ICCAT MSE for other species

Overview

This page summarizes the development of closed-loop simulation and Management Strategy Evaluation (MSE) processes under ICCAT for four key species/stocks:

Southern Albacore
Southern Swordfish
Blue Sharks
North Atlantic Porbeagle

Each section outlines ICCAT recommendations (if applicable), operating model development, candidate management procedures, and progress.

South Atlantic Albacore

ICCAT Recommendations and Objectives

Rec. 24‑09 (2024) outlines the initial operational management objectives to support the development of a Management Strategy Evaluation (MSE) for South Atlantic albacore. Key elements include:

A call for ICCAT to adopt a candidate Management Procedure (MP) for Southern Albacore by 2029, with an interim BLIM set at 40% of spawning stock biomass at MSY (SSBMSY), unless otherwise advised.
A set of operational objectives to guide MSE design:
Stock status: ≥ 60% probability of remaining in the green quadrant of the Kobe plot over a 30-year projection.
Safety: ≤ 15% probability of falling below BLIM at any point in the projection period.
Yield: Maximize overall catch levels.
Stability: TAC changes between management periods should not exceed ±20%.
A proposed 3‑year management cycle for initial implementation.
A provision for revising these objectives by Panel 3, in consultation with the SCRS Albacore Species Group, with final objectives to be submitted by 2029.
These objectives define a transparent decision-making framework for operating models and candidate MPs during the S‑ALB MSE process.

Progress

Initial scoping conducted by the SCRS Albacore Species Group
Operating model development is anticipated in coordination with updated assessments.
Performance metrics and stakeholder engagement will follow SCRS guidelines.

South Atlantic Swordfish

ICCAT Recommendations

Although no formal MSE has been mandated for Southern Swordfish, the SCRS has acknowledged its potential utility and continues to evaluate stock status and management options.

Progress

Initial scoping conducted by the SCRS Albacore Species Group
Operating model development is anticipated in coordination with updated assessments.
Performance metrics and stakeholder engagement will follow SCRS guidelines.

Blue Sharks

ICCAT Recommendations

While a formal MSE process has not yet been launched for Blue Shark, several ICCAT recommendations call for the evaluation of feasibility:

Rec. 21-09: Requests the SCRS to explore the feasibility of developing an MSE for Blue Shark.
Rec. 22-08: Reiterates this request and establishes the basis for analytical development.

MSE-Related Updates

The SCRS has advanced the outlook for Blue Shark MSE through two key documents prepared in 2024. These focus on developing code architecture, conducting preliminary closed-loop simulations for the northern stock, and assessing technical feasibility.

Taylor (2024) presents a compact closed-loop simulation framework for Blue Shark MSE that uses multivariate Bayesian priors for life-history parameters and tests ICCAT-relevant management procedures against minimum performance standards. Example simulations show that several MPs—both index- and model-based—achieve high probabilities (>90%) of remaining above 40% BMSY, with green quadrant probabilities ranging from 60% to 90%, and greater catch variability observed in model-based MPs.

Carruthers (2024) introduces a streamlined simulation platform for Atlantic Blue Shark MSE, using operating models that incorporate uncertainty in life-history and productivity parameters. It evaluates both index- and model-based MPs, demonstrating that many exceed performance benchmarks such as maintaining biomass above 40% BMSY and achieving 60–90% probability of being in the Kobe green quadrant. The platform also explores algorithms to automatically tune MPs to minimum performance standards. The full source code is available at github.com/Blue-Matter/Blue_Shark_MSE.

The SCRS aims to submit a feasibility analysis for northern and southern Blue Shark MSE to the Commission by 2025.

Northeast Atlantic Porbeagle

Preliminary MSE Work

Although a formal Management Strategy Evaluation (MSE) process has not been established, closed-loop simulation techniques have been applied to evaluate the implications of various data and assessment model configurations on the performance of candidate management procedures for Northeast Atlantic porbeagle shark. In the absence of a consistent time series of relative abundance for the stock, such simulation-based analyses are particularly valuable for exploring alternative assessment and management approaches.

Preliminary MSE work for Northeast Atlantic porbeagle has focused on simulation testing, the definition of operational objectives, and the influence of data availability on yield and conservation performance. Initial simulations, presented in Taylor et al. (2022a), applied closed-loop testing to a range of simple empirical management procedures. These early trials revealed that management performance varied considerably across candidate procedures, particularly with respect to yield and the risk of stock depletion. The analyses followed the structured MSE framework outlined by Punt et al. (2016), incorporating operating model specification, objective setting, and evaluation of performance metrics.

A complementary document, Taylor et al. (2022b), proposed a set of management objectives, associated performance metrics, and graphical tools intended to support stakeholder engagement and transparent evaluation of candidate management procedures.

At present, no active MSE development is underway for Northeast Atlantic porbeagle shark.

References

Materials

Rec/Res

Meetings

SCRS Docs

Others

Updated: July 7, 2025

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