Do ticks exhibit repeatable individual behaviors?

Area of Science:

• Ecology
• Behavioral Biology
• Epidemiology

Background:

• Tick-borne diseases are often modeled using population-level epidemiological factors.
• Individual tick behavior at the host-vector interface is less understood.
• Investigating individual tick agency could offer new insights into disease transmission dynamics.

Purpose of the Study:

• To determine if adult Dermacentor andersoni and D. variabilis ticks exhibit repeatable individual behaviors.
• To assess if these behaviors are consistent across different experimental conditions and over time.
• To understand the implications of individual tick behavior for disease transmission.

Main Methods:

• Conducted four experiments on adult D. andersoni and D. variabilis ticks.
• Tested behaviors including directional movement, CO2 attraction, phototaxis, and repellent avoidance.
• Repeated experiments across two distinct field seasons (2021 and 2022) at the same collection site.

Main Results:

• In 2021, individual ticks demonstrated repeatable behaviors within and across experiments, suggesting consistent behavioral traits.
• This evidence of trait-like behavior was not observed when experiments were repeated in 2022.
• A significant heat wave in 2021 impacted tick species composition at the study site.

Conclusions:

• Repeatable, individual tick behaviors influencing disease transmission were detected in one season but not the subsequent one.
• Multiyear studies are crucial for accurately assessing the consistency and significance of individual behaviors in ectoparasites.
• Environmental factors, such as extreme weather events, can influence tick populations and potentially mask behavioral patterns.