The Dangers of the Deer Mouse

As cute as it appears to be, the gray to brown and white deer mouse (Peromyscus maniculatus) is a potentially dangerous creature since it can spread disease.

The deer mouse is about five inches long, with:

• Big eyes
• Ears that are prominent and leaf-like, but generally shorter than a hindfoot
• Head and body of about two to three inches long
• Tail at about the same; another two to three inches long.

This rodent gets its name from the fact that it resembles a deer. Its upper body is gray to reddish-brown, its underbelly and legs are white, and its tail is bicolored—dark on top and white on the sides and bottom. The deer mouse is omnivorous, eating just about anything, and nocturnal, being most active at twilight. Unlike other mice, it is not a very good climber.

Dangers of the Deer Mouse

This cute-looking rodent carries and spreads Lyme disease and is the primary carrier of hantavirus in the U.S.

• Lyme disease: Deer mice also transmit Lyme disease. This disease is carried by a bacteria that is transmitted by the deer tick between mammal hosts, such as deer mice, rabbits, white-tailed deer, and, yes, humans.
• ​Hantavirus: The disease is transmitted primarily through the inhaling of contaminated air, but also through contact with the urine, feces, or saliva of infected mice. Because there is still no recognized cure, it is important to avoid contact with deer mice and areas they are known to frequent or where infestations are or have been present.

The white-footed mouse, rice rat, and cotton rat can also carry hantavirus strains. Because other rodents may present dangers, it is wise to avoid close contact with rodents in general.

Where Do Deer Mice Live?

Deer mice can be found all throughout North America, most often in woodlands, prairies, and bushy areas. If you are located in the United States, chances are that deer mice may live in your neck of the woods, with the exception of some parts of the southern and eastern United States, including Florida.

This mouse will also make its home in urban areas. In fact, it will live about anywhere it finds concealed shelter with food nearby, such as in underground burrows, brush piles, and weedy/grassy areas; under logs, stumps, or rocks; and in abandoned dens of other animals and cavities of trees.

Signs of Infestation

You will likely not see or hear nocturnal deer mice during the day, but at night, you may hear scurrying, particularly in crawl spaces, basements, or even attics. Though mice will be hidden, you may see their droppings or their food stashes, and you may find objects that have been gnawed upon, like boxes.

It's even possible to see a deer mouse nest, but it's important that you stay clear of it, given their association with viruses.

What to Do If You Have Deer Mice

If you have deer mice in your home, you can set traps and use rodent bait to catch them, but be sure to take special care when disposing of any bodies, using gloves and washing your hands. Your best bet is to call a professional, especially if you suspect a serious infestation.

Prevention is key when dealing with deer mice. Seal up any small holes in your home or garage to block the mice from entry, and don't leave out any exposed food that may tempt the mice into your living space.