Several studies have emphasized the variable abundance of Pygoscelid penguins from different colonies around Antarctica. In this study, the extinction risk of Adélie, Chinstrap and Gentoo penguins was evaluated in order to identify the most endangered colonies under present-day and future environmental scenarios. The extinction risk was estimated for twelve colonies from environmentally contrasting areas, such as the Antarctic Peninsula, Ross Sea and East Antarctica. We focused on the endogenous structure and the response of population dynamics of each colony to exogenous perturbations. The intraspecific competition appears as the most important endogenous factor in all colonies. In turn, the response to exogenous perturbations was rather idiosyncratic and dependant on the local conditions. Those colonies most vulnerable to climate change showed a strong dependency on sea ice extent during the winter, i.e. prior to the breeding season, which directly affects the carrying capacity of the area. The reduction of carrying capacity is mediated by a decrease in food availability and appears as key factor for the persistence of these populations. Based on these results, probabilities for extinction and quasi-extinction under different climate change scenarios were estimated. The most vulnerable Adélie penguin colonies are distributed on the Shetland Islands (Antarctic Peninsula) and at Syowa Station (Eastern Antarctic). The Subantarctic Gentoo penguin colony on Marion Island appears particularly vulnerable and governed by macro-scale environmental variability represented by the Southern Annular Mode index (SAM).

The sub-Antarctic region -here considered between the sub-Antarctic Front and the southern boundary of the Antarctic Circumpolar Current (ACC) -falls under many distinct jurisdictions, including Exclusive Economic Zones (EEZs) of several countries, as well as the areas of competence of several international bodies as the SEAFO, SIOFA and CCAMLR. However, in oceanographic terms, these zones appear mostly as a continuum, due to the connecting effectof the ACC. In this paper we review some techniques which have been developed recently in order to trace connectivity and dispersal patterns induced by the horizontal transport. These are satellite-based Lagrangian methods, which predict remarkably well the extent of phytoplanktonic blooms occurring for hundreds of kilometres in the wake of nutrient sources like islands, seamounts, and hydrothermal vents. These quantitative methods can be applied as well to areas under and beyond national jurisdictions. As an example, we show here the cross-boundary dispersal patterns of the water within and beyond the EEZs in the sub-Antarctic. These patterns inform on the incoming and outcoming pathways of tracers transported in the upper layer, like fish larvae and possible pollutants. The high connection of the physical and biological processes and the cross-boundary physical linkage suggests a geographically integrated evaluation of the sub-Antarctic region.

The purpose of this "paper" is to present a research project in progress on the physiology of Antarctic krill, with a focus on the response to environmental temperature variations. This study first focused on the study of heat shock proteins (HSP) and the comparative aspect quickly became essential for a better understanding of the mechanisms involved in relation to the environment. On the basis of this observation, this comparative approach has become the basis of the project and should soon focus on data from at least 25 different euphausiid species harvested in the Antarctic, Arctic and a latitudinal gradient stretching from the tropical environment to the waters of the Antarctic Polar Front. This ecophysiological study is as global as possible and combines transcriptomic (currently 17 transcriptomes are already available), metabolomic and lipidomic approach in the frame of French-Taiwanese and French-Chilean collaboration.

At WG-SM-18, the Secretariat presented the development and progress made on a Project List web database to support Research and Monitoring Plans (RMPs) for individual Marine Protected Areas (MPA), as recommended by SC-CAMLR-XXXVI. This paper reports on the updates made to the data structure model for the CCAMLR MPA Information Repository (CMIR), based on feedback received at WG-SM-18, through intersessional consultation, and following a review of the proposed RMPs from each MPA. The updated data structure model seeks to harmonise general principles across all of the RMPs.

Krill length data collected from fishery-dependent and fishery-independent data sources were analysed for trends in population structure. Krill length data collected by the Scheme of Scientific Observation (SISO) and the CCAMLR Ecosystem Monitoring Program (CEMP) from 2008 to 2019 in the Bransfield Strait were compared. Differences in mean lengths and length-frequencies were apparent, however both data sources appeared to be tracking similar processes. CEMP data revealed patterns in population structure consistent with previous studies, and may provide a more appropriate source for measuring shifts in population structure and recruitment. Analysis demonstrates the importance of using long-term data collected by different sources to gain a complete understanding of trends in krill population structure and dynamics for use in fisheries management.

This paper outlines the objectives, survey and analytical procedures and work schedule of a new non-lethal research program on whales and the ecosystem in the Indo-Pacific region of the Antarctic (JASS-A= Japanese Abundance and Stock structure Surveys in the Antarctic). The main research objectives are i) the study of the abundance and abundance trends of Antarctic minke and other large whale species, and ii) the study of the distribution, movement and stock structure of Antarctic minke and other large whale species. JASS-A also has several secondary research objectives related to oceanographic, marine debris and whale biology. The research program will be based on systematic sighting surveys utilizing the Line Transect Method, to be conducted alternatively in IWC Areas III, IV, V and VI by one or two specialized vessels, during a tentative period of eight austral summer seasons. Analyses related to main and secondary objectives will be conducted based on new as well previous data collected by JARPA/JARPAII and NEWREP-A in the same research area. Therefore the analyses under each of the objectives will be based on large and consistent data sets. The survey plan for the 2019/20 austral summer season is presented as an appendix to this document.

