Effects of the Herbicide Metolachlor and Pond Drying on Growth and Development of Wood Frog Tadpoles (Lithobates sylvaticus).

This article investigates the individual and combined effects of the herbicide metolachlor and varying pond drying rates on the growth, development, and survival of wood frog (Lithobates sylvaticus) tadpoles. Using a controlled mesocosm experiment with environmentally relevant metolachlor concentrations and simulated drying regimes, the study found that metolachlor alone did not significantly affect tadpole survival, development time, or body mass at metamorphosis. However, an interaction between intermediate metolachlor levels and rapid drying reduced tadpole growth rates, while drying independently decreased growth and body mass at metamorphosis without accelerating development. The findings highlight the importance of considering environmental stressors like pond drying, influenced by climate change, in ecotoxicological assessments of pesticide impacts on amphibians.