Climate change influences on the geographic distributional potential of the spotted fever vectors and .

(Gulf Coast tick), and (Rocky Mountain wood tick) are two North American ticks that transmit spotted fevers associated . transmits and , while transmits , , (Colorado tick fever virus), and . Increases in temperature causes mild winters and more extreme dry periods during summers, which will affect tick populations in unknown ways. Here, we used ecological niche modeling (ENM) to assess the potential geographic distributions of these two medically important vector species in North America under current condition and then transfer those models to the future under different future climate scenarios with special interest in highlighting new potential expansion areas. Current model predictions for showed suitable areas across the southern and Midwest United States, and east coast, western and southern Mexico. For , our models showed broad suitable areas across northwestern United States. New potential for range expansions was anticipated for both tick species northward in response to climate change, extending across the Midwest and New England for , and still farther north into Canada for .