North Atlantic Albacore MSE
(Thunnus alalunga)
Generated by ChatGPT on 15 Feb 2026
Overview
MSE work for northern albacore started in 2013 (Kell et al., 2014) and officially with Rec. 15-04 where management objectives were adopted and the development of a Harvest Control Rule (HCR) was requested by the Commission. The development of the interim HCR at ICCAT was based on simulations conducted using a specifically designed MSE framework. The ICCAT Commission adopted an interim HCR for North Atlantic albacore in 2017 (Rec. 17-04), representing the first HCR adopted by ICCAT. The software and code used for the simulations, was reviewed in 2018 (Sculley, 2018). In 2021, the Commission adopted a full long-term Management Procedure (MP), including the Exceptional Circumstances Protocol (ECP) for North Atlantic albacore (Rec. 21-04, Annex 2). The Commission has set the Total Allowable Catches (TACs) since 2017 using the interim HCR and the MP for northern Atlantic albacore (Rec. 17-04; Rec. 21-04; Rec. 23-05). The SCRS evaluates the existence of Exceptional Circumstances (ECs) every year and ECs have not been invoked since 2022.
| OMs Developed in 2013-2017 |
MP Adopted in 2017/2021 |
ECP adopted in 2021 |
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| Recondition in 2024-2026 |
MP since 2017 | ECs evaluation No EC since 2022 |
History
The MSE process for northern albacore has evolved through a series of ICCAT Recommendations and SCRS initiatives over more than a decade. The process was initiated following concerns about the sustainability of the stock and the need for more robust, precautionary management frameworks. Rec. 09-05 initiated the rebuilding plan for northern albacore, aiming to restore biomass to levels consistent with Maximum Sustainable Yield (MSY). Rec. 11-04 requested the SCRS to develop a Limit Reference point and Rec. 13-05 called for the SCRS to begin evaluating Harvest Control Rules (HCRs), laying the groundwork for MSE development. In 2015, the SCRS identified northern albacore as a priority candidate for the application of MSE, noting the availability of data and scientific interest. Rec. 15-04 established the management objectives for the stock and explicitly requested the SCRS to develop HCRs and a dialogue process with the Commission to support the development of an MSE process.
The 2016 stock assessment further motivated this work by confirming the rebuilding trajectory of the stock, while also emphasizing the need for evaluating long-term strategies under uncertainty before any TAC increase. Rec. 16-06 provided the performance metrics that the SCRS used to evaluate alternative HCRs under uncertainty. In 2017, the Commission adopted an interim HCR (Rec. 17-04) and increased the Total Allowable Catch (TAC) based on it. From 2017 to 2021, an iterative development and peer review of the MSE framework took place under the guidance of the SCRS Albacore Species Group and Panel 2, that culminated in a formal adoption of a Management Procedure (MP) through Rec. 21-04. Since then, this MP has been used to set the TAC every 3 years.
Operating Models (OMs)
The OMs represent a range of plausible dynamics for the northern albacore stock. The reference set of 132 OMs includes the main sources of uncertainty identified by the SCRS in the stock assessments. These include uncertainty in biology (steepness, natural mortality), data weighting (size, CPUE, tagging), structure of the time series and fishery dynamics (selectivity and catchability). The outputs of Multifan-CL based stock assessment scenarios, updated with data up to 2020, were used to condition the 132 OMs. The OMs were conditioned using libraries from the FLR-project (github.com/flr).
In accordance to Rec. 21-04 para 18, the SCRS has been developing a new MSE framework to support the possible adoption of a new Management Procedure (MP) by the Commission. The new OMs are based on the Stock Synthesis models used in the 2023 stock assessment (Anon., 2023), and have been conditioned with the MSE framework FLBEIA. Details can be found in the Trial Specification Document.
| Materials | ||
| More materials can be found in References | ||
| OM developed in 2013-2017 | ||
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| Summary | MSE Codes | |
| OM Recondition in 2024-2026 | ||
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| Summary | MSE Codes | Shiny App |
| Under development | ||
Management Objectives
| Stock Status | Safety | Yield | Stability |
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| Prob. >= 60% in green quadrant | Decrease F as soon as possible when B<BMSY | Maximize overall catch | Minimize inter-annual fluctuations in TAC levels |
Candidate Management Procedure (CMPs)
Only Model-based Harvest Control Rules (HCRs) were considered, with varying parameters of the hockey-stick HCR as well as alternative stability closures.
