This document is devoted to studying species composition, spatial and vertical distributions, size composition and abundance of morids in the CCAMLR and adjacent areas. The main goal is to conserve these fishes and prevent them from disturbance in the Antarctic waters. This will be done by detection of areas and depths of their aggregations, by reveal of presence/absence of spatial and vertical migrations and by study of their seasonal and multi-annual variations. Results will be used for preparation of conservation measures allowing for preservation these vulnerable by-catch species from irreparable harm of destructive fishing.

This update to the annual krill fishery report contains background of the fishery as an introduction to the report, an inventory of catch and SISO data up to June 2016, including incidental mortality of marine mammals and seabirds as well as the CCAMLR approach to management of the krill fishery. Monthly catch maps for the last complete fishing seasons (2015) and the current season up to May 2016 have been included as an appendix. 

A multi-year research plan as outlined in CM 41-04 (2012, 2013 & 2014) was initiated in Statistical Subarea 48.6 by Japan and South Africa during the 2012/13 fishing season. Two vessels participated in the research project in each of the three fishing seasons and the progress achieved during the first 3.5 years is reported.

The emphasis of the progress report is on block 486_2, since more tag returns have been recovered from this block and a preliminary stock assessment has been conducted using data mainly from block 486_2.  

Model results and diagnostics for the integrated assessment model for krill in Subarea 48.1 are summarized. Alternative potential decision rules based on the distributions of krill spawning biomass during different reference periods, and potential catches associated with those rules, are described. The model and procedures outlined in this paper synthesize work reported to CCAMLR WG-EMM, WG-SAM, and WG-FSA in a number of papers since 2011. The assessment model for krill in Subarea 48.1 is offered as a tool for CCAMLR to use in managing the krill fishery in Subarea 48.1.

Catch at length is an important input into any stock assessment. Consequently, collecting length data from the catch is a task undertaken by all at sea observes in CCAMLR fisheries. Although analyses in the past have looked to the optimal design of the observer program, in terms of levels of coverage of vessels and hauls (e.g., Agnew et al., 2009; 2010), less attention have been focussed on how many krill should be measured by observers should measure (however see Thannasekos et al. 2012). We used C1 effort, catch and observer data from Subarea 48.1, collected between 2010 and 2015, to characterise how many krill are measured by observers, and for how many hauls. We then simulate the impact of different haul-wise sample sizes on the ability to estimate mean length in a sample per SSMU × month combination (effective sample size). The median number of krill measured per haul was around 200 (range 0-652). However haul-wise sample sizes of down to 50 did not substantially reduce the effective sample size, whereas increasing the number of hauls sampled did substantially increase the effective sample size. Therefore, we recommend that observers collect smaller samples (50) at the haul level, over a greater number of hauls to allow better estimates of catch at length.

At the EEM-15, it was agreed that detailed information on survey design of the dedicated cetacean sighting vessel-based krill (CSVK) survey by Japan, would be submitted with data from the first of these annual surveys to the next meeting of WG-SAM (2016), to assess the survey design, in particular the trade-offs between the primary goal of gathering information on cetaceans versus the secondary goal of gathering information on krill. This paper summarizes the information of survey design and results of the first CSVK survey in East Antarctica (115°-130°E) conducted during the 2015/16 austral summer season. The survey was designed for the main purpose of obtaining systematic sighting data for whale abundance estimates. Along the sighting track-lines, krill survey (based on echo-sounder and net sampling) and oceanographic survey (based on CTD) as well some feasibility studies on biopsy sampling and telemetry in Antarctic minke whales, and routine photo-id and biopsy sampling on large whales, were also conducted. Technical input from the WG-SAM 16 will be useful to improve the survey plan for the next multidiscipline survey in 2016/17. 

This paper presents a proposal for a longline survey connecting the currently undertaken surveys in Subarea 48.2 with the established fishery in Subarea 48.4. The research objectives include determining population connectivity between these Subareas, improving understanding of Dissostichus sp population structures in this region, and improving available data on bathymetry and associated distributions of benthic bycatch species. This proposal includes a three-year data collection and two-year data analysis plan towards the development of a stock hypothesis for the northern regions of 48.2 and southern regions of 48.4.

Depredation is experienced by several fisheries within the CCAMLR Area, however not all fisheries have a data collection programme that is sufficiently long established, or detailed, to allow for model estimation of the lost catch. A new method was developed in 2014 that used an observed change in ratios of toothfish to grenadiers on depredated longlines, and proved to estimate losses similarly to a depredation model. Here this method was adapted for Subarea 48.3 and compared to the outputs from an alternative long-standing model estimation approach feeding into the CASAL assessment for toothfish. The new method performed similarly to the established method both in estimating total losses, and identifying spatial patterns.

Three Korean fishing vessels conducted toothfishes longline fishery in Southern Indian Ocean area (i.e. Area 51) from 2011 to 2013, and information on the collected 10 CCAMLR tag recaptures is being submitted.