We made two sensitivity runs of age-structured and two fisheries (≥1300 m and < 1300 m) CASAL models for stock status assessments of Dissostichus eleginoides in the research block 58.4.3a_1 following the recommendations of the WG-FSA-2014 meeting. Two runs were carried out: including or excluding the data from fish tagged in 2012.

The likelihood profiles for tagged fish released in 2012 for ELAN_1 model reflected a large number of recaptures of the tags released concentrated in the western area of research block. This is why the removal of 2012 tag release data boosted the MPD estimate of B0 in ELAN_2 model. The selectivity of the shallow fishery is poorly estimated in MCMC runs for ELAN_1 model. This is unsurprising as the length frequency of the shallow fishery presents two shifting modes in most years, and therefore cannot be fully fitted.

We recommend that the more conservative model (including the 2012 tag data) be used for management purposes. The median MCMC estimates of the initial and current biomass were 560 and 420 tonnes and the CCMLR yield for this stock was calculated at 27t.

Following the recommendation of WG-FSA in 2014 the Secretariat has undertaken an analysis of by-catch in CCAMLR longline fisheries. The numerical target catch ratio (the number of target fish as a proportion of the total number of fish caught), using haul by haul data from the Ross Sea toothfish fishery from 2008–2014, was used as a single metric to examine the amount of by-catch reported by vessels. This analysis indicated that, as expected, differences in this index arose due to gear and location of fishing. However, there was also evidence of distinct differences in the mean (and distribution) in the index from two groups of Members flagged vessels, that together contribute 84% of the haul by haul data. These differences do not appear to be explained by differences in gear or location and are also apparent in the data reported by observers. However, the way in which observer sampling of by-catch is reported requires clarification. In order to further develop the analysis of by-catch it is essential to consider what additional factors need to be included in that analysis. This consideration should also review whether there have been any misinterpretations of the data, or the assumptions underlying the analysis, that may have led to errors in the results and subsequent interpretation.

Result of the Russian research program in the Subarea 48.5 (Weddell Sea) in season 2012-2013 were analysed in accordance with the Scientific Committee recommendations (CAMLR-SC-XXXIII, par. 3.230 – 3.234).

Russian Federation is going to continue investigation for toothfish in Ross Sea in fishing seasons 2015-2018. The present program aims to recapture tagged fishes released during the implementation of the previous research program took place in 2010-2012 fishing seasons and investigate resource potential and life cycle of Dissostichus species within the eastern part of the Ross Sea over shelf and continental slope within the Subarea 88.2 A.

Over the last three years at the meetings of WGs and CCAMLR SC a question about research TAC in open and closed SSRUs of the Ross Sea has been raised. In accordance with established practice, as a rule, if research goes on in open SSRU then the necessary catch limits are taken from the unit`s TAC. If research fishing goes on in closed SSRU then as a rule catch limits are taken from the biggest TAC in the Ross Sea – from SSRUs HIK. This proposal is about establishing of research TAC in all closed SSRUs of the Ross Sea and the Amundsen Sea.

Closed mostly within the Weddell Sea Subarea 48.5 is one of the closed data-poor CCAMLR Subareas. Stock assessment of this area should be calculated basing on the newest and adequate data. Despite the difficult ice conditions the Weddell Sea is the largest enclosed near-continental sea of the Antarctic which is very similar to the Ross Sea in some respects like shape, bathymetrical profile and current system. Such similarity gives hope that the Weddell Sea could become one of the most promising areas for exploratory fishery of Dissostichus sp. and disperse fishing load from the Ross Sea. However, fishery in subarea 48.5 is closed based on absent stock assessment. The main objective of the present program is collecting data for reliable stock assessment and following estimation of precautionary limits in accordance with CCAMLR decision rules. The program contains several phases and prospected for 5 years. Detailed plan of fishing operations, collecting and analysis of data will be provided for the Scientific Committee and Commission consideration.

According to the direction of the XXXIII meeting of the Scientific Committee that data-poor area in the future would need to be consistent with the original research objectives approved in 2012 (SC-CAMLR-XXXIII, par. 3.233) in this work we present the original adopted research program in the Weddell Sea (WG-FSA-12/12) with minor revisions that reflect the current situation.

Exploratory fishing for toothfish (Dissostichus spp.) in Division 58.4.1 began in 2003. Robust stock assessment and catch limits according to CCAMLR decision rules remain to be determined for this Division. In 2008, only one vessel, Tronio, has conducted research fishing in accordance with a research plan submitted under CM 24-01. France notifies its wish to collaborate in this research fishery with the other participants over the coming years in order to participate in the tagging program and achieve a robust stock assessment. The aim is to collect sufficient data to provide an advice on a catch limit according to CCAMLR decision rules. This paper presents a proposal for a research plan for 2015/2016 developed under Conservation Measure 41-01. The biomass in the Division was estimated by research block during WG-FSA 2014 using CPUE x seabed analogy method. In the absence of an assessment using the CCAMLR decision rules, the catch limit should remain unchanged at 724 tonnes for 2015/16 to maximize the expectation of tag-recapture.