Bird species potentially exposed to pesticide-treated corn seeds in the continental United States.

In the United States, the use of pesticide-coated seeds in agriculture is a widely adopted practice. Consumption of treated crop seeds is a possible route of exposure of birds to pesticides. A combination of agronomic and bird life history information is used to identify those species most likely to consume freshly planted corn seeds. Species listed as threatened or endangered by the US Fish and Wildlife Service that could consume treated seeds are also identified. Corn-growing counties in the continental United States were compiled for the years 2017-2020. Seven hundred and eight bird species occur in corn-growing counties. Feeding habits and habitats of North American bird species that occur in corn-growing counties indicate that 107 species could feed on the ground in or adjacent to freshly planted corn fields and consume seeds. Of these, 21 species show a high tendency to feed in or around freshly planted corn fields and could consume a large quantity of corn seeds. Of the 107 species with the potential to consume freshly planted corn, only two full species (as opposed to subspecies), the Gunnison sage-grouse and whooping crane, are listed as threatened or endangered under the US Endangered Species Act. Additionally, two subspecies, Mississippi sandhill crane and masked bobwhite, are listed as endangered. The streaked horned lark is listed as threatened. Of the 21 species, including subspecies, that have the greatest potential to consume a freshly planted treated corn seed, the Mississippi sandhill crane is the only listed species considered to have a high potential to consume treated corn seeds. Therefore, the potential exposure of federally listed threatened or endangered bird species to pesticides through the direct consumption of pesticide-treated corn seeds is low, with the possible exception of the Mississippi sandhill crane. Integr Environ Assess Manag 2023;19:461-473. © 2022 SETAC.