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bioRxiv · 10.1101/2019.12.11.873042

Larval thermal characteristics of multiple ixodid ticks underlie their range dynamics

Fieler, A.·Rosendale, A.·Farrow, D.·Dunlevy, M.·Davies, B.·Oyen, K.·Benoit, J.
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Abstract

Temperature is a major factor that impacts tick populations by limiting geographic range of different species. Little is known about the thermal characteristics of these pests outside of a few studies on survival related to thermal tolerance. In this study, thermal tolerance limits, thermal preference, impact of temperature on metabolic rate, and temperature-activity dynamics were examined in larvae for six species of ixodid ticks. Tolerance of low temperatures ranged from -15 to -24{degrees}C with Dermacentor andersoni surviving at the lowest temperatures. High temperature survival ranged from 41 to 47 {degrees}C, with Rhipicephalus sanguineus having the highest upper lethal limit. Ixodes scapularis showed the lowest survival at both low and high temperatures. Thermal preference temperatures were tested from 0-41{degrees}C. D. variabilis exhibited a significant distribution of individuals in the lower temperatures, while the majority of other species gathered around 20-30{degrees}C. Activity was measured from 10-60{degrees}C, and the highest activity was observed in most species was near 30{degrees}C. Metabolic rate was the highest for most species around 40{degrees}C. Both activity and metabolic rate dropped dramatically at temperatures below 10{degrees}C and above 50{degrees}C. In summary, tick species vary greatly in their thermal characteristics, and our results will be critical to predict distribution of these ectoparasites with changing climates.

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Fieler, A., Rosendale, A., Farrow, D., Dunlevy, M., Davies, B., Oyen, K., Benoit, J.. 2019-12-12. Larval thermal characteristics of multiple ixodid ticks underlie their range dynamics. https://doi.org/10.1101/2019.12.11.873042

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