American Dog Tick: Essential Facts for Pet Owners

The American Dog Tick is a common parasite that can cause significant health problems for both humans and animals.

These ticks are found across the United States and are known to carry a variety of pathogens that can lead to serious illnesses, such as Rocky Mountain spotted fever.

Learning about this tick species is essential for ensuring the safety and well-being of our pets and ourselves.

Ticks are small arachnids that feed on the blood of animals, including humans. The American Dog Tick is known scientifically as Dermacentor variabilis and thrives in grassy, wooded areas.

It is essential for people to be aware of the presence of these ticks, how to identify them, and how to prevent tick bites.

In warmer months, American Dog Ticks are most active, putting outdoor enthusiasts and their pets at risk.

It is important to take proactive measures, such as using tick repellents and checking yourself and your pets for ticks regularly, to minimize the risk of tickborne illnesses.

American Dog Tick Basics

The American dog tick is an arachnid responsible for transmitting diseases such as Rocky Mountain spotted fever and tularemia. Adult ticks have eight legs and can vary in size depending on whether they have fed or not.

Life Cycle

The life cycle of the American dog tick consists of four stages:

  • Egg
  • Larva
  • Nymph
  • Adult

Ticks need a blood meal to grow to the next stage. They also need at least three different hosts to complete these stages (larva, nymph, and adult) of their life cycle. The entire life cycle spans from one to two years.

Habitat and Distribution

American dog ticks thrive in:

  • Grassy areas
  • Along trails
  • Forest edges

These ticks are predominantly found east of the Rocky Mountains, with a few species located west of the Rockies.


Ticks can latch onto a variety of hosts, including:

  • Humans
  • Dogs
  • Rodents
  • Cats
  • Skunks
  • Various large mammals

Tick-Borne Diseases

Rocky Mountain Spotted Fever

Rocky Mountain Spotted Fever (RMSF) is a severe illness caused by the bacteria Rickettsia Rickettsii. It is transmitted through the bite of infected American Dog Ticks. Symptoms include high fever, headache, muscle aches, and a distinct rash.

Lyme Disease

Lyme Disease is caused by the bacteria Borrelia burgdorferi, transmitted through the bite of infected black-legged ticks. It is known for its classic “bulls-eye” rash, along with fever, fatigue, and muscle aches.


Babesiosis is caused by microscopic parasites infecting red blood cells. It is transmitted by black-legged ticks and causes flu-like symptoms, including fever, fatigue, and anemia.


Ehrlichiosis is caused by bacteria from the Ehrlichia family. Ticks transmit this disease to humans, with symptoms including fever, headache, muscle pain, and a rash in some cases.


Tularemia is caused by the bacteria Francisella tularensis. It can be transmitted through the American Dog Tick’s bites and manifests with fever, swollen lymph nodes, and skin ulcers.


Anaplasmosis is caused by the bacteria Anaplasma phagocytophilum, transmitted through the bite of infected black-legged ticks.

Symptoms include fever, headache, muscle pain, and possible gastrointestinal issues.

Alpha-Gal Syndrome

Alpha-Gal Syndrome is a tick-induced allergy to red meat, associated with bites from the Lone Star Tick. It can cause symptoms such as itching, hives, or severe allergic reactions.

Disease Causative Agent Symptoms Tick Species
Rocky Mountain Fever Rickettsia rickettsii Fever, rash, headache, muscle pain American Dog Tick
Lyme Disease Borrelia burgdorferi Bulls-eye rash, fever, fatigue, muscle aches Black-legged Tick
Babesiosis Babesia microti Fever, fatigue, anemia Black-legged Tick
Ehrlichiosis Ehrlichia chaffeensis Fever, headache, muscle pain, rash (sometimes) Lone Star Tick
Tularemia Francisella tularensis Fever, swollen lymph nodes, skin ulcers American Dog Tick
Anaplasmosis Anaplasma phagocytophilum Fever, headache, muscle pain, gastrointestinal issues Black-legged Tick
Alpha-Gal Syndrome Galactose-α-1,3-galactose Itching, hives, severe allergic reactions Lone Star Tick

Symptoms and Detection

Symptoms in Dogs

  • Fever: Dogs infected with the American Dog Tick may experience fever, causing them to be lethargic and unresponsive.
  • Skin irritation: Infected ticks can cause redness, swelling, and itchiness on the dog’s skin where the tick has bitten.

