As weird and concerning as they appear, the virus that causes the dark, wart-like horns or tentacles to grow on cottontail rabbits is relatively common and usually not anything to worry about, CPW

Local residents described the rabbits as having “black quills or black toothpicks” growing out of their faces.

Rabbits in Colorado went viral—and sparked concern—after growing black, tentacle-like horns on their head and neck. Thankfully, there’s an explanation that doesn’t involve monster bunnies.