Independent Science News has just published: New Research Links Neonicotinoid Pesticides to Monarch Butterfly Declines by Jonathan Latham, PhD
Article synopsis: New research has identified the neonicotinoid insecticide clothianidin as a likely contributor to monarch butterfly declines in North America. The research, published on April 3rd 2015, identifies concentrations of clothianidin as low as 1 part per billion as harmful to monarch butterfly caterpillars. These concentrations of clothianidin were found on naturally growing milkweeds sampled by the researchers. The research was conducted in near maize fields in Brookings, South Dakota
Previously, no research had been done on neonicotinoids and butterflies and therefore this is the first published report of neonicotinoids affecting monarchs or any other butterflies. It was published in the journal Science and Nature (Springer).
Pencenka JR and JG Lundgren (2015) Non-target effects of clothianidin on monarch butterflies Sci Nat 102:19.
Access to research demonstrating harmful effects of neonicotinoids on various beneficial insects: http://www.entomology.umn.edu/faculty-staff/vera-krischik