Water pollution from swine factory farms poses a threat to endangered and threatened species

Abstract

Factory farms, or concentrated animal feeding operations (CAFOs), generate millions of tons of manure each year in the United States. The storage, handling, and land application of this manure leads to air, water, and climate pollution, which disproportionately impacts low‐income communities of color and poses additional public health and environmental justice concerns. Furthermore, these operations threaten biodiversity, including through the contamination of surrounding waterways, which can impact aquatic species' physiology, development, and reproduction. To identify aquatic species most likely to be impacted by pollution from CAFOs, we analyzed geographic overlap between federally listed endangered and threatened species' ranges and CAFO locations in Iowa, North Carolina, and Minnesota, which are the three states with the highest inventories of swine. We identified 17 aquatic species that are endangered, threatened, or under review for listing—including mussels, fishes, a snail, and an amphibian—with habitat ranges that overlap with swine CAFOs. Among these, 10 species have designated critical habitat located in watersheds that contain swine CAFOs. Additionally, we identified hundreds of watersheds in which CAFOs are hydrologically connected to listed species' ranges, in some cases with millions of tons of manure generated by swine CAFOs at the watershed‐scale each year. Our findings suggest that water pollution and other environmental impacts from swine CAFOs represent a potential threat to endangered and threatened species. Improved regulation of water pollution from swine CAFOs will be necessary to reduce these threats to biodiversity.