Les estimations de la biomasse de krill d'avant l'exploitation, B₀, sont essentielles pour générer la limite de capture de précaution en vue d'une gestion solide de la pêcherie de krill fondée sur la science. En 2019, une campagne acoustique synoptique à grande échelle a été menée par plusieurs Membres pour obtenir des estimations de la biomasse de krill pour la zone 48 et diverses campagnes d'évaluation à méso-échelle étaient également effectuées dans la sous-zone 48.1. Pendant la période d'intersession 2021, l'e-groupe du WG-ASAM a fourni des estimations de la biomasse de krill pour les quatre strates de l'US AMLR. Les estimations de la biomasse du krill demandées par le Comité scientifique pour le reste de la sous-zone 48.1 n'ont toutefois pas encore été présentées. Afin de faciliter le développement de la nouvelle approche de gestion, nous présentons ici les estimations de la biomasse de krill dans la sous-zone 48.1 fondées sur les dernières campagnes acoustiques disponibles.

La délégation norvégienne souhaite informer le Comité scientifique de la compilation d'une base de connaissances scientifiques permettant d'organiser un atelier début 2022 afin d'étudier et de développer conjointement avec les membres et les observateurs de la CCAMLR une série d'AMP potentielles permettant d'étayer une proposition concernant la phase 2 de l'AMP de la mer de Weddell. Ce document de travail informe le Comité scientifique du statut actuel : i) de la base des connaissances scientifiques, ii) des couches spatiales pour la planification spatiale, iii) du processus de consultation, iv) de la chronologie de la documentation et v) des tâches prévues pour élargir la base de connaissances scientifiques.

Par ce document de travail, la délégation norvégienne invite les membres et les observateurs de la CCAMLR à participer à un atelier qui se tiendra au cours du premier semestre 2022. L'atelier a pour objectifs : i) de réunir l'expertise des membres et observateurs de la CCAMLR afin d'étudier des solutions pour la planification spatiale de la phase 2 de l'AMPMW et ii) d'identifier ensemble une série de solutions potentielles pour la planification spatiale de la phase 2 de l'AMPMW.

This paper presents the diagnostics associated with the 2021 48.4 Patagonian toothfish assessment.

This paper describes an updated CASAL based assessment of Patagonian toothfish (D. eleginoides) in Subarea 48.4. The assessment data are updated with the observations for the 2019 and 2020 seasons¹. Stock projections indicate that the stock was at 65% of B₀ in 2021 and that a yield of 23 tonnes in 2022 and 2023 is consistent with the application of the CCAMLR harvest control rule.

The assessment would lead to a recommendation from Working Group FSA to Scientific Committee that the catch limit for D. eleginoides in Subarea 48.4 should be set at 23 tonnes for 2021/22 and 2022/23.

¹  Seasons are referred to by the year that the CCAMLR season ends in, as this is when the fishing occurs, e.g. the 2020 season runs from 1^st December 2019 to 30^th November 2020.

This paper presents the diagnostics associated with the 2021 48.3 Patagonian toothfish assessment.

Assessment of the Patagonian toothfish (D. eleginoides) in Subarea 48.3 indicates that the current status of the stock is at 47% of B₀. Projections indicate that a constant catch of 2,072 tonnes in the 2022¹  and 2023 seasons would be consistent with the CCAMLR decision rule after accounting for recent mammal depredation rates.

The assessment would lead to a recommendation from Working Group FSA to Scientific Committee that the catch limit for D. eleginoides in Subarea 48.3 should be set at 2 072 tonnes for 2021/22 and 2022/23.

¹  The seasons are labelled according to calendar year in which the season finishes e.g. the 2020 season refers to the season from 1^st December 2019 to 30^th November 2020.

A summary of the intersessional work and discussion by the Risk Assessment e-group.

We provide an update on the implementation of the risk assessment in Subarea 48.1 resulting from discussions held during WG-EMM 2021. We have used track changes when adding textual changes incorporated since WG-EMM and all figures have been updated. In this version, we use an updated layer for winter krill density, evaluate some new scenarios and also include some sensitivity analyses.

We have applied the risk assessment framework, developed by Constable et al. (2016), to Subarea 48.1, with the aim of identifying the most appropriate management units by which to spatially distribute the local catch limit for the commercial fishery for Antarctic krill. We use the best available data for implementing the approach which was endorsed by the Commission in 2019. The framework is flexible and can accommodate new data to improve estimates of risk in the future.

We evaluated 36 catch distribution scenarios for assessing risks from krill fishing in Subarea 48.1. For each scenario we calculated the regional baseline risk, and the regional desirability risk. Baseline risk is defined as the risk to predators and krill and is based on predation pressure and the proportion of juvenile krill in each management unit. Desirability risk is defined as the risk to predators and krill as for the baseline risk, but also accounting for the desirability of a management area to the fishery i.e. more catch may be attributed to areas where the fishery has previously fished (desirable areas) than in the baseline scenario. We show that the spatial distribution with which the fishery currently operates presents some of the highest risks of all scenarios evaluated. Managing the fishery at much smaller scales has the lowest risk but may necessitate a high level of management interaction with the fishery.

This implementation can provide advice to CCAMLR for short-term management and could provide a template for the rest of Area 48. We highlight that each data layer impacts the outcome of the risk assessment and recommend that updated estimates of the distribution, abundance and consumption of krill, and estimates of available krill biomass will be key as CCAMLR moves forward to develop a longer-term management strategy.

A benefit of the risk assessment framework is that CCAMLR now has a tool for direct comparison of risks associated with alternative catch distributions at an appropriate spatial scale for management. We suggest one approach for choosing between scenarios, based on regional risk (either baseline or desirability).

We provide advice about the scale at which the krill fishery can be managed, but highlight important issues that should be discussed, including uncertainty, before CCAMLR agrees the design of spatial management units. We highlight that for the Risk Assessment to give a robust estimate of risk then it is important that the management units are at a similar scale as fishery operations. If management units are large, and the fishery operates in just a small portion of a particular unit, then the measure of risk estimated by the Risk Assessment will not reflect the risk posed by the fishery in that management unit.

Finally, we highlight that our endeavours have been the result of a community effort and we are grateful to those that have provided data and advice.

Toute unité de gestion spatiale doit être clairement définie pour les pêcheries de la CCAMLR. Afin de faciliter le développement de la nouvelle approche de gestion du krill de la sous-zone 48.1, les contours de cinq unités de gestion candidates, y compris les quatre strates US AMLR ajustées à des fins administratives, et une strate supplémentaire adjacente aux strates de l'US AMLR pour refléter proactivement la nécessité de gérer la pêcherie de krill dans la zone du détroit de Gerlache, sont fournis avec les motifs de l'ajustement des strates de l'US AMLR et la définition de la strate supplémentaire. L'aire de la surface marine des cinq strates est également donnée pour une référence.