The recent report by McKinsey and Company 'Design for Sustainable Fisheries' takes some important steps towards meeting the challenge of integrating what we understand about the biology of fished species and the economic behaviour of those who fish. It is vital that we do this if we are to better understand the complexities that drive changes in human pressure on fish stocks and how these stocks respond.

While transitioning to sustainable fisheries is crucial, there are at least three root causes that explain why it is so challenging. First, since achieving sustainable fishing typically requires a reduction in fishing effort and changes in fishing practices for some period of time, there are usually short-term financial losses throughout the value chain.

Those players who — often for subsistence reasons resulting from a lack of alternative opportunities — place a higher value on short-term benefits may be less concerned about driving a fishery to collapse than about losing shortterm harvests. Second, even when a fishery reaches a sustainable state, its economic and other benefits may not be evenly distributed among different players: in many cases fishery restoration creates winners and losers as some players will benefit from the long-term solution and others will carry an increased burden as a result of more sustainable practices. Third, data gathering and adequate fishery management are usually necessary to achieve sustainable fishing, however in many areas these are difficult to put into action .

Without an indication of the health of the fish stock, even the fishers with the best intentions can overfish since they do not know when they are overfishing. Ineffective management of global fisheries is likely to result in the depletion of the shared resource, meaning unrecoverable ecological and economic losses.

To help address these challenges, we devised a methodology that can compare both the biological and economic impact of the different choices available for managing the different fisheries of the world.

We collaborated with leading fishery experts from UC Santa Barbara and Eco-Analytics group to carry out the underlying biological modeling, and we led the overall analysis and contributed to the economic modeling for the bio-economic model. To illustrate the methodology and see how the model can provide a clear understanding of transition options to help stakeholders in their efforts to establish sustainable fisheries, we examined three fisheries in detail.

In each case outlined below, detailed field research was conducted to understand both the specific stakeholders concerned and the value chain dynamics. Using in-depth biological and economic modeling, we explored different potential future management scenarios, starting with a Business as Usual (BAU) scenario and comparing it with different transition paths to a sustainable state. By analyzing these scenarios, we could highlight the significantly different biological and economic outcomes.

The study of the bluefin tuna (BFT) in the East Atlantic and Mediterranean provides an example of a fishery that is on the verge of collapse due to the species’ high level of biological vulnerability, overfishing, and Illegal, Unreported, and Unregulated (IUU) fishing. We modeled three different scenarios: one in which current practices continue, a second where IUU fishing is eliminated, and a third where the fishery is closed completely to allow recovery.

The first sees the collapse of the fishery within the next 2–5 years, along with the industry’s profits. The second and third both return the bluefin tuna fishery to a sustainable path. Closure of the fishery brings about the fastest and most assured recovery of the bluefin tuna, but would be the most economically challenging transition path in the short term as both fishers and tuna ranches would see significant losses.

The Gulf of Mexico red snapper case study provides an example of a fishery that has implemented an Individual Fishing Quota (IFQ) for its commercial sector and is on the road to recovery. But the speed of recovery and potential economic benefits are impeded by overfishing and dead discards in the recreational sector.

The analysis examined five different scenarios, ranging from Business as Usual (BAU), to reducing the number of dead discards, and a combination of fewer discards and adherence to the Total Allowable Catch (TAC) limit imposed by the Gulf of Mexico Fishery Management Council (GMFMC).

This target was set with the goal of reaching sustainability by 2032. The analysis showed that BAU would mean failing to meet the 2032 sustainability target. Full adherence to the TAC by all players and a 60 percent decline in the discard mortality rate could see the fishery reach sustainability in just five years, with all players benefiting.

The third study is hypothetical due to lack of comprehensive biological and economic data on a tropical fishery. The case looks at a tropical grouper fishery using the biological characteristics of grouper and making assumptions on fishing practices based on data from a variety of fisheries in the Coral Triangle.

In this hypothetical case, the fishery starts in a relatively pristine state. However, a combination of overfishing and destructive fishing practices — due to a lack of management and appropriate incentives throughout the value chain — is driving the fishery and the eco-system to collapse. We looked at three different scenarios. The first assumes BAU, with only artisanal fishers fishing the waters.

Nevertheless, the fishery collapses by 2029. The second models the entry of large-scale operators, which accelerates the collapse and sees short-term profits of local fishers halved within five years. The third excludes large-scale operators from tropical grouper fisheries at the same time as constraining harvests by artisanal fishers, helping the grouper fisheries return to economic and biological sustainability by eliminating destructive practices (such as the use of toxic chemicals) and maintaining fishing at a sustainable level. Under this scenario, profits for artisanal fishers are maximized in the longterm (20 years).

All three case studies had a number of issues that many fisheries have in common, including lack of data, IUU, overcapacity, and lack of ownership incentives.

Three key insights arose, which can guide the future evolution of the methodology and its application in the context of fisheries management.

First, stakeholder dynamics and root causes of key issues within specific fisheries are not always obvious and both in-depth field research and economic modeling are required to understand them.

Second, there are many different pathways to achieving the biological objective of sustainability, and modeling can help in: (1) providing a holistic view of the winners and losers in the value chain during a transition; (2) comparing the biological and economic impact of different transition pathways; and (3) identifying new management solutions with the smallest burden on the involved players.

Finally, to perform the economic analysis and construct the most effective solutions, a variety of experts need to be engaged in the debate— biologists, NGOs, fishery managers, government, multilateral agencies, valuechain players, and others— who all bring different insights into the dynamics of a fishery.

Further Reading

- You can view the full report by clicking here.

Lucy Towers

Learn more