Monarch butterfly and carbamates

This study investigated the impact of carbamate insecticides on the survival and development of monarch butterfly larvae (Danaus plexippus) across different life stages. Through controlled experiments, varying doses of carbamate insecticide (FURADAN ®) were administered to larvae, and their survival rates and morphological abnormalities. The results revealed that higher doses of carbamate insecticide led to a significant reduction in larval survival, particularly in stages LIII and LV, where survival rates dropped by 50-100% at a dose of 30 g/L. Additionally, larvae exposed to higher doses exhibited a higher prevalence of morphological malformations during development, attributed to the inhibitory action of carbamate insecticides on acetylcholinesterase (AChE). Despite the adverse effects observed, certain larval stages demonstrated resilience, possibly due to metabolic resistance mechanisms acquired from feeding on host plants containing cardiac glycosides. The study evidence the importance of understanding the differential impacts of insecticide exposure on monarch butterfly populations and highlights the need for targeted conservation strategies and environmentally sound policies to mitigate insecticide-related risks to this iconic species.