Jackalopes Are Real: Colorado Rabbits Grow Horns Because of a Common Virus
FORT COLLINS, Colorado – August 14, 2025:People near Fort Collins, Colorado, have seen something weird: rabbits with strange, horn-like things growing on their heads and faces. Some say they look like tentacles or black quills. Wildlife experts say it’s not a myth but a real virus. It looks gross, but Colorado Parks and Wildlife (CPW) says it’s not usually deadly to the rabbits and doesn’t hurt people or pets.
What Causes the Horns?
The horns come from the Shope papillomavirus (SPV), also called cottontail rabbit papillomavirus (CRPV). This virus makes wart-like bumps, or papillomas, grow on the rabbits’ skin, usually on their heads. These bumps can get long and hard, looking like horns or tentacles. Dr. Richard E. Shope found the virus in the 1930s. Scientists have studied it a lot, and some think it inspired the jackalope legend.
Rabbits spread the virus through bites from bugs like fleas and ticks, which are around more in the summer. The growths can hang around for years. They usually don’t hurt the rabbit’s insides, but they can cause problems.
How It Hurts the Rabbits
Most wild rabbits can survive the virus, even though the horned rabbits, or Frankenstein bunnies, look scary. Their bodies usually fight off the virus, making the growths get smaller and fall off.
But sometimes, it can be serious. If the growths grow around the rabbit’s eyes, it can’t see well and is easier for predators to catch. If they grow around the mouth, it can’t eat and might starve. Rarely, the bumps can turn into cancer.
It’s Safe for People and Other Animals.
CPW officials say the Shope papillomavirus only affects rabbits. It can’t spread to people, dogs, cats, or other animals. So, there’s no need to worry if you see one.
Even so, they ask people not to touch, feed, or try to help the rabbits. It can stress them out and might spread the virus to other rabbits. CPW says to give them space and watch from far away.
More Rabbit Problems
The papillomavirus isn’t a big problem for the rabbit population, but it’s one of several illnesses affecting them in Colorado. CPW also watches out for Rabbit Hemorrhagic Disease Virus Serotype 2 (RHDV2), which is very contagious and kills rabbits quickly. Unlike the papillomavirus, RHDV2 is a big worry for both wild and pet rabbits and has been a concern in the area since 2020.
These viruses show how wildlife health is delicate. The papillomavirus and how it looks has made people aware of wildlife diseases. Officials are using this chance to teach people why it’s important to stay away from wild animals.
