This paper presents the latest developments in models for Crozet following the more recent ones (Sinègre & Duhamel, 2016) with an updating of input data from the more recent years (up to 2016/17 season) and a reassessment of stocks taking into account the previous remarks of the WG-FSA meetings.

This paper presents the latest developments in model of Kerguelen with an updating of input data from the more recent years (up to 2016/17 season) and a reassessment of stocks taking into account the previous remarks of the WG-FSA meetings.

In 2017, a bottom trawl survey (PoKer 4) was undertaken at Kerguelen Islands (Division 58.5.1) to collect information about the size distribution and the biomass status of mackerel icefish, Champsocephalus gunnari. Data from this random stratified trawl survey was used for a short term assessment of C. gunnari on Kerguelen EEZ. The standard CCAMLR methods were used to provide potential yields, a catch limit of 3081 t is recommended for 2017/2018 and 2753 t for 2018/2019.

The indices of exploratory toothfish fishery in the Subareas 881 and 88.2 for the period of 2010-2016 are considered. Taking into account the different number of hooks at longlines sets used at the fishery, the catch indices were normalized to 1000 hooks.  The effect of the gear types (autoline, spanish, trotline) on the observed spatial-temporal variability of CPUE toothfish (kg/1000 hooks), by-catch CPUE (kg/1000 hooks) and normalized target catch ratio is considered. Particular attention was focused to the analysis of the length-species compositions of catch by years and SSRU while using different types of longlines. Our results  show that the gear type  is the most important factor that must be taken into account both during the longline fishery data analysis and the research programs planning.

Electron subantarctic (Electrona carlsbergi) is one of important pelagic myctophidae which circumpolar distributed between the warm waters of the subtropical confluence zone and the Southern Ocean. The distribution, life history and migration pattern of this species were examined using the biological data in 1990s, however, the habitat shift of this species was still unclear. The present study examined Sr:Ca ratio of otolith section for E. carlsbergi from nucleus region to edge and validated the habitat shift of this species using otolith elemental signature analysis. Otolith samples were collected from northern South Shetland Islands during January 2010 (9 individuals), January 2013 (5 individuals) and February 2016 (9 individuals) from krill fishery, respectively. The results demonstrate E. carlsbergi hatched in two different areas, E. carlsbergi with Type I otolith could hatched in the oceanic waters of sub-Antarctic zone and spend the first year of life in this region. Those individuals move across different fronts into the Antarctic waters from the warmer waters after age 1. E. carlsbergi with Type II otolith could hatched in the coastal waters and are transported (or moved positively) across sub-Antarctic Front into the open waters (oceanic regions of APFZ) with the influence of eastward movement of strong ACC system. The present study reveals otolith elemental signature analysis can be used to test habitat shift and life history processes of fish species in the Southern Ocean. Moreover, otolith elemental signature analysis with coupling to water chemistry can be useful to ascertain migration routes of E. carlsbergi.

Length-weight relationships (LWRs) of six fish species in the Southern Ocean, which commonly associated with Antarctic krill fishery, were determined. Samples were collected with Chinese krill trawler (codend mesh size 2 cm) in the Atlantic sector of the Southern Ocean from January to August 2016. Data on LWRs and the relationships between standard length and total length of those species were presented. Those data on fish species derived from Antarctic krill fishery will be very helpful in understanding the interaction between krill fishery and fish community which associated with krill swarms. Data from krill fishery can provide a useful scientific platform to produce biological information of species associated with krill population.

Submissions for new research proposals and data collection programmes on D. mawsoni in Subarea 48 have recently become widely dispersed with little co-ordination or integration into existing programmes and their objectives. Without regional co-ordination, research in this area is unlikely deliver the objectives of the Commission, across the whole of Area 48.

Co-ordinated by WG-SAM and/or FSA, a high level strategic approach will allow the formulation of research hypotheses and associated objectives that allow proponents to design their proposals and provide a structure against which the research and results can be subsequently evaluated. A time schedule, in the form of a project plan with milestones, would allow the Scientific Committee to evaluate where gaps were not being addressed, evaluate success or failure, and also enable Scientific Committee to inform Commission as to progress towards meeting its objectives for management of the Convention Area.

Assessment of the Patagonian toothfish (D. eleginoides) in Subarea 48.3 indicates that the current status of the stock is at 51% of B₀. Spawning biomass has been increasing in recent years. Projections indicate that a constant catch of 2 600 tonnes in the 2017/18 and 2018/19 seasons would be consistent with the CCAMLR decision rule.

Marine debris data were collected at Bird Island and King Edward Point, South Georgia, at Signy Island, South Orkneys and at Goudier Island, Antarctic Peninsula for the period April 2016 to March 2017. Surveys of beached marine debris at Bird Island recorded a total of 244 items during austral winter (April to September 2016) and 499 items during summer (October 2016 to March 2017). Twelve items of beached debris were recorded at Signy Island (operational during summer only; 19 November 2016 to 22 March 2017). Sixty-four items of beached marine debris were recorded at Goudier Island (operational 13 November 2016 to 1 March 2017), which is the highest number since observations began in 2010/11. Entanglements of two Antarctic fur seals were observed at Bird Island and one at Signy Island, with three instances of entangled fur seals and the first record of an entangled elephant seal at King Edward Point. No marine mammal entanglements were recorded at Goudier Island. In total, 131 items of marine debris were found in association with seabird colonies at Bird Island, most commonly in association with wandering albatrosses (90 items; 69 %). There were no observed incidences of hydrocarbon soiling or entangled seabirds at any site during the reporting period. Overall, the occurrence of beached marine debris was above the long-term mean at both Bird Island and Goudier Island but below the mean at Signy Island. The incidence of marine mammal entanglements was below the long-term mean at all sites surveyed. Debris associated with seabird colonies was above the mean level for wandering albatrosses and grey-headed albatrosses, but below the mean for black-browed albatrosses and giant petrels.