When does the tick season start and when does it end? - briefly
In most temperate regions, tick activity begins in early spring (March–April) and continues until late autumn (October–early November).
When does the tick season start and when does it end? - in detail
Ticks become active when ambient temperatures consistently exceed 7 °C (45 °F) and relative humidity remains above 80 %. This biological threshold defines the onset of the activity period for most species in temperate zones.
In the Northern Hemisphere, the activity period usually begins in early spring. Typical start dates are:
- Southern United States: late February to early March
- Mid‑Atlantic and Midwest: early to mid‑April
- Northeastern United States and southern Canada: late April to early May
In the Southern Hemisphere, the period commences during the local spring, roughly September to November, depending on latitude and altitude.
The activity period ends when temperatures drop below the 7 °C threshold for an extended interval, often accompanied by reduced daylight. Approximate end dates are:
- Southern United States: late October to early November
- Mid‑Atlantic and Midwest: mid‑October to early November
- Northeastern United States and southern Canada: early to mid‑November
In the Southern Hemisphere, the closing phase occurs in late February to early March.
Factors influencing the exact timing include:
- Microclimate variations (urban heat islands, coastal moderation)
- Elevation (higher altitudes delay onset and accelerate termination)
- Host availability (peak deer, rodent, and bird activity can extend tick presence)
Preventive measures should be implemented from the first expected emergence through the final decline. Regular checks of clothing and skin, use of repellents containing DEET or permethrin, and landscape management (removing leaf litter, maintaining short grass) are most effective when applied throughout the entire activity window.