Movement capabilities of Amblyomma americanum in laboratory and field conditions

Estimates of tick abundance and distribution are used to determine risk of tick bites. Surveillance is reliable for species that remain stationary, but some ticks, like  Amblyomma americanum, are highly mobile. Management of A. americanum is impeded because it is unknown what factors control tick distribution. To accurately assess risk of A. americanum-associated disease and identify avenues for tick control, it is critical to determine what factors affect where A. americanum will be encountered. Using mark-recapture techniques and video tracking software, we measured the distance A. americanum adults travel and how long they remain active in the field and laboratory. We measured the effect of tick abundance on the number of recaptured marked ticks. We found that ticks travel up to 9 m in the field and 360 m in the laboratory in 24-hours. Marked ticks were detectable for up to 14 days after release, but our results disagree as to the significance of time on recaptured ticks. The number of recaptures significantly increased with the relative abundance of ticks and single ticks were detectable one third of the time. Our results demonstrate that CO₂-baited traps are an effective means of sampling A. americanum, but many ticks remain unaccounted for in the environment. Lone star ticks are capable of navigating towards hosts over large distances, remain responsive to host cues for several weeks, and may pose a health risk even in very low numbers.