The expanding geographic ranges of tick species that are known pathogen vectors 
can have implications for human, domestic animal, and wildlife health. Although 
Alaska is home to several hard tick species, it has historically been outside of 
the range of the most common medically important ticks in the contiguous United 
States and western Canada. To assess the status of tick species establishment in 
the state and to provide a baseline for tracking future change in the 
distribution of ticks, we reviewed and compiled historical tick records and 
summarized recent tick occurrence records collected through the development of 
the Alaska Submit-A-Tick Program and through tick drag sampling at sentinel 
sites in southcentral Alaska. Between 1909-2019, there were 1190 tick records 
representing 4588 individual ticks across 15 species in Alaska. The majority of 
ticks were species historically found in Alaska: Haemaphysalis leporispalustris, 
Ixodes angustus, Ixodes auritulus, Ixodes howelli, Ixodes signatus, and Ixodes 
uriae. Over half of all tick records in the state were collected in the last 
10 yr. During this time, the number of tick records and the number of tick 
species recorded in Alaska each year has increased substantially. Between 
2010-2019, there were 611 tick records representing 1921 individual ticks. The 
most common hosts for reported ticks were domestic animals (n = 343, 56 %) 
followed by small wild mammals (n = 147, 24 %), humans (n = 49, 8%), and wild 
birds (n = 31, 5%). Less than 5% of records (n = 25) were of unattached ticks 
found in the environment. Since 2007, non-native tick species have been 
documented in the state every year, including Amblyomma americanum, Dermacentor 
andersoni, Dermacentor occidentalis, Dermacentor variabilis, Ixodes pacificus, 
Ixodes ricinus, Ixodes scapularis, Ixodes texanus, and Rhipicephalus sanguineus 
sensu lato (s.l.). Almost half of the records (n = 68, 48 %) of non-native tick 
species from 2010 to 2019 represented ticks found on a host (usually a dog or a 
human) that had traveled outside of Alaska in the two weeks prior to collection. 
However, A. americanum, D. variabilis, I. pacificus, I. texanus, and R. 
sanguineus s.l. have been found on humans and domestic animals in Alaska without 
reported recent travel. In particular, there is evidence to suggest that there 
is local establishment of R. sanguineus s.l. in Alaska. A tick species 
historically found in the state, I. angustus was frequently found on human and 
dogs, suggesting a potential role as a bridge vector of pathogens. Given the 
inconsistency of tick monitoring in Alaska over the past century, it is 
difficult to draw many conclusions from temporal trends in the data. Continued 
monitoring through the Alaska Submit-A-Tick Program will allow a more accurate 
assessment of the changing risk of ticks and tick-borne diseases in the state 
and provide information for setting clinical and public health guidelines for 
tick-borne disease prevention.