When you think of squirrels, you probably imagine cute, fluffy-tailed rodents stuffing their faces with nuts. But this past summer, researchers photographed ground squirrels in California ferociously digging up rodent flesh.

Researchers from the University of Wisconsin-Eau Claire (UW-Eau Claire) and the University of California (UC), Davis, have recorded ground squirrels in California hunting, killing, and eating small rodents called and vole—the first documented evidence of a persistent animal. eating meat. Their findings, detailed in a December 18 study on Journal of Ethologyremind us that our understanding of even the most commonly observed animals is still incomplete.

“We have never seen this behavior before. Squirrels are among the most familiar animals to humans,” said Jennifer E. Smith of UW-Eau Claire in a UC Davis statement. “We saw them right outside our windows; we always hang out with them. But here is this unprecedented-in-science behavior that sheds light on the fact that there is still much to learn about the natural history of the world around us.

Smith leads the Long-term Behavioral Ecology of California Ground Squirrels Project with UC Davis’ Sonja Wild, who also contributed to the study. Last summer, in the 12th year of the project, researchers observed ground squirrels actively hunting voles in 42% of their interactions with small rodents.

“I could hardly believe my eyes,” said Wild. “Since then, we have seen that behavior almost every day. When we started looking, we saw it everywhere.”

The team, including undergraduate students, documented California ground squirrels hunting, eating, and competing against voles in Briones Regional Park in Contra Costa County in June and July of 2024. Carnivorous behavior increased in the first two weeks in July, which coincided with a sudden increase in the vole population.

In fact, squirrels may have started hunting voles with on the rise, according to the study. Scientists once maintained that California ground squirrels were granivorous (eating grain), but now researchers suggest they may be opportunistic omnivores.

“The fact that California ground squirrels can change behavior and respond to changes in food availability may help them survive in environments (that are) rapidly changing due to the presence of humans, ” explained Wild.

“Through this collaboration and the data coming in, we’re able to document this widespread behavior that we didn’t even know was happening,” Smith added. “Digital technology can inform science, but there is no substitute for going out there and witnessing behavior because what animals do always surprises us.”

While the team still has many questions—including how widespread the behavior is, how or if it is passed down to new generations, and how it affects ecological processes—the study increases understanding of scientists of one of the most known animals living nearby. of people.