Glyphosate applications on arable fields considerably coincide with migrating amphibians

Area of Science:

• Environmental Toxicology
• Ecology
• Herbicides

Background:

• Global glyphosate use is increasing, with evolving application strategies.
• Amphibians migrating through agricultural landscapes face potential harm from herbicide exposure.

Purpose of the Study:

• To investigate the temporal coincidence between amphibian populations and glyphosate application.
• To assess the risk posed by glyphosate exposure during terrestrial life stages of amphibians.

Main Methods:

• Analysis of population-based temporal coincidence of four amphibian species with glyphosate application from 2006 to 2008.
• Consideration of species-specific migration periods, crop types, glyphosate application methods, and glyphosate's persistence (DT50).

Main Results:

• Calculated up to 100% temporal coincidence between amphibians and glyphosate applications.
• Observed regular co-occurrence with pre-sowing/pre-emerging glyphosate applications to maize and stubble management.
• Siccation treatment in summer showed coincidence only with early-stage juveniles.

Conclusions:

• Glyphosate applications, particularly pre-sowing and stubble management, pose a significant temporal risk to migrating amphibians.
• Further research is crucial to understand both acute and long-term effects of glyphosate on amphibians during their terrestrial phases.