CCAMLR

The move from Stage 1 to 2 in feedback management (FBM) for the Antarctic krill fishery is of critical importance to CCAMLR. Useful proposals at WG-EMM-16 this year highlighted strategies that could be used to do this, and ASOC encourages CCAMLR to develop a plan for discussion of these proposals and to improve the collection of data needed to implement them. In particular, the enhancement of data collection by fishing operators and from CEMP will be critical to progressing FBM. Another outstanding need is the ability to quantify krill flux, a factor that creates considerable uncertainty for management of the fishery. Finally, CCAMLR should re-examine the data sampling program for the krill observer program and make changes as necessary to improve the quality of data collected. In general, CCAMLR should give high priority to obtaining the data required for FBM and agreeing a strategy for putting FBM into practice.

Marine mammal interactions with fisheries are a growing major world-wide issue with both substantial ecological and economic consequences. Most longline fisheries operating around the world are seriously affected by these interactions i.e. marine mammals eating fish directly from fishing gear.

To begin addressing these issues globally, the first international workshop dedicated to odontocete depredation on demersal longlines operating in high latitudes was organised by the Coalition of Legal Toothfish Operators (COLTO) in Punta Arenas, March 2016. This workshop emphasised the urgent need to find global solutions to this issue.

The workshop concluded that routine data collection framework across fisheries confronted with interactions with odontocetes is important for a better understanding of depredation and for solutions to be developed, both locally and globally.

Using the COLTO workshop as an excellent example of international science, industry, government and NGO collaboration, this resulting document aims to provide basic guidelines for observer programmes that are relatively new to dealing with marine mammal interactions or are interested in expanding their observation efforts. It is based on ten years of experience around the islands of Kerguelen and Crozet (Southern Indian Ocean).

Depredation caused by killer whales and sperm whales on the Patagonian toothfish (Dissostichus eleginoides) fishery off Kerguelen and Crozet EZs are amongst the most important in the Southern Ocean. This paper presents the first results of depredation rates calculated on a yearly basis using the CPUE method.

Being able to correctly identify species is crucial in observer’s tasks and data quality implies very good knowledge from observers. Identification quality is related to observer’s training and resources provided by technical coordinators.

This document is updating the original tool described in WG-FSA-15/75, developed as  a “serious game” for observers to more easily learn species names before to go at sea or when steaming for example.

Preliminary results of a pop-up satellite tag (PSAT) on large Antarctic toothfish are described in this report. The toothfish was caught in the Mawson Sea in Feb 2015 and released with a PSAT by a Korean scientific observer. The same observer recovered the fish a year later. The days of liberty were over a year (366 days). The vertical movement of the fish shows strong and contrasting patterns. The most significant pattern was the fish staying at the same depth for a couple months. The vigorous diel vertical movement period followed after. It occurred during winter to early spring that it may be indicating the possibility of a spawning behavior.

We measured concentrations of 15 perfluorinated compounds (PFCs) in muscle tissues of Antarctic toothfish (n=113), and investigated accumulation patterns of PFCs in female and male muscles. The total PFCs (Σ₁₅PFCs) were ND (not detected) to 2.98 ng/g wet weight (ww) in muscle tissues with 0.32 ng/g ww of median concentration. The main compounds among PFCs were perfluoro-n-hexanoic acid and perfluoro-n-pentanoic acid. PFCs concentrations and compositions were significantly different between male and female. The levels of PFCs in the present study are comparable to those reported in 31 fish species from Korean coastal waters (0.27-4.81 ng/g ww). The concentrations of Perfluoro-1-octanesulfonate in the present study were much lower than environmental quality standard for biota (9.1 ng/g ww) by EU Water Framework Directive.

To identify the important prey items for pre-recruit Antarctic toothfish in the SSRUs 58.4.1.C, 58.4.1.G, 58.4.1.E, and 58.4.2.E, their stable carbon and nitrogen isotope ratios were determined. Sampling efforts were made during a longline survey of pre-recruit toothfish from commercial fishing vessel. In the previous studies, similarities in total FA compositions and the FA profiles in muscle tissue of Antarctic toothfish, bycatch specimen and icefish in the stomachs indicated a trophic connection between the toothfish and icefish. In this study, similarities in the δ13C values δ15N values of Antarctic toothfish indicate they occupy same trophic position irrespective of the area, body size, sex, and gonadal maturity. The combination of stable isotope ratios and fatty acid profiles can be effectively used to trace the trophic transfer from organic matter sources to higher trophic levels through food chains. Further studies on the trophic relationship between Antarctic toothfish and other animals by collection and subsequent biomarker analyses such as stable isotope analysis after lipid extraction, stomach contents analysis, and fatty acid analysis are needed to better understand the carbon flow through the Antarctic ecosystems.

This paper presents an update of the metrics of capacity and capacity utilisation presented in WG-SAM-14/19 and WG-FSA-15/09 in order to monitor trends in capacity in exploratory toothfish fisheries in Subareas 88.1 and 88.2. The updated metrics show the same pattern as the metrics based on the data up 2016 and do not indicate an excess capacity in the fishery. As indicated previously, based on a measure of potential daily fishing capacity and the catch limit for an area the notified fishing capacity in some management areas is in excess of the level that would allow the Secretariat to forecast and issue a timely closure notice using the current fishery forecasting procedure.