CCAMLR

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.

The fourth year survey and observations of Dissostichus spp. in statistical subarea 48.2 on board the Ukrainian vessel SIMEIZ were conducted in accordance with the recommendations of the Scientific Committee and Commission. The fourth year survey design was slightly amended in comparison with the one of the second year and approved by WGs SAM, FSA and SC CCAMLR.  Obtained data will be used for the future biomass estimation of the target species and making decision for the future fishing on that fishing ground.

In the fishing season of 2018, three Ukrainian fishing vessels collected oceanographic data (salinity and temperature). The method of data collection is described. A preliminary analysis of the data was carried out.

During open discussions at the Third International Symposium on Krill (St Andrews, Scotland, June 2017) attended by representatives of the Association of Responsible Krill harvesting companies (ARK), the Marine Stewardship Council (MSC) and CCAMLR, it became apparent that no bycatch of Ice krill (Euphausia crystallorophias) had been reported from fishing vessels targeting Antarctic krill (E. superba). Furthermore there seemed to be little confidence amongst participants that under present observer practice any such bycatch would be detected – this despite the fact that fishers are obligated as a condition of their fishing permits to report all bycatch. Since the present-day Antarctic krill fishery operates in geographic areas that overlap with the known range of Ice krill, that Ice krill and Antarctic krill can occupy similar depths in the water column, and that both species are morphologically similar, the possibilities of bycatch and the failure to detect it cannot be dismissed. Here we analyse publicly-available aggregated decadal-scale krill catch data to evaluate the likelihood that Ice krill will have been included in the reported Antarctic krill catch. We conclude that the likelihood is effectively 100%. The MSC asserts that “bycatch and discards remain[ed] significant to ensuring sustainability. They are considered a waste of resources and contradictory to the overall concept of responsible fisheries” (https://improvements.msc.org/ database/discards; our emphasis). Stemming from this, the MSC now (as of April 2015) requires “fisheries to regularly review alternative mitigation measures to minimise mortalities of unwanted catch”. The krill fishery prosecuted by Aker Biomarine (a member of the Association of Responsible Krill harvesting companies; our emphasis) achieved MSC re-certification in August 2015 (https://www.msc.org/newsroom/news/ msc-labelled-aker-biomarine-krill-products-are-from-a-sustainable-and-well-managed-fishery), but it is not apparent if the probability of bycatch of Ice krill was considered for this re-certification. In the absence of any data, or clear statement, on Ice krill bycatch, it is difficult to reconcile the MSC’s statement (ibid.) that the Aker Biomarine “fishery remains excellent in its performance against MSC standards”. As part of the ongoing MSC assessment of the Deris S.A. – Pesca Chile Antarctic krill fishery (https://fisheries. msc.org/en/fisheries/deris-s.a.-pesca-chile-antarctic-krill-fishery/) and the scheduled re-assessment of Norway’s Aker Biomarine Antarctic krill fishery (https://fisheries.msc. org/en/fisheries/aker-biomarine-antarctic-krill/@@view; due before June 2020) we suggest that due consideration be given to the possibility of under-recording of bycatch of Ice krill in the Antarctic krill fishery, and to associated measures to address this situation.