Are There Ticks in Colorado? A Guide to Colorado Tick Species

Ticks are one of the most common parasites in North America, and they're not too picky about where they get their next meal. These bloodsucking arachnids are known to feed on everything from reptiles and amphibians to birds and mammals, including dogs, deer, and horses.

Unfortunately, humans are on the menu for these pesky parasites, too. If you spend a lot of time outside, chances are that you've probably had to pick a couple of ticks off you or your dog before.

But whether you've had any close encounters with these ectoparasites or not, it's important to know about the tick species in your area to better protect you and your family from species that are known to carry diseases. Here is everything you need to know about the tick species that call the Centennial State home.

Does Colorado Have Ticks?

Like most locations in North America, you can find many species of ticks throughout Colorado. This is not surprising, considering ticks belong to one of the largest sub-orders of arachnids, Ixodida.

There are over 800 species of ticks worldwide and nearly 100 in the United States alone. Luckily, only a small percentage of tick species call Colorado home. And only a small subset of those pose any danger to humans.

How Common Are Ticks in Colorado?

Ticks are very common in Colorado. They are found throughout the entire state, hanging on leaves, grass, and other vegetation, waiting for an unsuspecting host to brush up against them. However, their population density can vary substantially from one location to another.

Wooded areas, fields, gardens, shrubland, and other grassy areas have the largest concentration of ticks. You may even find some in your own yard. Ticks are very hardy and can survive in both urban and rural environments, which is why it's important to always stay vigilant when spending time outdoors.

Types of Ticks in Colorado

Whether you're an avid outdoorsman or a concerned dog owner, understanding Colorado's tick population and the different types of ticks can help you stay safe.

There are approximately 30 unique species of ticks in Colorado. But you really only need to be on the lookout for a handful of the most common types known to carry serious disease germs.

Here are the common tick species encountered in Colorado, with tips on how to identify them, and what risks they carry.

**The Rocky Mountain Wood Tick (Dermacentor andersoni)**

The Rocky Mountain Wood Tick in Colorado

As its name suggests, the Rocky Mountain wood tick is commonly found in wooded areas and shrublands throughout Colorado. They are generally subalpine. But they have been found in alpine locations as well.

It's usually tough to distinguish these ticks from another species, the American dog tick due to their similar appearance. The key identifying feature between the two types requires a microscope and a trained eye. Rocky Mountain wood ticks are generally more common in most areas especially at higher elevations. Both types are most commonly encountered in their adult stage from June to August.

These ticks are especially hardy and can survive for up to two years without a single meal. But when they finally get a bite, they may potentially transmit Colorado tick fever virus or Rocky Mountain spotted fever. Colorado tick fever virus is only transmitted to humans, whereas cats and dogs are also susceptible to Rocky Mountain spotted fever.

When a female Rocky Mountain wood tick finds a host, she may feed for anywhere from 4 to 17 days before she detaches and lays up to 6,000 eggs. It's rare to encounter eggs, larvae or nymphs, but these wood ticks can transmit disease germs during every active life stage.

**The American Dog Tick (Dermacentor variabilis)**

The American dog tick is a common tick species found in grassy areas throughout Colorado and the rest of the country. In addition to grassy areas, these ticks like to hang out around the edge of wooded areas. This means they're a common sight on nature trails and walkways.

Larvae and nymphs tend to feast on small mammals, such as mice, squirrels, and voles. On the other hand, adults tend to go for mid-size mammals, such as cats, dogs, and raccoons. However, these larger ticks are also known to parasitize humans.

When American dog ticks latch onto humans, it's most commonly near the crown of the head. Males will usually attach and feed for short periods before detaching themselves and go in search of a female to mate with. Females may feed for up to a week or longer before becoming fully engorged. Amazingly, these ticks can live for up to two years during any life stage without a host.

Nymphs and adults of this species may transmit Rocky Mountain spotted fever and other bacterial and viral infections, but they are not known to transmit Lyme disease.

**The Brown Dog Tick (Rhipicephalus sanguineus)**

Brown dog ticks are found around the world, but not where you may think. Unlike most ticks that dwell in wooded or grassy areas, brown dog ticks thrive in human settlements and can spend their entire life indoors. They tend to select domestic dogs as hosts but may feed on human blood as well.

These ticks are known for transmitting canine diseases, including Rocky Mountain spotted fever and canine babesiosis, but they rarely transmit diseases to humans. In the Four Corners region, transmission of RMSF by this tick is more common and poses a significant public health threat. It's important to check your furry friends regularly, as brown dog ticks can easily infest homes.

**The Lone Star Tick (Amblyomma americanum)**

Lone Star ticks are not all that common in Colorodo and are mostly encountered in the Eastern Plains region. They are aggressive ticks, even seeming to seek out humans as hosts. They are mostly found in woodlands with dense undergrowth and both nymph and adult stages are most active between April and August.

Female Lone Star ticks are easy to identify, thanks to the single white dot they bear in the middle of their brown bodies. On the other hand, males tend to have white spots or streaks around their edges. However, these markings are not always easy to see without a closer look, so it's easy to confuse them with other species. Nymph lone stars don’t have any white pigment on their body.

Interestingly, this tick's bite has a rare potential side effect. Injection of this tick's saliva when it bites may result in the host developing alpha-gal syndrome — an allergy to red meat. More specifically, this allergy is to galactose-alpha-1,3-galactose, a type of sugar molecule present in meat and other products from many mammals, but not in reptiles or birds.

Additionally, these ticks do not transmit Lyme disease, but they can transmit other diseases, including human monocytic ehrlichiosis, southern tick-associated rash illness (STARI) borreliosis, and more rarely Rocky Mountain spotted fever.

When Is Tick Season in Colorado?

The tick population ebbs and flows throughout the year. However, ticks in Colorado are most active in spring and early summer. Tick season usually starts in March and reaches its peak in May and June, making this the worst time for ticks in Colorado.

Their numbers and activity tend to die back by the end of summer or early fall. It's rare to see a tick after September.

Staying Safe Doesn't Have to Be Difficult

Ticks are incredibly common in nature and are known to parasitize humans and transmit several serious bacterial and viral infections. That’s why it's important to take appropriate precautions when spending time outside.

Luckily, this is easy to do by simply wearing the proper clothing. Insect Shield offers Permethrin treated clothing and other gear to protect against ticks for every member of the family. Explore the Insect Shield shop today to find comfortable and protective clothes for your next outing or everyday use.