Management Procedure (MP)
The Commission adopted an interim Harvest Control Rules (HCRs) in 2017 (Rec. 17-04) and formally adopted a full Management procedure in 2021 (Rec. 21-04).
| The MP shall be applied to set a 3-year constant annual Total Allowable Catch (TAC). A production model (with defined inputs and specifications) is applied and the hockey-stick type HCR determines the level of fishing mortality to apply in the next 3-year period, depending on the estimated stock status, with a maximum of 0.8*FMSY , and decreasing fishing mortality as soon as B is estimated to be below BMSY . The maximum TAC allowed is 50.000 t, and TAC variations are limited to +25%/-20% if B>BMSY . |
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| Rec. 21-04, Annex 2 |
Exceptional Circumstances (ECs)
The Commission adopted the Exceptional Circumstances Protocol (ECP) in 2021 (Rec. 21-04 Annex 2).
The SCRS evaluates, annually, the existence of Exceptional Circumstances (ECs) that would preclude the application of the Management Procedure (MP).
There have been no ECs invoked since 2022.
Principles of ECs a: When there is evidence that the stock is in a state not previously considered to be plausible in the context of the management strategy evaluation (MSE); |
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| EC Protocol: Rec. 21-04, Annex 2 |
References of North Atlantic Albacore
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| Year | Ref | Document |
|---|---|---|
| 2025 | Capacity building | How to efficiently craft a management procedure |
| 2025 | Capacity building | Management Procedures and Management Strategy Evaluation: A Brief Guide for Managers |
| 2025 | Capacity building | Management procedures versus traditional fisheries management |
| 2025 | Codes | FLBEIA Code |
| 2025 | Codes | NALB MSE Codes |
| 2025 | Harvest Strategies Glossary | Harvest Strategies Glossary |
| 2025 | IOTC | IOTC MSE capacity building tools |
| 2025 | SCRS/P/2025/003 | MSE Simulations to evaluate North Atlantic Albacore HCR with FLBEIA and considering SPiCT as assessment model in the MP. |
| 2025 | SCRS/P/2025/009 | Proposal on the ICCAT MSE website by Ad-hoc Sub-group on MSE Communication |
| 2025 | SCRS/P/2025/072 | Final reference and robustness Operating Models for the North Atlantic albacore MSE. |
| 2025 | SCRS/P/2025/073 | Observation Error Model for the North Atlantic albacore MSE. |
| 2025 | SCRS/P/2025/074 | Evaluation of alternative MPs for North Atlantic albacore using MSE. |
| 2025 | SCRS/P/2025/112 | Evaluation of Exceptional Circumstances for North Atlantic albacore in 2025 |
| 2024 | Capacity building | Assessment of Candidate Management Procedures and Harvest Control Rules for the Western Atlantic Skipjack Tuna |
| 2024 | Capacity building | How is MSE based MPs different from current stock assessment practice? |
| 2024 | Capacity building | HOW TO PUT A MANAGEMENT PROCEDURE TOGETHER |
| 2024 | Capacity building | Management Procedure Elements |
| 2024 | Capacity building | Objective of MSE simulations |
| 2024 | Capacity building | Reference Points & Rules: Managing fisheries for the future |
| 2024 | Capacity building | Restoring Pacific saury to a predictable and productive fishery |
| 2024 | Capacity building | What is an MSE based MP? |
| 2024 | SCRS/P/2022/029 | Updated summary on North Atlantic ALB MSE |
| 2024 | SCRS/P/2022/050 | Evaluation of exceptional circumstances for North Atlantic albacore in 2022 |
| 2024 | SCRS/P/2023/010 | Evaluation of exceptional circumstances for North Atlantic Albacore in 2023 |
| 2024 | SCRS/P/2023/013 | Preliminary Stock Synthesis assessment model for northern Atlantic Albacore |
| 2024 | SCRS/P/2023/049 | Updated summary on North Atlantic albacore MSE |
