Drawing the line between sustainable and unsustainable fish: product differentiation that supports sustainable development through trade measures.

Background: Unsustainable production practices and increased demand for fish have aggravated negative social, ecological, and environmental impacts in fisheries and aquaculture. Measures to correct bad practices have mainly been introduced by private actors. However, there is increased demand for state intervention, particularly regarding trade regulations for fish and other agricultural products. Building on discussions about product differentiation through trade measures that favour sustainable products, this study looked at how sustainable and unsustainable fish has been distinguished in Switzerland. In interviewing experts in the fish trade and sales business in Switzerland, the research aimed at understanding the actors and forces that shape the concept of sustainable fish in the country.

Results: Three ways of product differentiation for sustainable fish by private actors were identified in Switzerland: ecolabels, "Swiss produce", and recommendations in the form of a "consumer guide for fish". Currently, price is the main constraint on consumption of sustainable products in the country. Defining "sustainable fish" is challenging and subject to interpretation. All existing measures to differentiate sustainable from unsustainable fish products in Switzerland have shortcomings, particularly in terms of discrimination and inclusiveness. Fish ecolabels play a key role in product differentiation, but experts believe that they fail to accommodate all aspects of sustainability.

Conclusion: Our findings imply that the Swiss state should play a more important role if it aims to fulfil the promise of article 104a of the Swiss Constitution, which seeks to foster sustainable production and cross-border trade relations that contribute towards this goal. Preferred trade treatment for sustainable fish products is a potential option to increase the production and consumption of sustainable fish. When designing measures for product differentiation, a careful choice is paramount to address sustainability in a holistic, inclusive, and transparent way and in order not to violate existing trade obligations. Due to similarities between the Swiss and other fish markets, we assume that governments in general and members of the European Union in particular must play an active role in shaping the definition and trade of sustainable fish products if they seek to comply with their sustainability commitments.

Supplementary Information: The online version contains supplementary material available at 10.1186/s12302-021-00551-6.