Symptoms in Humans

  • Fever: Just like dogs, humans can also experience fever when bitten by an infected American Dog Tick.
  • Rash: Rashes may appear around the tick bite area, typically with a red, raised appearance.

Infected Tick Bite

An infected tick bite may have the following characteristics:

  • Redness and swelling around the bite area
  • Pain or burning sensation
  • Formation of a rash or blisters


A rash caused by the American Dog Tick can exhibit:

  • Red, raised patches on the skin
  • Itchiness and irritation
  • Possible blistering or flaking

Prevention and Control

Protecting Your Pets

  • Daily checks: Examine your pets every day, particularly after spending time outdoors. Focus on areas like in and around the ears, around the eyelids, under the collar, and under the front legs 1.
  • Tick prevention products: Use veterinarian-recommended tick prevention products on your pets to keep them safe from ticks and tick-borne diseases 2.

Protecting Your Yard

  • Landscape maintenance: Keep grass short, clear brush, and get rid of leaf litter in your yard to minimize tick habitats 3.
  • Restricting wildlife: Use fencing to keep out large animals like deer that can bring ticks into your yard 4.

Personal Protection

  • Repellents: Apply EPA-registered insect repellents to your skin and clothing to deter ticks 5.
  • Avoiding tick habitats: Stay away from grassy, brushy, or wooded areas where ticks are likely to live 6.

Comparison between Tick-Prevention Measures:

Method Pros Cons
Daily checks Simple and low-cost Time-consuming
Tick products Effective in preventing tick infestations May contain chemicals
Yard maintenance Long-term solution to reduce tick habitats Labor-intensive
Protective clothing Reduces risk of tick bites Limited effectiveness

Remember to always consult your veterinarian for the best methods of tick prevention for your pets.

Dog Tick

Also, stay vigilant in maintaining your yard and personal protection measures to minimize the risk of tick-borne diseases.

Tick Removal and Treatment

Safe Tick Removal

To safely remove an American dog tick, use clean, fine-tipped tweezers to grasp the tick as close to the skin’s surface as possible.

Pull upward with steady, even pressure to avoid twisting or jerking which might cause parts of the tick to break off and remain in the skin. Keep these steps in mind:

  • Use fine-tipped tweezers.
  • Grasp tick close to skin.
  • Pull upward with steady, even pressure.

When to See a Doctor

If you are bitten by a deer tick, it’s important to monitor yourself for any symptoms of tick-borne diseases, such as fever, fatigue, muscle aches, or rash.

In such cases, see a doctor as soon as possible. If you notice:

  • Fever or rash
  • Fatigue or muscle aches
  • Signs of infection at the bite site

Blood Test

A blood test may be necessary to detect any tick-borne diseases, such as Lyme disease or Rocky Mountain spotted fever.

Blood tests can check for the presence of antibodies or bacteria related to these diseases. Your doctor may recommend a blood test if you:

  • Show symptoms of tick-borne illness.
  • Recently had a tick bite.

Other Tick Species

Lone Star Tick

The Lone Star tick is found primarily in the south-eastern parts of the United States. Its bite may cause a red meat allergy. The female tick has a single white-colored spot on the back.

  • Known to transmit diseases like Ehrlichiosis and STARI
  • Found in wooded areas and tall grass

Black-Legged Tick

Also known as the Deer tick, the Black-legged tick is common in the eastern US. It can transmit Lyme disease.

