It's Deer Tick Season—Here's How to Protect Your Dog From Their Bites

dog with mom and kids hiking in the woods
dog with mom and kids hiking in the woods

Pamela Joe McFarlane / Getty

If you live in the Northeastern part of the U.S., finding deer ticks on dogs is probably a regular occurrence.

But these disease-spreading creepy crawlies don't just hang out in New England. Deer ticks, also known as black-legged ticks or by their formal name, Ixodes scapularis, can be found through the eastern half of the U.S., into the Midwest, and up into Canada. While woodland and thick brush are their favorite environments, tall grass and sandy areas suit deer ticks just fine too. They are also hardy, and can be active even in the winter when temperatures are above freezing.

Deer ticks are most famous for carrying Lyme disease and spreading it to both humans and our pets. So keeping deer ticks off your dog is of utmost importance.

What Does a Deer Tick Look Like on a Dog?

Deer ticks are small and dark. If you look closely, the adults have a reddish-brown body with black legs. Adults are only two to three millimeters long, and the nymph and larval stages can be as small as a pinhead.

Deer Tick on leaf
Deer Tick on leaf

KPixMining / Adobe Stock

Deer ticks are the smallest tick in North America, and also one of the plainest. The American dog tick and Lone Star tick both have white ornamentation on their bodies. The brown dog tick and Asian longhorned tick are both solid reddish-brown and larger than deer ticks. While those other types of ticks don't transmit Lyme disease, they can carry nasty surprises of their own, such as ehrlichiosis, Rocky Mountain spotted fever, or anaplasmosis.

When a deer tick hitches a ride on your dog, it will walk along the skin or coat until it chooses a spot to bite. They are usually found on the dog's underside, chest, or face and ears. When it first hops on, you may see the tick walking on your dog's body—it will look like a dark spot that is moving. If your dog has already been treated with a tick preventive medication, the tick may be up on the top of her coat.

After the tick chooses a spot and bites, it will become engorged with blood over the next day or two. An engorged deer tick on your dog will be much larger, expanding up to the size of a corn kernel. (Ew, so gross!) Engorged ticks are also discolored, looking more gray in color the larger they get. Eventually, the tick will finish feeding and fall off your dog.

Because of their small size, you often will not see a tick on your dog (especially if she has a long or thick coat). Many owners first notice a tick as they're petting their dog and feel a new little lump on their skin.

Lyme Disease: The Dangers of Deer Ticks on Dogs

Deer ticks can carry Borrelia burgdorferi, a type of spirochete bacteria that causes Lyme disease. When an infected tick bites your dog, the bacteria enter your dog's bloodstream and travel throughout her body. Favorite hangout spots are the joints and kidneys.

Many dogs who are exposed to the Lyme-causing bacteria do not develop symptoms. But for the unlucky ones, signs of Lyme disease include:

  • Shifting lameness

  • General soreness

  • Swollen joints

  • Poor appetite

  • Fever

In rare cases, Lyme disease can develop into Lyme nephritis, which causes kidney failure. Labrador retrievers seem to be at an increased risk of Lyme nephritis. Symptoms look very similar to kidney failure, and include vomiting and weight loss.

Most veterinary hospitals have in-house blood tests to check for antibodies to the Lyme bacteria. It will take at least four weeks after the initial bite to get a positive test result. Also keep in mind that just because a dog tests positive for antibodies to Lyme, does not mean that she will get sick and show symptoms.

The treatment of choice for most Lyme infections is the antibiotic doxycycline. Dogs who were lame or sore improve rapidly once treatment is started, but it is important to finish the entire course of antibiotics to make sure that all of the invading bacteria have been killed.

You can protect your dog from Lyme disease by keeping her on a tick preventive, checking her for ticks after walks, and vaccinating her against Lyme disease.

Signs Your Dog Was Bit by a Deer Tick

In humans, tick bites tend to develop a characteristic bullseye rash. While this can happen in dogs, it is much less common. Unless you see the tick attached, most deer tick bites on dogs look the same as any other bug bite.

Deer tick bite symptoms can include a small red spot, mild swelling, and itchiness. And if the tick was carrying Lyme bacteria, you'll see those Lyme disease symptoms that are listed above. But the best way to know for sure that a bite was from a deer tick is if you catch the tick in the act—as they're attached to your dog, sucking nutrients from their blood. Otherwise, it can be hard to determine if the bite or spot on their skin was actually a deer tick.

How Check For and Remove Deer Ticks on Dogs

One of the best ways to protect your dog from Lyme disease is to keep ticks off her! Removing any ticks promptly can prevent them from transmitting the Lyme bacteria to your dog.

After walking in the woods or in an area with tall grass, check your dog's entire body thoroughly, including inside her ears and armpits and on her belly. A flea comb is an excellent way to capture invaders (especially for dogs with a thick coat or long hair). Pet parents of short-haired dogs have it a little easier: a lint roller can pick up ticks as long as they're not already burrowed into their coat.

If you have a blow-dryer for your dog, this can make finding ticks really easy on a long-haired dog. You might want to do it outside though so you don't risk blowing ticks around your house.

Once you find a tick, remove it. Ticks that are walking freely can be picked up with a tissue. Ticks that are attached will need to be removed carefully to be sure that you get the entire tick and don't leave its mouthparts behind in your pup's skin. Use tweezers or a tick removal tool, and grasp the tick gently but firmly as close to your dog's skin as possible before slowly pulling back.

Preventing Ticks on Dogs

The best medicine is prevention. To keep deer ticks off your dog, start by avoiding prime tick habitats, such as woods and fields with tall grasses. Ticks are most active in the spring and fall, so it is especially important to keep your dogs out of the brush during these times of year and keep your lawn mowed short to deter ticks from moving in.

There are also a wide range of tick preventive medications on the market. Consult with your veterinarian about the best product for your dog, as all of these medications can have side effects and ticks in some regions may be resistant to certain products.

Spring through fall are the most important time of year to use tick prevention, but remember that ticks can shelter in leaf piles and become active during thaws even in the winter. Many vets will recommend keeping your pooch on their preventative tick medication all year long—even when it's not prime tick season. But even a good old-fashioned "tick check" is a great way to keep your pet safe from these pesky parasites: always check your dog's entire body thoroughly whenever you take her for a walk somewhere that ticks are common, so you can get them off of her before they cause a problem.