Norway proposes a plan to investigate the toothfish populations in the Statistical Subarea 48.6 in 2017/18 using standardised longline gear, established tagging techniques, and pop-up tags. This initial year will be used for exploration with particular emphasis on tagging efforts and habitat mapping, and the study will adhere to principles and guidance expressed in CM 41-01. In future years the aim is to expand the investigation and involve additional collaborating members. New Zealand has been contacted and discussions have started on collaboration from the 2018/19 fishing season. The expectation is that in 2018 a new Norwegian vessel will be available, equipped with advanced technology for sampling and observation. The proposed research is pertinent to issues raised by the Scientific Committee (SC-CAMLR-XXXV, paragraph 3.3.252-3.265) and will supplement and expand existing efforts to characterise the local toothfish populations in the area to better understand stock structure, movement patterns and improve estimation of population characteristics and thereby contribute to the development of spatial population models. Additional outcomes of the research relate to mapping the bathymetry of the fishable area, documenting relative abundance of Patagonian and Antarctic toothfish, tagging toothfish for biomass estimation and for stock linkage studies, and collecting information on distribution, relative abundance, and life history of bycatch species.

Exploratory fishing for toothfish (Dissostichus spp.) in East Antarctica (Divisions 58.4.1 and 58.4.2) began in 2003. Robust stock assessments and catch limits according to CCAMLR decision rules remain to be determined for these Divisions. WG-FSA-16/29 outlines the first multi-member toothfish exploratory fishery research plan for East Antarctica, including research objectives, methods and milestones in accordance with ANNEX 24-01/A. In 2016, the Scientific Committee agreed that the research plan was appropriate to achieve its objectives (SC-CAMLR-XXXV, para. 3.244). We present here a proposal for the continuation of the research plan as set out in WG-FSA-16/29. All significant changes to the plan are outlined in Section A. A summary of data collection in 2016/17 (Section B), and issues arising from the 2016/17 season (Section C) are also provided.

In Division 58.4.3a, since 2012, research fishing has been conducted in the research block by two vessels using longlines: Shinsei Maru No. 3 (Japan) and the Saint André (France). The catch limit for Dissostichus spp. is 32 tons in 2014/2015 and the total reported catch up was 16.3 tons. For the last season (2015/16), the catch limit was unchanged (32 tons) but no catch up was reported due to engine damage for the French vessel and no fishing activity in the area for the Japanese vessel. The first Franco-Japanese exploratory longline fishery research plan for Dissostichus spp. in Division 58.4.3a (WG-FSA-16/55) was presented to WG-FSA-16, which included research objectives, methods and milestones in accordance with Conservation Measure 41-06 and associated measures. In October 2016, the Scientific Committee agreed that the research plan is appropriate to achieve its objectives (SC-CAMLR-XXXV, para. 3.251), and recommended to carry on a couple of investigations for the following years (SC-CAMLR-XXXV, para. 3.250). France and Japan commonly notifies their intention to continue their exploratory fisheries in Division 58.4.3a over the coming years in order to contribute to the tagging program and to achieve a robust stock assessment. We present here a proposal for the continuation of the research plan as set out in WG-FSA-16/55, and taking into account the Scientific Committee’s recommendations.

South Africa and Japan made the next season’s (2017/18) research plan in Subarea 48.6 using the latest CCAMLR C2 and Observer data. We have used extracted data provided by CCAMLR secretariat on 10^th May, 2017.

The estimated median stock size in research block 48.6_2, 48.6_3, and 48.6_4 was 5657.54, 5162.26, and 8211.25 tonnes, respectively, in Chapman method considering tags released in the last one years as effective for the biomass estimation, except for 48.6_4 with the last three years. The estimated median stock size in block 48.6_2, 48.6_3, and 48.6_4 was 801.17, 124.71, and 981.91 tonnes, respectively, in CPUE analogy method (reference area: RSR) using 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.