Fungal pathogen in US bumble bees

An analysis of fungal DNA collected from North American Bombus bumble bee museum specimens finds that the presence of a native strain of Nosema bombi, the fungal pathogen linked with bumble bee declines, increased in declining wild Bombus populations during the early- to mid-1990s concurrent with N. bombioutbreaks in reared Bombus, suggesting potential pathogen transmission from commercial to wild bees but failing to find conclusive proof that a European strain entered North America. - See at PNAS.org

Article #15-25266: “Test of the invasive pathogen hypothesis of bumble bee decline in North America,” by Sydney A. Cameron, Haw Chuan Lim, Jeffrey D. Lozier, Michelle A. Duennes, and Robbin Thorp.