South Africa and Japan revised the next season’s (2017/18) research plan in Subarea 48.6 using the latest CCAMLR C2 and Observer data, following the recommendations and notification from WG-SAM meeting in 2017 (e.g., WG-SAM-17 report, paragraph 4.4, 4.10, and 4.18, 2017) and data extracts provided by the CCAMLR Secretariat on the 27th of July, 2017 were used.

The estimated median stock sizes in research blocks 48.6_2E (southeast part of 48.6_2), 48.6_3, and 48.6_4 are 4864.30, 3132.55, and 8044.33 tonnes, respectively, when applying the Chapman method. Chapman method considers tags that were released in the most recent year as effective for the biomass estimation, except for 48.6_4 which considered the last three years when estimating biomass. The estimated median stock sizes in blocks 48.6_2W, 48.6_2E, 48.6_3, and 48.6_4 were 189.56, 306.31, 125.05, and 969.14 tonnes, respectively, when CPUE by sea bed area methods are used considering the relevant information of reference area (recent median CPUE, estimated biomass and updated area size) recommended in the WG-SAM-16/18 Rev.1.

We propose to continue the current research operation in Subarea 48.6 for the next fishing season with the same survey design. 

Following the note by the Working Group in paragraph 4.21 in WG-SAM-17 report on the ice concentration analysis by Namba et al. (WG-SAM-17/10), the further analyses for the ice concentration was conducted to investigate correlations between sea-ice coverage and wider global weather phenomena such as El Niño/El Niño Southern Oscillation or rising temperatures/increased variability in the sea surface temperature (SST) anomaly (variance from average) of ERDDAP of NOAA.

Stomach contents of the Antarctic toothfish, Dissostichus mawsoni, collected from Subareas 58.4 and 88.3 were analyzed using next generation sequencing (NGS) technology. After processing the raw reads generated by the MiSeq platform, a total of 131,233 contigs (130 operational taxonomic units [OTUs]) were obtained from 163 individuals in subarea 58.4, and 75,961 contigs (105 OTUs) from 164 fish in subarea 88.3. At 98 % sequence identity, species names were assigned to most OTUs in this study, indicating the quality of the DNA barcode database for the Antarctic Ocean was sufficient for molecular analysis, especially for fish species. A total of 19 species was identified from the stomach of D. mawsoni in this study, which included 14 fish species and 5 mollusks. More than 90 % of contigs belonged to fish species, supporting the postulate that the major prey of D. mawsoni are fish. Two fish species, Macrourus whitsoni and Chionobathyscus dewitti, were the most important prey items (a finding similar to that of previous studies). We also obtained genotypes of prey items by NGS analysis, identifying an additional 17 representative haplotypes in this study. Comparison with three previous morphological studies and the NGS-based molecular identification in this study extended our knowledge regarding the prey of D. mawsoni, which previously was not possible. These results suggested that NGS-based diet studies are possible, if several current technical limitations, including the quality of the barcode database or the development of precise molecular quantification techniques to link them with morphological values, are overcome. To achieve this, additional studies should be conducted on various marine organisms.

In the present study, the concentrations of total mercury in different organs of the Antarctic toothfish (Dissostichus mawsoni) collected from CCAMLR research blocks in Subarea 88.3 and Division 58.4.1 off the coast of Antarctica were determined. The results revealed total mercury concentrations of 0.165 ± 0.095 mg/kg (0.023–0.454 mg/kg) in the Antarctic toothfish. In fish muscle, methylmercury accounted for approximately 40% of the total mercury. In a comparison analysis, muscle and liver tended to bioaccumulate the highest levels of total mercury, and both total mercury and methylmercury contents showed correlations with fish length and weight. Compared with international guidelines, fish contained 2.5–6.4% and 4.0–10.3% of the provisional tolerable weekly intake for total mercury recommended by the Joint FAO/WHO Expert Committee on Food Additives and the tolerable weekly intake for methylmercury proposed by the European Food Safety Authority, respectively. These results suggest that consumption of the Antarctic toothfish presents no health risk to humans.

This report summarises fishing catch and effort in the Ross Sea region (Subarea 88.1 and SSRUs 882AB) together with biological characteristics of the catch of Antarctic toothfish through the 2017 season. In 2017, sea ice constraints were minimal and catch rates were the second highest on record, resulting in the shortest season to since the fishery started.

