Flea and Tick Season 101

A large flea and tick on a green chalkboard

Doesn’t it feel like flea and tick season never ends? That’s because in a sense, it doesn’t. Outbreaks—triggered by factors including temperature and humidity levels—affect most parts of the United States throughout the year. Here’s a quick primer so you’re prepared.


Where Fleas and Ticks Roam
Fleas and ticks cover the United States (every state reports activity from both pests), but some regions are much more populated than others. Both fleas and ticks become more widespread when humidity levels are between 50 and 90 percent, and when the temperature is 70°F or greater.

  • Fleas thrive in warm temperatures and high humidity — parameters that are perfect for both their activity and their reproduction. This is why fleas are found in balmy states like Florida throughout the year. Drier or colder regions such as the Southwest and Midwest experience lower (or even zero) activity during winter months.
  • In areas with deep frost, fleas may go dormant for the winter — but not if they’ve made their way indoors. Some sources even suggest that fleas can become more active in early fall, as with dropping temperatures, they are more determined to find the warmth of a host.
  • While ticks thrive in regions with warmer, more humid weather, they are found in woods, shrubs, brush, and undergrowth in most areas of the country, regardless of the climate. They can even be found in forested areas even during colder months. While they generally aren’t active below 45°F, many survive winter by finding cover or hosts.

Regardless of where you live, take extra precaution if your pet likes to go on hikes with you, or likes to roam in fields or on farms, as the risk of a tick infestation increases.

 

Flea Life Cycle Stages
You may be wondering, “How do fleas survive the winter if they thrive around 70°F?” Whether outdoors underneath the snow, or inside in unheated rooms, flea pupae (which enclose themselves in a cocoon until they emerge as full-grown adults) can survive dormant for many months. Adult fleas, larvae, and eggs can survive temperatures as low as 30°F for extended periods. When temperatures become warmer and vibration stirs their cocoons, adult fleas emerge.

 

Sign up for our Flea & Tick Outbreak Alerts to stay informed about outbreaks in your area:

 

What to Keep in Mind:

  • Fleas and ticks affect most parts of the U.S. throughout the year
  • They are most active in the warmer, moist climates
  • Even adult fleas, larvae, and eggs can survive cold weather — as low as 30°F


Flea and Tick Pest Education