When do ticks lose activity?

When do ticks lose activity? - briefly

Ticks stop questing when temperatures fall to about 5‑10 °C (41‑50 °F) and relative humidity drops below roughly 70 %. Under such conditions they enter a dormant state.

When do ticks lose activity? - in detail

Ticks remain active only within specific environmental windows. Their locomotion, questing behavior, and host‑seeking are governed by temperature, humidity, photoperiod, and physiological status.

Temperature is the primary driver. Most species cease questing when ambient temperature falls below 5 °C (41 °F). Activity resumes as temperatures rise above 7–10 °C (45–50 °F), depending on species and life stage. Above 30 °C (86 °F) activity may also decline because excessive heat accelerates desiccation.

Relative humidity must stay above 80 % for successful questing. When humidity drops beneath 70 %, ticks withdraw into the leaf litter or soil to avoid dehydration. Prolonged periods of low moisture can interrupt feeding cycles and delay molting.

Day length influences seasonal patterns. Shortening photoperiod in autumn triggers diapause in many ixodid species, causing a shift from active questing to a dormant state that can last through winter.

Physiological factors also limit activity. After engorgement, females enter a reproductive phase and cease seeking hosts. Nymphs and larvae that have completed a blood meal will molt before resuming questing.

Typical conditions that induce inactivity:

  • Temperatures < 5 °C (41 °F) for more than 24 h
  • Relative humidity < 70 % sustained for several hours
  • Photoperiod ≤ 10 h daylight per day (autumnal cue)
  • Post‑engorgement reproductive phase in adult females
  • Completion of a developmental stage pending molt

Understanding these thresholds helps predict periods when tick populations are unlikely to bite, informing public‑health advisories and control measures.