Temporal coincidence of amphibian migration and pesticide applications on arable fields in spring
2015
Lenhardt, Patrick P. | Brühl, Carsten A. | Berger, Gert
Pesticide management may differ between crop species and farm type, particularly with regard to type, number, amount and date of pesticide applications. Such variations in pesticide application strategies entail different temporal coincidence with amphibian species and with species’ population proportions. For the first time, we assessed the presence of Bombina bombina, Rana arvalis, Pelobates fuscus and Triturus cristatus in agricultural fields. We quantified the temporal coincidence of pesticide applications with the breeding migrations of adult amphibians and evaluated a realistic exposure to pesticides, including the interception by various crops at different growth stages. The level of species-specific coincidence depended on the performed pesticide management, determined by the timing, crop, number and type of pesticide applications. Late migrating species, such as B. bombina and P. fuscus, overlapped more with pesticide applications than early migrating species, such as R. arvalis. Up to 86% of the reproducing population proportion of P. fuscus experienced a temporal coincidence with a single pesticide application during stem elongation in winter rape (80% interception). In maize, up to 17% of the reproducing population proportion of B. bombina encountered a single herbicide application during bare soil/emergence (no interception). Local monitoring of amphibian migration combined with adjusted pesticide management is recommended to reduce temporal coincidence and thus potential risk of pesticide exposure of amphibians.
显示更多 [+] 显示较少 [-]