In this paper we consider whether the CCAMLR fishing season for Antarctic krill should start at a time of year that is based upon ecological events, rather than upon a date that is convenient for management. We review data on the breeding phenology of predators, and use data from the CCAMLR Statistical Bulletin (Version 28) to explore whether there are times of year that would reduce the potential for competition between land-based krill-eating predators and the fishery.

The marine ecosystem associated with the ocean shelves around South Georgia and the South Orkney Islands is highly productive, with a history of commercial exploitation. Many of the key oceanographic and ecological processes that determine the structure and functioning of this ecosystem operate over small scales of <10 km. Historically, these fine spatial scales have been poorly represented in numerical models. Here we describe the development of two regional ocean models that will be used to examine the detailed oceanography of the South Georgia and South Orkney Islands shelves and surrounding regions. The models are regional applications of NEMO with a ~3 km horizontal resolution, and include key physical processes of relevance to the local ecosystems including tides, atmospheric forcing from reanalysis, a seasonal glacial melt cycle, and with sea ice processes incorporated using LIM3.  The models will be used to generate a ~20 year time series of oceanographic flows and water mass properties, which will provide a numerical basis for detailed examination of the controls on the distribution of krill and fish around the islands, their interactions with predators and availability to fisheries. Such detailed analyses will help inform WG-EMM activities aimed at developing spatial and feedback management procedures.

The Antarctic toothfish (Dissostichus mawsoni Norman, 1937) is one of the main target species of commercial fisheries in the Antarctic. It is an endemic and is found along the shelf of Antarctica, as well as on the slopes of seamounts, underwater elevations and islands in the sub-Antarctic. It feeds on a variety of fish and cephalopods and can be an intermediate/paratenic host of some helminthes, whose final hosts are whales, seals, large rays and sharks. This article presents new data on toothfish infection in the Pacific sector of the Antarctic. Specimens were examined during commercial longline fishing in the Ross Sea and the Amundsen Sea in January-February 2013. Fourteen species of parasites were found using standard parasitological methods and genetic analysis.

Lipid metabolism and indices of oxidation processes obtained during examination of specimens of Antarctic toothfish Dissostichus mawsoni (Perciformes: Nototheniidae) caught in the Ross Sea are given. Blood plasma, tissues mesonephric kidney, liver and spleen were studied for the content of total lipids and lipid composition, products of lipid peroxidation and level of antioxidant protection. Biochemical status of immune organs depending on the structural and functional characteristics of tissues was established.

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.