Median and 90%ile scaled lengths show no trend on the Shelf, Slope or North. Age frequencies show no uniform trend and are probably driven by location of fishing. The strongest time trend in the data is the change in the sex ratio over time in all three locations.

The catch limits for macrourid and skates are dictated by CM 41-09. Because the areas open to fishing will change in 2018, with the implementation of the Ross Sea region Marine Protected Area (CM 91-05), we recommend catch limit for bycatch species for the North, Slope and SRZ areas based on methods used to set those limits in the past.

The Southern Ocean Observing System (SOOS) Executive Committee requests that the Scientific Committee consider a proposal to hold a joint two-day workshop between representatives of SOOS and SC-CAMLR to consider mechanisms for communication, collaboration and co-operation between SOOS and SC-CAMLR.  SOOS was established in 2011 and has been communicating with the Scientific Committee since that time (see this year’s report in SC-CAMLR-XXXVI/BG/14).  Last year, SOOS was recognised by the Scientific Committee as having an important role in a number of areas of its work, including ecosystem monitoring and observation (SC-CAMLR-XXXV, paragraph 3.24; SC-CAMLR-XXXV-Annex 6, paragraphs 2.83, 2.84 and 2.94), spatial management of impacts on the Antarctic ecosystem (SC-CAMLR-XXXV, paragraph 5.7), climate change (SC-CAMLR-XXXV, paragraphs 8.3-8.4, 8.23-8.24) and data management (SC-CAMLR-XXXV, paragraph 14.4).  The report from SOOS this year (BG/14) indicates many activities of interest to SC-CAMLR, particularly the regional and capability working groups and the development of three tools that facilitate collaborations and data discovery. Given the many useful interactions that could be of benefit to both SC-CAMLR and SOOS, the Executive Committee of SOOS wishes to establish a dialogue with SC-CAMLR on how these interactions could be most easily achieved.  The proposed workshop aims to identify relevant mechanisms for achieving this.

This paper presents an update on the SCAR Antarctic Climate Change and the Environment Report, providing an overview of recent science. The update is not meant to be read as a synthesis report, but as a perspective on recent scientific advances. 

SCAR is an interdisciplinary body of the International Council for Science (ICSU), and currently includes 43 member countries and nine ICSU unions. SCAR is charged with initiating, developing and coordinating high quality international scientific research in the Antarctic region (including the Southern Ocean).

SCAR’s Mission is to advance Antarctic research, including observations from Antarctica, and to promote scientific knowledge, understanding and education on any aspect of the Antarctic region and its role in the Earth System. SCAR also provides independent and objective scientific advice and information to the Antarctic Treaty System and other bodies and facilitates the international exchange of Antarctic information within the scientific community.

Here SCAR reports on recent CCAMLR engagement, recent scientific research of relevance to SC-CAMLR, and forthcoming SCAR activities of mutual interest.

To ensure that transshipment does not provide a mechanism for toothfish harvested by  illegal, unreported and unregulated (IUU) fishing activities to enter commerce, as well as to address compliance issues discussed in SCIC, CCAMLR considered proposed revisions to existing measures to improve the monitoring and control of transshipments in 2014^[1], 2015^[2], and 2016^[3]. Despite robust consideration, no consensus was reached on these proposals. This paper draws Members’ attention to the new work on transshipment being carried out by the United Nations Food and Agriculture Organization (FAO) following on a recommendation from the Committee on Fisheries (COFI). The report by the FAO on this issue is expected to provide CCAMLR members with a strong resource to help address current gaps in the monitoring of transshipments.  The United States looks forward to reviewing the report’s findings and, with due consideration of the relevant recommendations from the second performance review (CCAMLR-XXXVI/01, paragraphs 54 and 55), working with other Members during the intersessional period on a proposal for consideration at CCAMLR XXXVII. Improving the monitoring and control of transshipments is critical to the prevention of support or concealment of IUU fishing and to improving CCAMLR’s understanding of transshipment activities involving Antarctic marine living resources harvested inside the Convention Area.

[1] SCIC 2014: the United States presented draft revisions to CM 10-02 and 10-09 for consideration

[2] CCAMLR-XXXIV/27, Proposal to strengthen monitoring and control of transshipments, 04 September 2015, Delegation of the USA

[3] CCAMLR-XXXV/24, Proposal to strengthen monitoring and control of transshipments, 02 September 2016, Delegations of Australia and the USA