The objective of the EFIMAS project is to develop an operational management evaluation framework that allows evaluation of the trade-off between different management objectives when choosing between different management options.

The evaluation framework will be developed to inform an exploratory, adaptive decision- making process.

Evaluation tools will be developed to appraise the biological, social and economic effects of fisheries management measures in the EU, and these will be applied to important fisheries. The tools will take account of the dynamics in the fisheries systems, as well as of uncertainties and will include risk assessments.


The overall approach uses stochastic simulation techniques. These cover the full scope of the fisheries system from the fish resources, through data collection, assessment and management, and the response of the system to management.

The input data to the management system are generated by a descriptive model, which is assumed to represent the "true/real" system. The input data are then processed by a traditional assessment model, or by an alternative model, which is used to generate management advice.

By simulating the effect that the resultant management actions would have on the "true/real" system it is possible to generate a range of performance measures, covering the resource and the fishery. These measures can then be compared across different assessment models and management approaches.


To give an example, a change from stock-based to fleet-based management represents a change in paradigm of fisheries management. Such a change allows advice to be given in the form of effort limits, and accounts for technical interactions and also involves economic and social parameters.

In this case the evaluation tools simulate both stock-structured input data and fleet-structured input data; it performs the traditional assessment with stock-structured data and alternative assessment with fleet structured data. Replicate runs including stochastic variation can be used to estimate probability distributions of the performance measures of the two alternative management scenarios so that their performance can be compared.

Tool Development

The operational evaluation tools have been developed in parallel with an evaluation of their utility in informing a decision making process and will be modified according to experiences from their use by stakeholders.

The tools have been implemented in a range of case studies including important European demersal, deep-sea and pelagic fisheries and have been modified on the basis of experiences from case implementation.

27 MARCH 2023