In order to understand and mitigate for the potential impacts of anthropogenic disturbance on marine predators it is fundamental to gain insight into the drivers behind the temporal variation in their current distribution. With this in mind, we used Platform Terminal Transmitter (PTT) devices to track Adélie and chinstrap penguins breeding on the South Orkney Islands during the pre-moult phase of the annual cycle. We show that Adélie penguins have an affinity to forage and moult on sea-ice, and that chinstraps remain over the shallower shelf waters during pre-moult, and return to the colony to moult. However, habitat models aimed to predict the preferred foraging habitats of penguins during pre-moult had low predictive power. This indicates that predictive models may be insufficient to understand the distribution and foraging behaviour of penguins during certain stages of the life-cycle, and that collecting empirical data from individual colonies or archipelagos is vital if we are to understand the potential implications of future climate warming, or indeed with the overlap with potentially competing fisheries.

The present document is an update of document EMM-16/52, presenting refine analysis of the krill fishing hotspots and a description of the daily CPUE pattern for the krill fishery. This paper has now been accepted for publication in Fisheries Research.

Results identified several fishing hotspots (FHs), where the fleet took 48 to 57% of the seasonal catch, and are relatively persistent seasonality (2-6 months) with high catch densities (2.2-30.3 ton∙km-2). Within these FHs, we observed that the spatial distribution of the fleet is modulated by a dome-shaped daily CPUE. When CPUE decreased, the fleet moved towards contiguous zones, achieving new maximum CPUE values. Such displacements occurred every 4-17 days and, according to FH persistence and sea ice conditions, previously exploited zones were revisited.

This paper provides an update on the joint UK-Norway MMAK project, funded by the Antarctic Wildlife Research Fund, to improve current understanding of the regional and local-scale processes that influence the distribution of Antarctic krill in CCAMLR Area 48, focussing in particular on the South Orkney Islands region.  MMAK uses modelling studies at varying spatial and temporal resolutions to investigate the impact of physical and behavioural processes on the distribution of krill in this area, at scales relevant to the krill fishery and predators.  Preliminary analysis of a 20-year time series of simulated transport to the South Orkneys region demonstrates spatial and temporal variability in input and transfer to the wider Scotia Sea.  Results suggest that resolving the interaction of krill with sea ice is critical for determining the pathways and timescales of transport into and out of the region. Links between transport and large-scale climatic indices are now being explored and processes at a finer resolution are being investigated, which will include examination of the role of tides in determining on-shelf retention and transfer.

Most seafloor communities at depths below the photosynthesis zone rely on food that sinks through the water column. However, the nature and strength of this pelagic–benthic coupling and its influence on the structure and diversity of seafloor communities is unclear, especially around Antarctica where ecological data are sparse. Here we show that the strength of pelagic–benthic coupling along the East Antarctic shelf depends on both physical processes and the types of benthic organisms considered. In an approach based on modelling food availability, we combine remotely sensed sea-surface chlorophyll-a, a regional ocean model and diatom abundances from sediment grabs with particle tracking and show that fluctuating seabed currents are crucial in the redistribution of surface productivity at the seafloor. The estimated availability of suspended food near the seafloor correlates strongly with the abundance of benthic suspension feeders, while the deposition of food particles correlates with decreasing suspension feeder richness and more abundant deposit feeders. The modelling framework, which can be modified for other regions, has broad applications in conservation and management, as it enables spatial predictions of key components of seafloor biodiversity over vast regions around Antarctica.

Quantifying biological assemblages and their environment is a fundamental, yet statistically challenging task in conservation ecology. Here we use a recently-developed approach called Regions of Common Profile (RCP) to quantify and map the distribution of demersal fish assemblages in an ecologically significant region of the Southern Ocean to a) gain ecological and management insights and b) evaluate the utility of the new method for ecoregionalisation.

The RCP approach is a multi-species, model-based approach that can overcome many limitations of traditional distance-based approaches.  It simultaneously groups sites with a similar composition of species and describes the patterns of variation in assemblages using environmental data, allowing the prediction of assemblages across the study region. We apply RCP to a unique dataset of demersal fish occurrences across the northern Kerguelen Plateau to model and map the distribution of assemblages and examine the representativeness of the Heard Island and McDonald Island marine reserve.      

We demonstrate that the RCP approach allows a direct and quantitative interpretation of the composition of assemblages as well as their environment. Further, the model reasonably predicts the occurrence of individual species across the plateau as well as the species composition of sites.  We distinguish and map seven assemblages defined by depth, surface temperature and chlorophyll-a. Shallow-water assemblages contain a high proportion of endemic species, while deep-water assemblages contain more cosmopolitan species. With the exception of one deep-water assemblage, assemblages were well represented within the current Heard and McDonald Islands marine reserve.

The RCP is a valuable tool for classifying biological regions with a range of ecological and conservation management applications. Our results extend current ecological and biogeographic knowledge for the Northern Kerguelen Plateau and maps of the distribution of assemblages will be useful for ongoing spatial management.

This paper represents the annual report of a multi-member longline survey on Antarctic toothfish (Dissostichus mawsoni) at Statistical Subarea 48.6 for 2016/17 fishing season by Japan and South Africa. The data set, C2 and Oｂserver data, was provided by the CCAMLR Secretariat on the 20th of April, 2018. In this paper, the data set during last fishing season (2016/17) was used for reporting the quantity of data, samples collected, and results of quick analysis as a progress toward research milestones.

This paper represents the annual report of a multi-member longline survey on Patagonian toothfish (Dissostichus eleginoides) at Division 58.4.4b in 2016/17 fishing season by France and Japan. The data set, C2 and Observer data, was provided by the CCAMLR Secretariat on the 20th April 2018 (30 May, 2018 for September to November French cruise). In this paper, the data set during last fishing season (2016/17) was used for reporting the quantity of data, samples collected, and results of quick analysis as a progress toward research millstones.

The document presents the experience of the age determination of toothfish of the genus Dissostichus by recording structures (otoliths). Sampling processing is carried out on the basis of annual data collected in the CCAMLR Convention Area. The equipment used, the procedure for processing and reading age are described. The achieved volumes and results are given. And also the problems that arose and the ways to solve them.