Commercially traded fish portfolios mask household utilization of biodiversity in wild food systems

Abstract

The global biodiversity that underpins wild food systems—including fisheries—is rapidly declining. Yet, we often have only a limited understanding of how households use and benefit from biodiversity in the ecosystems surrounding them. Explicating these relationships is critical to forestall and mitigate the effects of biodiversity declines on food and nutrition security. Here, we quantify how biodiversity filters from ecosystems to household harvest, consumption, and sale, and how ecological traits and household characteristics shape these relationships. We used a unique, integrated ecological (40 sites, quarterly data collection) and household survey (n = 414, every 2 mo data collection) dataset collected over 3 y in rice field fisheries surrounding Cambodia’s Tonlé Sap, one of Earth’s most productive and diverse freshwater systems. While ecosystem biodiversity was positively associated with household catch, consumption, and sold biodiversity, households consumed an average of 43% of the species present in the ecosystem and sold only 9%. Larger, less nutritious, and more common species were disproportionally represented in portfolios of commercially traded species, while consumed species mirrored catches. The relationship between ecosystem and consumed biodiversity was remarkably consistent across variation in household fishing effort, demographics, and distance to nearest markets. Poorer households also consumed more species, underscoring how wild food systems may most benefit the vulnerable. Our findings amplify concerns about the impacts of biodiversity loss on our global food systems and highlight that utilization of biodiversity for consumption may far exceed what is commercially traded.