ICCAT 2016: Implementing Harvest Strategies in Tuna Fisheries via Management Strategy Evaluations

By Holly Koehler and Dr. Victor Restrepo

11 November 2016

Holly Koehler and Victor Restrepo

In recent years in the fisheries and sustainability communities, we’ve been working on the need to adopt harvest strategies (a.k.a. management procedures) or harvest control rules (HCRs) through the implementation of Management Strategy Evaluations (MSE) at tuna RFMOs. Most RFMOs have started processes to promote dialogue between scientists and managers to increase understanding and comfort with these concepts, but progress is still fairly slow. There are understandable reasons for the cautious pace at RFMOs: These are a set of complicated concepts that are still new to many in the tuna realm.

When faced with a complicated problem, it’s best to break it down into pieces or steps, while keeping in mind that at some point all of the pieces will come together.

Harvest strategies (also known as “Management Procedures”) are an essential tool for modern and precautionary fisheries management. The evidence of success from fisheries where harvest strategies have been implemented is clear — not only do harvest strategies provide a strong platform to rebuild stocks that have been subject to overfishing, they also allow greater understanding of cumulative effects of management decisions and the impact of uncertainty. And governments and industry can plan for the long term.

Harvest strategies have three core components:

  1. Monitoring (e.g., what data to be used)
  2. Assessment (e.g., CPUE standardization or production models)
  3. A harvest control rule (HCR)

An MSE is a strategic tool for testing and comparing alternative harvest strategies to determine which is the best or most likely to meet the management objectives for the fishery, and to understand tradeoffs between different objectives. Implementing an MSE is complicated. It takes time because specific goals and objectives must be identified; conceptual models must be developed, evaluated and tested through computer simulation. This last step involves many rounds of feedback between managers and scientists, and refinement can take years.

Two RFMOs — IOTC and IATTC — have adopted an HCR without completing an MSE process first. Yes, it can be done. But this approach is a bit like deciding what car you will buy before fully evaluating the features of different models with your current and future needs in mind. If you are looking to establish a management strategy that meets objectives in the long term — or have a car that fits with your planned lifestyle or family size — you must test drive it first. So it goes with HCR; this is what MSE is all about. It allows fisheries managers and scientists to examine the relative performance and trade-offs across alternatives, testing different scenarios, and identifying monitoring and implementation priorities.

RFMOs are grappling with MSE to develop and test harvest strategies, and some may see this as unwarranted delay, or a negotiating tactic. We must keep in mind, however, that for managers, it is often a challenge to agree on specific components needed for MSE — such as management objectives and reference points — without knowing what the future consequences will be, and without a deep understanding of the flexibility inherent in the MSE process. In addition, RFMOs work on a yearly cycle and have limited time for detailed discussion on these kinds of topics. While technical workshops are happening, time and resources are at a premium.

Have you ever heard the phrase, “Nothing is agreed until everything is agreed?” This is an important maxim to keep in mind as we work with the RFMOs to implement harvest strategies through MSE. At present, MSE elements are often discussed separately  reference points, management objectives, acceptable levels of risk, HCR — and managers who do not have a clear understanding of how these work together with possible management strategies as a package can be hesitant to approve them one by one.

Taking complex concepts and breaking them down to understand how the pieces all work together is a key to success. To return to the example of buying a car: You would not buy each component individually — the hood, the seats, the engine — to build your “perfect” car. Rather, you identify a package of elements that are desirable, and test drive different cars before selecting the one that best meets your needs and objectives. MSE is the same idea — there are many ways to develop harvest strategies, but they all need dialogue, work, and patience to develop.

WATCH: Additional resources

Susan Jackson, President, ISSF; Dr. William Fox, Vice President of Fisheries, WWF-US; Dr. Victor Restrepo, Chair, ISSF Scientific Advisory Committee; and Dr. Gerald Scott, ISSF Scientific Advisory Committee, discuss implementation of harvest control rules and why RFMOs should adopt them.
Click here to view the video

Dr. Victor Restrepo, Chair of ISSF’s Scientific Advisory Committee, discusses the precautionary principle versus the precautionary approach in relation to tuna management.
Click here to watch the video

ISSF Scientific Advisory Committee member Dr. Gerald Scott discusses tuna fishery management options, and the use of input and output controls.
Click here to watch the video