05
Dec
Fungicides Tied to Declining Bumblebee Populations in the United States
(Beyond Pesticides, December 5, 2017) Fungicides are likely playing an important role in the decline of North American bumblebee populations, according to new research published by a team at Cornell University. While overwhelming data continue to indicate that insecticides, particularly the neonicotinoid class of chemicals, are the leading factor in overall pollinator declines, Cornell scientists discovered that fungicides, in particular the chemical chlorothalonil, are likely compounding risk and toxicity for U.S. bumblebee species. As new studies continue to expand the chemical culprits in pollinator declines, calls for a wholesale change in agricultural practices toward more sustainable organic production are reinforced. Cornell researchers began their investigation by focusing on what land use factors had the most impact on eight bumblebee species, many of which have been declining in the U.S. Bumblebee species were sampled at nearly 300 sites in 40 states during the summer months, and at each of the sampling sites, landscape variables were characterized and quantified for land use (urban v rural), habitat (high vs low latitude), and pesticide (insecticide, fungicide, herbicide) usage. The strongest indicator of declining range within the selected bumblebee species was found to be overall fungicide use, with those in the northern U.S. undergoing the […]