| 2024 | SCRS/P/2023/075 | Updated indicators of Exceptional Circumstances |
| 2024 | SCRS/P/2023/107 | Stock Synthesis (SS3) Model For North Atlantic Blue Shark Kobe Plot Distribution Sensitivity Analyses |
| 2024 | SCRS/P/2024/027 | Evaluation of exceptional circumstances for North Atlantic albacore in 2024 |
| 2024 | SCRS/P/2024/028 | Operating models for the new management strategy evaluation framework for North Atlantic Albacore |
| 2024 | SCRS/P/2024/029 | Observation error model for the new Management Strategy Evaluation framework for North Atlantic albacore |
| 2024 | SCRS/P/2024/030 | Evaluation of the performance of the North Atlantic albacore MP (Recommendation 21-04) under the new grid of Operating Models for North Atlantic albacore |
| 2024 | SCRS/P/2024/063 | Update of the North Atlantic albacore MSE |
| 2024 | SCRS/P/2024/073 | Observation error model for the new Management Strategy Evaluation framework for North Atlantic albacore |
| 2024 | SCRS/P/2024/074 | FLBEIA: A simulation model to conduct Bio-Economic evaluation of fisheries management strategies |
| 2024 | SCRS/P/2024/078 | MSE Process Scorecard for ICCAT Stocks |
| 2024 | SCRS/P/2024/098 | Migration to the new MSE framework for North Atlantic albacore |
| 2024 | SCRS/P/2024/099 | Development of an observation error model for North Atlantic albacore |
| 2023 | Capacity building | Two Tools Can Help Make Ecosystem-Based Fisheries Management a Global Reality |
| 2023 | openMSE | Open Source Software for Management Strategy Evaluation |
| 2023 | SCRS/P/2023/051 | A Review of Reference Points, Objectives, and Performance Standards at tRMFOs |
| 2022 | Capacity building | To Strengthen Fishery Management, RFMOs Should Use Science-Management Dialogue Groups |
| 2021 | Capacity building | Harvest strategies: Fisheries Management for the 21st Century |
| 2021 | Codes | openMSE Code |
| 2021 | SCRS/P/2021/023 | Summary on North Atlantic ALB MSE |
| 2020 | SCRS/P/2020/016 | Summary on North Atlantic Albacore MSE |
| 2019 | Capacity building | Harvest Strategies: 21st Century Fisheries Management |
| 2019 | ICCAT WS | ICCAT MSE Introductory Workshop in 2019 |
| 2019 | SCRS/P/2019/019 | Summary of North albacore MSE |
| 2018 | SCRS/P/2018/019 | Current state of MSE/HCR Process in ICCAT |
| 2018 | SCRS/P/2018/020 | What makes an MP an MP and an MSE an MSE? |
| 2018 | SCRS/P/2018/021 | Operating model for North Atlantic swordfish (Xiphias gladius) |
| 2018 | tRFMO MSE Glossary | Glossary of terms for harvest strategies, management procedures and management strategy evaluation |
| 2018 | tRFMO MSE meeting | REPORT OF THE 2018 JOINT TUNA RFMO MANAGEMENT STRATEGY EVALUATION WORKING GROUP MEETING (Seattle, USA – 13-15 June 2018) |
| 2018 | tRFMO MSE Working Group | Joint Tuna RFMO Management Strategy Evaluation Working Group |
| 2016 | Capacity building | Harvest Control Rules |
| 2016 | Capacity building | Management Objectives |
| 2016 | Capacity building | Management Strategy Evaluation for Fisheries |
| 2016 | Capacity building | Reference Points |
| 2015 | Capacity building | Harvest strategies |
| 2014 | IATTC SAC-05-10b | MANAGEMENT STRATEGY EVALUATION (MSE) IMPLEMENTATION IN STOCK SYNTHESIS: APPLICATION TO PACIFIC BLUEFIN TUNA |
| 2014 | ICES Journal of Marine Science, 71(2): 195–203 | Implementing harvest strategies in Australia: 5 years on |
| 2003 | North American Journal of Fisheries Management, 23: 349–361 | Targets and Limits for Management of Fisheries: A Simple Probability-Based Approach |
| 1998 | Canadian Journal of Fisheries and Aquatic Sciences, 55(6): 1545–1552 | Recent international agreements and the precautionary approach: new directions for fisheries management science |
| 1996 | FAO | FAO precautionary approach to capture fisheries and species introduction |