  • Usually found in wooded and grassy areas
  • Active year-round, but mostly during the spring and summer months

Gulf Coast Tick

Gulf Coast ticks are primarily found in the southeastern US and parts of Mexico. They transmit diseases like Rickettsia parkeri rickettsiosis.

  • Found in grassy or sandy areas, particularly along the coast
  • Affects both animals and humans

Rocky Mountain Wood Tick

The Rocky Mountain Wood tick is found in the western US and Canada. It can transmit Colorado tick fever, Rocky Mountain spotted fever, and tularemia.

  • Common in higher elevations (4,000 to 10,000 ft)
  • Active during the spring and early summer months

Brown Dog Tick

Brown Dog ticks are found across the United States. These ticks primarily infest dogs and can transmit canine diseases, human ehrlichiosis

  • Can survive indoors and outdoors
  • Females can lay up to 5,000 eggs at once

Hard Ticks and Soft Ticks

There are two main categories of ticks: hard ticks and soft ticks.

Hard ticks:

  • Possess a hard plate (scutum) on their back
  • More common and known for transmitting diseases

Soft ticks:

  • Do not have a scutum
  • Rounded in appearance
  • Can transmit tick-borne relapsing fever
  Hard Ticks Soft Ticks
Appearance Hard plate (scutum) No scutum
Shape Flat and oval Rounded
Diseases Commonly transmit Less likely to transmit

Dog Tick

Centers for Disease Control Recommendations

The Centers for Disease Control (CDC) recommends taking the following preventive measures against American dog ticks:

  • Avoid tick habitats: Avoid areas with high grass, brush, or wooded areas where ticks are commonly found.
  • Use tick repellent: Apply repellents containing at least 20% DEET on exposed skin and clothing to reduce the risk of tick bites.
  • Wear protective clothing: Opt for long-sleeved shirts, long pants, and closed-toed shoes when outdoors in tick-infested areas.

Tick population is higher in the Northeast region of the United States, making preventive measures even more critical in those areas.

Measure CDC Recommendation
Clothing Long sleeves, long pants, closed-toed shoes
Repellent 20% DEET or higher
Habitat Avoid high grass, brush, wooded areas

By following these recommended precautions, you can significantly reduce your risk of encountering the American dog ticks and protect yourself from potential tickborne diseases.


The American Dog Tick, a common parasite found throughout the US, carries dangerous pathogens causing illnesses like Rocky Mountain spotted fever.

Awareness and preventive measures, such as using tick repellents and regular checks, are essential for protecting humans and pets from tickborne diseases. Stay vigilant and follow CDC recommendations to minimize the risk of encounters and promote a safer environment.




  1. How to Check Your Pet for Ticks | Healthy Pets, Healthy People | CDC
  2. Preventing ticks on your pets | Ticks | CDC
  3. Preventing tick bites | Ticks | CDC
  4. American dog tick | Ticks | CDC
  5. Preventing tick bites | Ticks | CDC
  6. Preventing tick bites | Ticks | CDC


Readers’ Mail

Over the years, has received hundreds of letters and some interesting images asking us about these ticks. Scroll down to have a look at some of them.

Letter 1 – Dog Tick

Son (partially) ate this blood-containing insect. Help!
December 28, 2009
Photos are of a non-eaten, but same, insect. Flea? Tick? Found indoors in Berkeley, CA home during cold, intermittently rainy weather. Had not noticed any before in 4 years here; recently have seen several. Dog present in home. Have not noticed any bites on people in home.

Possibly an intermittent stage (a pupa?)as the whitish covering seems to conceal a brown, patterned surface. Very slow-moving; 1/4th of an inch long, a little under 1/8th inch high. Bean-shaped body (i.e., not flattened).

