Ability of Unfed Dermacentor variabilis (Acari: Ixodidae) to Survive a Second Winter as Adults in Manitoba, Canada, Near the Northern Limit of Their Range.
One thousand seven hundred unfed field-collected adult Dermacentor variabilis (Say) were overwintered in 34 outdoor enclosures near the northern limit of their distribution in Manitoba, Canada. At the northern limits of the range of D. variabilis, it had always been assumed that unfed adult ticks questing in spring succumbed before the next winter and were not part of the population observed in the following year. Survival of the collected ticks was assessed on two occasions. In midwinter, an average 39.4% (SE ± 2.50) of the ticks were still alive, while an average 19.9% (SE ± 1.14) survived to April. Female ticks had significantly higher survivorship than males. The ability to survive an additional winter allows ticks to act in a greater capacity as reservoirs for tick-associated pathogens in this region.
Department of Entomology, University of Manitoba, Winnipeg, Manitoba, Canada R3T 2N2. Corresponding author, e-mail: matt.yunik@gmail.com.
Matthew E M
ME
Yunik
Department of Entomology, University of Manitoba, Winnipeg, Manitoba, Canada R3T 2N2.
Terry D
TD
Galloway
Department of Entomology, University of Manitoba, Winnipeg, Manitoba, Canada R3T 2N2. Public Health Agency of Canada, National Microbiology Laboratory, Winnipeg, Manitoba, Canada R3E 3R2.
L Robbin
LR
Lindsay
D000818:Animals; D001179:Arthropod Vectors / Q000502:physiology*; D003080:Cold Temperature; D003870:Dermacentor / Q000502:physiology*; D005260:Female; D008297:Male; D008350:Manitoba; D012621:Seasons
northern distribution limit; snow cover; vector potential; winter survival