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Rocky Mountain wood tick

Dermacentor andersoni

Identification

This tick has a similar appearance to the American dog tick, but it’s distinguishable by its bright red body, which is shaped like a teardrop. Females have a white-colored shield. Males have gray and white spots on their body.9

Nymph

Male

Female

Engorged Female

Approximate Distribution

As the name suggests, the Rocky Mountain wood tick is found in the Rocky Mountain states in an area from eastern California to eastern Colorado and north to the Canadian border.10

Hosts


The Rocky Mountain wood tick is a three-host tick, meaning its preferred host depends on the stage of its life cycle. Larvae and nymphs feed on small mammals like voles, mice, and squirrels. Adults prefer larger mammals like raccoons, dogs, white-tailed deer, and cattle.11

Habitat

Rocky Mountain wood ticks are found in grasslands, shrublands, lightly wooded areas, and along trails.12

Diseases associated with Dermacentor andersoni20, 21

References:

9. Rocky Mountain Wood Tick. Tick Research Lab of Pennsylvania. https://www.ticklab.org/rocky-mountain-wood-tick
10. Approximate Distribution of the Rocky Mountain Wood Tick. Centers for Disease Control. https://www.cdc.gov/ticks/maps/rocky_mountain_wood_tick.pdf
11. Interspecific Differences in the Questing Behaviour of Dermacentor Andersoni and Dermacentor Variabilis (Acari: Ixodidae) larvae. The Canadian Entomologist. https://www.cambridge.org/core/journals/canadian-entomologist/article/interspecific-differences-in-the-questing-behaviour-of-dermacentor-andersoni-and-dermacentor-variabilis-acari-ixodidae-larvae/B23379F523B9B7F2A319D3957D6FDFE0
12. Rocky Mountain Wood Tick. University of Rhode Island. https://web.uri.edu/tickencounter/species/rocky-mountain-wood-tick/
20. Ticks. Companion Animal Parasite Council. https://capcvet.org/guidelines/ticks/
21. Ticks. Companion Animal Parasite Council. https://capcvet.org/guidelines/ticks/