Contained enough of what I think was animal or human blood (reddish brown, iron-scented and tasting) to cover my 13 month old’s chin. Worried about tapeworms, Lyme diease, other things I don’t even know about!
What is it??
Worried mom
Berkeley (Northern coastal) CA

Dog Tick
Dog Tick

Dear Worried Mom,
This is a Tick, probably an American Dog Tick, Dermacentor variabilis.  Though dogs are the preferred host, they will bite humans.  Ticks are known vectors for disease, and you should try to rid your dog and home of this blood sucker.

Hello Daniel,
Thank you!  I looked at pictures of ticks on the internet, but all the descriptions seemed to
be of a much smaller insect.  Our local vector control, which offers an insect ID service, is closed for the holidays for budgetary reasons.
I will now look into safe ways of getting rid of ticks.

Hi again Gretchen,
Ticks increase in size when they are engorged with blood like the specimen in the photo you provided.

Letter 2 – Dog Tick

Green Shell Bug
May 27, 2009,
The Green shell bug has very small brown legs and an almost nonexistent face. I found it near our front door by the dog kennel. We are in Northwestern Virginia.

If the bug is on it’s back it can’t make it’s self upright again and it doesn’t appear to have wings. It measured as 1 1/2 cm long, it’s legs are sticky.
What bug is this, my girls ages 8 and 6years would love to know.
Northwestern Virginia

Dog Tick
Dog Tick

Dear Nancy,
First, we apologize for the six week delay.  Our fast new computer is allowing us to answer so much more than before. 

We are going to try to select one letter a day from our oldest archived requests in an attempt to provide a service to our readership.  Now the bad news.  This is a Dog Tick.  It looks to be engorged with blood.  Ticks can carry diseases.

Letter 3 – American Dog Tick

Possible tick found?
I live in Rockford, Illinois (obviously USA) and this area isn’t really known for ticks unless you go into woods. Otherwise no ones sees them. I live in what you could consider a brady bunch sorta neighborhood. Anywho I was in my moms computer room and saw this bug crawling.

I immediately thought it was a tick as my dog has had one before and seen one crawling on me once after a game some friends and I had played in the woods some years ago but I know they don’t die when squashed. I smashed it as hard as I could and threw it in the toilet and was still alive trying to swim around the water.

I’m hoping I’m wrong as i hate ticks but mabye you could tell me more? Thanks for the response if given one. I also uploaded the picture to just in case it doesn’t show up in the email as you stated some pics weren’t showing up.

This is most probably an American Dog Tick, Dermacentor variabilis. BugGuide has images from Illinois

Letter 4 – American Dog Tick

Great web site
thanks for your help on my recent submissions. Your web site is great. I’ve been photographing crawling critters for a few years and it’s nice to have a place to identify these little marvels. I’m sending you a few more that you can use on your site if you’d like.

I photographed the Ladybugs at the Richard Nixon Library in Yorba Linda Ca. The Millipede came from Heber Springs, Arkansas. The Female American Dog Tic, hitch-hiked on me while on a trail in Anaheim Ca.
Thanks again

Hi Rus,
Thanks for the Tick image. BugGuide has a nearly identical photo, but there seems to be some question as to whether it is a Dog Tick.


  • Bugman

    Bugman aka Daniel Marlos has been identifying bugs since 1999. is his passion project and it has helped millions of readers identify the bug that has been bugging them for over two decades. You can reach out to him through our Contact Page.

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  • Piyushi Dhir

    Piyushi is a nature lover, blogger and traveler at heart. She lives in beautiful Canada with her family. Piyushi is an animal lover and loves to write about all creatures.

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3 thoughts on “American Dog Tick: Essential Facts for Pet Owners”

  1. Please some one tell me what this bug is, the picture is included. I keep finding these things near my window, and in the carpet. Most times I find them dead, but I don’t know where they are coming from, or what they are.

    HELP! I hate bugs… I found one on my hand one time, and it freaked me out!

    • There is a different submission form for posting images. Go to Ask What’s That Bug? and do not check comment, but fill in the information and attach the image.


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