today. We discuss the individual planning steps and how these have been designed in detail. Throughout, we show that the planning of the WSMPA was based on a collaborative, science-based process that exemplified best practice in applied science. Lastly, we also provide an outlook on the current situation regarding the establishment of CCAMLR MPAs and point out that scientific best practice may not be sufficient to achieve the consensus and political drive ultimately required for the designation of MPAs in the Southern Ocean.

Description: The Southern Ocean may contribute a considerable amount to the proposed global network of marine protected areas (MPAs) that should cover about 10 % of the world’s oceans in 2020. In the Antarctic, the Commission for the Conservation of Antarctic Marine Living Resources (CCAMLR) is responsible for this task, and currently Germany leads a corresponding scientific evaluation of the wider Weddell Sea region. Compared to other marine regions within the Southern Ocean, the Weddell Sea is exceptionally well investigated. A tremendous amount of data and information has been produced over the last 4 decades. Here, we give a systematic overview of all data sources collected in the context of the Weddell Sea MPA planning process. The compilation of data sources is comprised of data produced by scientists and institutions from more than 20 countries that were either available within our institutes, downloaded via data portals or transcribed from the literature. It is the first compilation for this area that includes abiotic data, such as bathymetry and sea ice, and ecological data from zooplankton, zoobenthos, fish, birds and marine mammals. All data layer products based on this huge compilation of environmental and ecological data are available from the data publisher PANGAEA via the six persistent identifiers at https://doi.org/10.1594/PANGAEA.899595 (Pehlke and Teschke, 2019), https://doi.org/10.1594/PANGAEA.899667 (Teschke et al., 2019a), https://doi.org/10.1594/PANGAEA.899645 (Teschke et al., 2019b), https://doi.org/10.1594/PANGAEA.899591 (Teschke et al., 2019c), https://doi.org/10.1594/PANGAEA.899520 (Pehlke et al., 2019a) and https://doi.org/10.1594/PANGAEA.899619 (Pehlke et al., 2019b). This compilation of data sources including the final data layer products will serve future research and monitoring well beyond the current MPA development process.