Blacklegged Tick Population by Migratory Birds in Ontario, Canada
Researchers have discovered a new Lyme disease endemic area in Frontenac County that was likely started by spring migratory songbirds. This remote site, near Verona, Ontario, is located a considerable distance from roads and dwellings, which indicates that songbirds introduced immature (larva, nymphs) blacklegged ticks, the primary vector of the Lyme disease bacterium, Borrelia burgdorferi. This established population of blacklegged ticks was studied over a 2-year period, and the infection rate, using PCR testing, averaged 33.3% for B. burgdorferi.
White-tailed deer are common in this woodland area; however, they do not act as competent reservoirs of B. burgdorferi and, consequently, are not as a source of infection for the ticks. Because of the limited source of B. burgdorferi infection, we suggest that songbirds most likely imported Lyme-carrying blacklegged ticks to this remote locale.
During spring migration, millions of northward-bound songbirds disperse Lyme disease-infected ticks across southern Canada. Throughout the breeding and nesting season, songbirds typically distribute larval and nymphal Lyme disease-carrying blacklegged ticks locally throughout the surrounding area. Therefore, people do not have to frequent an endemic area to contract Lyme disease.
Our research reveals that songbirds are involved in the establishment of blacklegged tick populations in eastern and central Canada.
This tick research was conducted by J. D. Scott, C. M. Scott, Research Division, Lyme Disease Association of Ontario, and J. F. Anderson, Department of Entomology and Center for Vector Biology and Zoonotic Diseases, The Connecticut Agricultural Experiment Station. It was published in the Journal of Veterinary Science and Medicine, Open Access, online: http://www.avensonline.org/medical/veterinary-science-medicine/articles-in-press-11/ Read full text here.
For more information, contact: John D. Scott, M.Sc.
519-843-3646 (before 4:00 p.m., DST)