A squirrel running with a vole in its mouth in Briones Regional Park, California. (Image credit: Sonja Wild, UC Davis)

Ground squirrels usually eat seeds and nuts, but in a park in California, these cute, furry creatures have turned into carnivorous killers, mercilessly hunting down voles to peel the flesh from their bones.

The squirrel family is known to be fairly flexible when it comes to their dinner. California ground squirrels (Otospermophilus beecheyi) are mostly vegetarian, but they will also eat insects, eggs, hatchling birds and even each other's young, according to the study. However, actively hunting adult mammals still marks a significant shift in the squirrels' behavior.