Warty "Zombie Squirrels" Are Showing Up in Backyards Across America

A Disturbing Sight in the Backyard

Something deeply unsettling has been turning up in American backyards — squirrels covered in pus-filled, oozing warts, bald patches, and grotesque tumor-like growths. Social media users on Reddit and X shared images showing squirrels with oozing sores and hairless patches across their heads and limbs. The reaction online was swift and visceral. "What is going on with the squirrels lately?! This is the third one I've seen looking like this, and it's honestly freaking me out," one Facebook user wrote. The creatures have been widely dubbed "zombie squirrels" — and it's easy to see why.

These grey squirrels have been spotted in gardens and backyards across parts of the United States, particularly in Maine, and in some regions of Canada. While reports of afflicted squirrels date back to mid-2023, sightings surged again last summer. The images spread rapidly online, triggering fear and confusion among residents who had never seen anything like it — and prompting wildlife experts to step in with some much-needed context.

What's Actually Going On

Wildlife experts say the condition is caused by squirrel fibromatosis, a viral skin disease linked to the leporipoxvirus. This virus spreads through direct contact among squirrels, often via saliva when they fight, groom, or feed in close proximity. The condition creates wart-like growths that can burst and ooze fluid, giving squirrels their terrifying "zombie" appearance. As horrifying as the visuals are, the disease is not new — it has been around since the 1950s.

The tumors can be external, appearing as bulging warts, or internal, potentially affecting organs. While most squirrels eventually recover, in some cases the disease can become fatal. Fibromatosis can be fatal in some cases, such as if the lesions obstruct the eyes or mouth, but the risk of death is generally low. Cases of squirrel fibromatosis are not common and typically affect only a small number of squirrels — usually fewer than 10 in most incidents. There have been historical accounts of more severe outbreaks, however, such as in the late 1990s, which could affect a hundred squirrels at a time.

Should You Be Worried?

The good news is that the virus does not affect humans, pets, or birds. Shevenell Webb of Maine's Department of Inland Fisheries and Wildlife noted that despite their scary look, residents need not fear the squirrels, as they pose no threat to humans, pets, or birds. Still, experts are firm: do not approach or try to rescue an infected animal. Webb told the New York Post, "I would not recommend trying to capture a squirrel that has the virus. It is naturally occurring and will run its course in time."

The rise in sightings has been partly attributed to backyard bird feeders, which serve as congregation points for squirrels. Experts believe that when these animals gather in large numbers around feeders, the risk of spreading the virus multiplies. If you have a backyard bird or squirrel feeder, either remove it or clean it daily, placing fresh food in it every time. That simple step could meaningfully reduce transmission in your neighborhood.

The Bigger Picture

James Parkhurst, an associate professor of wildlife science at Virginia Tech, told Newsweek: "I suspect that current reports of this ailment have gotten an unrealistic level of attention due to the grotesque appearance of affected animals and the ease with which isolated cases can be blown up to create fear or anxiety via social media." In other words, the internet has a way of turning a localized wildlife phenomenon into a perceived apocalypse.

Wildlife officials stress that these cases are part of natural cycles in animal populations, and in most instances, the affected squirrels will heal without human intervention. The zombie squirrel surge is a reminder of how quickly unsettling wildlife images can spread panic — and how a little scientific context can go a long way. If you spot one of these creatures in your yard, keep your distance, clean your feeders, and let nature do what it has been doing for decades.