posted on 2022-01-20, 13:42authored byStacey Adele Robinson, Sarah D Richardson, Rebecca L Dalton, France Maisonneuve, Adrienne Bartlett, Shane R de Solla, Vance L. Trudeau, Nigel Waltho
Neonicotinoid insecticides are used extensively in agriculture and as a consequence, are now detectable in nearby aquatic environments. Few studies have evaluated the effects of neonicotinoids on amphibians in these aquatic environments. In this present study, we examined the effects of two commercial formulations of neonicotinoids (active ingredients clothianidin and thiamethoxam) on survival and life-history traits of wood frogs (Lithobates sylvaticus) and northern leopard frogs (Lithobates pipiens). We used artificial pond mesocosms to assess the effects of these neonicotinoids, at nominal concentrations of 2.5 µg/L and 250 µg/L, on amphibian larval development through metamorphosis. We found no differences between controls and neonicotinoid exposure for any of the endpoints assessed for either wood frogs or leopard frogs. Our study suggests that concentrations meeting or exceeding observed levels of clothianidin and thiamethoxam in surface waters will not directly affect metamorphosis in two amphibians.