The main purpose of this study was to investigate the distribution and areas of mixing of two stocks of the humpback whale, a krill predator, in the Indo-Pacific region of the Antarctic. These were breeding Stock ‘D’ off Western Australia and breeding Stock ‘E1’ off Eastern Australia. Both stocks have shown sign of recovery after heavy commercial exploitation in the last century. Information on distribution and areas of mixing in the Antarctic feeding grounds is essential to assist the interpretation of abundance estimates. Published mitochondrial DNA (mtDNA) sequences were available for Western Australian (n= 185) and Eastern Australian (n= 104) whales. These were compared with sequences of humpback whales in the Antarctic feeding grounds for Areas IIIE (35°-70°E, n= 95), IVW (70°-100°E, n= 140), IVE (100°-130°E, n=90), VW (130°-160°E, n= 69), VE (160°E-170°W, n=85) and VI (170°-120°W, n=64). In addition, the Antarctic samples were analyzed with a set of eleven microsatellite DNA loci (independent nuclear DNA marker). The genetic analyses were based on biopsy samples. Results of the combined analyses suggested the following: i) Western Australian whales distribute mainly in Areas IV, and probably mix with a different stock in Area IIIE; ii) Western Australian whales do not distribute in Areas V and VI, at least in substantial numbers; iii) Eastern Australian whales distribute mainly in Area VW, and probably mix with a different stock in Area VE; Area VI is occupied by a different stock. This information on distribution and areas of mixing should be used in the interpretation of the abundance estimates of the Western and Eastern Australian stocks in the Antarctic, which has been based on the boundaries of IWC Management Areas. Several additional analyses were suggested to refine the information on pattern of distribution and mixing of humpback whales stocks suggested in this study.

We provide an analysis of zooplankton distributions in the circumpolar Southern Ocean based on samples collected by the international Southern Ocean Continuous Plankton Recorder Survey (SO-CPR) between 1991 and 2018. We analysed SO-CPR measurements in relation to satellite and oceanographic observations over the period 1997–2018. These environmental data were: phytoplankton biomass, primary productivity, sea-surface temperature (SST), mixed layer depth, sea ice and the spatial gradient of SST (as an indicator of ocean fronts). Boosted Regression Tree models were used to investigate relationships between the abundances of key groups of zooplankton, occurrence of characteristic zooplankton communities, and environmental conditions. Analysis is presented on the environmental suitability for six broad zooplankton groups: Copepoda, Euphausiidae (numerically dominated in SO-CPR data by Thysanoessa macrura), Foraminifera, Fritillaria spp., Oithona similis and pteropods. Trend analysis suggests that the environmental suitability for copepods, Foraminifera, and Fritillaria spp. may lead to increasing abundances at between 0.59–0.83% per year averaged across the Southern Ocean, and with much higher rates of increase in some regions. In contrast, the environmental suitability for pteropods is predicted to be decreasing in the Ross Sea region. Eight characteristic zooplankton communities were identified based on multivariate cluster analysis. The analysis suggests that the areal extent of the northern (Subantarctic) communities have not changed or decreased in area between 1998 and 2018, whereas the main Polar Frontal communities have expanded, and the area occupied by the southernmost (sea-ice) zooplankton community has decreased in area. These analyses are relevant to evaluating the conservation value of the Ross Sea region Marine Protected Area against its specific objectives.

In 2019, the annual IMR regional krill monitoring survey off the South Orkneys was conducted by RV Kronprins Haakon as part of the Scotia Sea large scale krill monitoring effort. To allow for comparison with previous survey years and provide some context for the large scale survey estimate, we here present the results from the 2019 regional survey processed and analysed in the same way as the annual surveys from 2011 to 2018. The distribution was similar to previous years with most krill along the shelf edge north of the Islands. Also the krill areal density measured on the 120 kHz of 69.87 g/m² was very close to the long term average. Sampling variance, however, expressed as coefficient of variation was the second lowest on record, indicating a less patchy krill distribution than a typical year. 

A collection of published papers about population variability of several biological parameters and factors affecting penguins biology along the Antarctic Peninsula is presented in order to contribute to the general knowledge of penguin biological variation, to generate a data baseline in the context of environmental changes such as climate change and human activity and to support the proposal of the Western Antarctic Peninsula protected marine area. The results show higher levels of immunological parameters, higher abundance of ectoparasites and a higher stress in northern populations. Contaminant levels and genotoxic damage are associated with human activity mostly located in the northern populations as well.