CCAMLR

This document summarizes the debates and refers to the main documents of interest to CCAMLR, due to their direct relation to marine and oceanic issues, as presented during the Fourth Session of the United Nations Environment Assembly of the United Nations Environment Programme, in March 2019. In this respect, the debates surrounding micro-plastics and the impact of land-based activities on the marine environment are worth highlighting.

An international group of scientists, from the United Kingdom, Australia, Finland, France, Germany, Monaco, the United States and SCAR, including the majority of those holding long-term data and having experience of working with emperor penguins have formed an international collaboration to review the dependence and vulnerability of emperor penguins to ongoing and projected climate change. The outcomes of this work will have relevance to the ATCM, CEP and possibly CCAMLR because of its implications for species-related conservation decision-making and conservation planning.

The first annual meeting of the SCAR Krill Action Group (SKAG) met in Concarneau France on June 15th and 16th, 2019. The meeting  focused on several topics including  the  identification of  important  knowledge  gaps  in  krill  research  that  could  provide  data  in  support  of  the management needs of CCAMLR.

During late March to early April 2019, the annual random stratified trawl survey (RSTS) around Heard Island and McDonald Islands (HIMI) was conducted in CCAMLR Division 58.5.2, with the completion of 150 stations. The survey was conducted on the FV Atlas Cove. Sampling protocols such as the design and the duration of the hauls were similar to recent surveys, but with a new set of randomly selected station points. However, only 5 of 18 stations were sampled in Gunnari Ridge since the catch limit for Champsocephalus gunnari (mackerel icefish) in Division 58.5.2 was reached prior to the completion of the survey.

The catch of Dissostichus eleginoides (Patagonian toothfish) was 30.5 t which, while lower than last year’s survey, was still twice the average catch. The catch of mackerel icefish was higher than last year’s catch even though less than a third of the stations were completed in Gunnari Ridge. The catches of the other managed bycatch species, Channichthys rhinoceratus (unicorn icefish), Lepidonotothen squamifrons (grey rockcod) and Macrourus spp. (macrourids combined) were less than those of last year. Catches of skates were similar to those of the last three years, which have been higher than average. Invertebrate catch (including jellyfish) in the 2019 survey was lower than that of 2018, with anemones, poriferan sponges and sea stars in greatest abundance.

The calculated biomass for 2019 of the target species D. eleginoides and C. gunnari in the survey area were close to the highest estimates for the past 10 years. Biomass estimates for the managed by-catch species C. rhinoceratus and Macrourus spp. remained at a high level and the estimate for L. squamifrons remained as low as it was for the last 4 years. The 2019 biomass estimates for each of the three Bathyraja spp. (skates) were the highest in the last 10 years.

Length measurements and sex were taken for nearly 15 000 fish and for more than half of those, biological measurements were also recorded. Otoliths were collected from D. eleginoides (283) and a number of other species, and 466 toothfish were tagged and released.

The Fourth Meeting of the Scientific Committee (SC4) of the Southern Indian Ocean Fisheries Agreement (SIOFA) was held at the National Institute of Fisheries Science, in Yokohama, Japan from 25 – 29 March 2019. 

Takehiro Okuda (Japan) was the nominated CCAMLR Observer at the SC4 meeting and the CCAMLR Secretariat’s Science Manager attended  at the invitation of the Executive Secretary of SIOFA, Jon Lansley, as part of the ongoing development of collaboration between CCAMLR and SIOFA. The main areas of interest from a CCAMLR perspective were the discussion of SIOFA SC4 on VMEs, Patagonian toothfish catches and incidental mortality of seabirds.

SIOFA SC4 agreed that an increased level of interaction with CCAMLR was timely given the increased interest in fishing for Patagonian toothfish in SIOFA in areas adjacent to CCAMLR fisheries with full assessments.

For this study, Antarctic toothfish samples were collected from CCAMLR Subareas 48.2, 48.4, 48.6, 88.1, 88.2 and 88.3, Divisions 58.4.1, 58.4.2 and 58.5.2, and the SPRFMO area north of Subarea 88.1. Using approximately equal sample numbers spatially across CCAMLR Areas, DNA from 761 toothfish samples were extracted and of these 547 were deemed to contain sufficient quantity and quality to be sequenced by Diversity Arrays to identify variable nucleotide SNPs sites.

The analysis of SNPs indicated that the genetic structuring of Antarctic toothfish across the Southern Ocean is very weak. The sampled toothfish shared over 99.9% of the observed variation between sites. While some genetic differences could be attributed to the longitude the samples were collected from, these differences were not sufficient to assign samples back to their location.

The combination of large-scale egg and larvae dispersal and long-distance fish movement, even at only low levels, would be sufficient to contribute to the dissolution of the genetic stock structure and explain the results found in this study. However, the actual level of genetic stock exchange is difficult to determine.

Establishing MPAs for spatial management in the Convention Area requires the preliminary development of a unified approach and unified criteria supported with adequate scientific information and should be enshrined in CCAMLR conservation measures. Relevant proposals are discussed.

The Ross Sea region MPA Research and Monitoring Plan in its current form requires serious revision, refinement and further discussion by the Scientific Committee and its working groups (WG-SAM, WG-FSA) ahead of its discussion by the Commission. Comments and proposals are presented regarding the revision and improvement of the research and monitoring plan.

En réponse aux commentaires formulés lors de la réunion 2019 du WG-EMM, des explications sont données sur la procédure consistant à calculer les captures par périodes de deux heures sur les navires norvégiens utilisant le système de chalutage en continu dans la pêcherie de krill. La procédure, utilisée désormais sur tous les navires, consiste à diviser en périodes de deux heures la capture journalière mesurée par la balance (flow scale) en utilisant une distribution des captures estimées par périodes de deux heures calculées à partir du volume et du poids de krill dans la cuve, accumulés successivement toutes les deux heures. La méthode fusionne les deux méthodes décrites dans la MC 21-03 (annexe 21-03/B), mais contient des éléments qui ne figurent pas déjà dans la mesure. Ce document apporte un complément d'explication et illustre les relevés journaliers conservés par les navires, qui, depuis juillet 2019, peuvent être étudiés par la CCAMLR.  Reconnaissant l'absence de clarté sur la procédure par le passé, il est proposé que le Comité scientifique envisage d'inclure une référence à la procédure et un texte descriptif dans la MC 21-03.