The pre-exploitation krill biomass estimates, B₀, is essential for generating the Precautionary Catch Limit (PCL) for sound science-based krill fishery management. In 2019, a multi-member large-scale synoptic acoustic survey was conducted to provide krill biomass estimates for Area 48, whilst various mesoscale surveys were also conducted in Subarea 48.1. Krill biomass estimates for the four US AMLR strata has been provided by WG-ASAM e-group during the 2021 intersessional period. However, krill biomass estimates for the remaining area in Subarea 48.1 as required by the Scientific Committee has not been provided yet. To facilitate the development of the new management approach, here we provide the krill biomass estimates in Subarea 48.1 based on the up-to-date available acoustic surveys.

The Delegation of Norway would like to inform the Scientific Committee that a scientific knowledge base has been compiled to enable us to progress to a workshop in early 2022 to explore and jointly develop with CAMLR members and observers a range of candidate MPAs to inform a proposal for Weddell Sea MPA Phase 2. This working paper informs the Scientific Committee on the current status of: (i) the scientific knowledge base, (ii) status of the spatial layers for spatial planning, (iii) consultative process, (iv) chronology of documentation and, (v) intended tasks to further improve the scientific knowledge base.

With this working paper the Delegation of Norway invites CCAMLR Members and Observers to participate in a Workshop within the first half of 2022. The Workshop has the following objectives: i) to bring together relevant expertise from CCAMLR Members and Observers to explore spatial planning solutions for WSMPA Phase 2 and ii) to jointly identify a range of candidate spatial planning solutions for WSMPA Phase 2.

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.

Any spatial management units need to be clearly defined for CCAMLR fishery. To facilitate the development of the new krill management approach in Subarea 48.1, the boundaries of 5 candidate management units, including the 4 US AMLR strata adjusted for administrative purpose, and an extra stratum adjacent to US AMLR Strata to reflect proactively the need to manage the krill fishery in the Gerlache Strait area, are given together with the rationale behind the adjustment of the US AMLR Strata and the definition of the extra stratum. The sea surface area of the 5 strata are also given for easy reference.