California Ground Squirrels Have Gone Carnivore, Documented Eating Other Mammals in New Study

Whether or not California ground squirrels have been watching a few of the top influencers on the ‘Gram or are simply gearing up for RFK Jr. to head up the Department of Health and Human Services remains unclear. But what we do know is that they’ve gone full-blown carnivore with their new diet.

According to a study (complete with video evidence) in the Journal of Ethology, these bushy-tailed predators have since been observed hunting, killing and eating other animals including mammals such as California voles for the first time ever.

Traditionally omnivores by nature, squirrel species have been known to dine on insects, frogs and bird eggs in addition to their traditional fare of nuts, seeds and other grains. But this is the first time in history that we’ve ever seen them actively pursue another mammal in search of their next meal.

According to the study’s observations, primarily located at Briones Regional Park in Northern California, out of all the recorded interactions, 42 percent of them resulted in active hunting practices by the subject squirrels.

“Our findings of vole hunting build on reports of infanticide in California ground squirrels, the killing of newly emerged young animals, and isolated events of killing of small prey such as lizards in captivity,” study co-author and University of California, Davis biologist Sonja Wild said. “It is therefore plausible that hunting is innate in these squirrels to an extent. Yet, in our twelve years of conducting observations on hundreds of squirrels we had never observed any incidents of vole hunting before this summer.”

“This was shocking,” study co-author and University of Wisconsin-Eau Claire biologist Jennifer E. Smith said in a statement. “We had never seen this behavior before. Squirrels are one of the most familiar animals to people. We see them right outside our windows; we interact with them regularly. Yet here’s this never-before-encountered-in-science behavior that sheds light on the fact that there’s so much more to learn about the natural history of the world around us.”

Researchers relied on a combination of photos, videos and direct observations to record the peculiar interactions between the squirrels and their prey, noting that their hunting behavior peaked during early July. The study also noted that this increase in hunting coincided with a larger instance of voles in the park and hence, available prey. 

While many predatory animals are opportunistic in nature, researchers remain baffled as to why exactly it is that these squirrels turned to the vole populations for food. 

“Through this collaboration and the data coming in, we’re able to document this widespread behavior that we had no idea was going on,” said Smith. “Digital technology can inform the science, but there’s no replacement for going out there and witnessing the behavior because what animals are doing always surprises us.”

In a world where everyone seems to be being pulled into a more natural way of eating (read: eating meat), perhaps the human influence is being passed down to our furry friends looking for a bump in longevity. But until researchers get back out in the field to observe these critters again next summer, the questions surrounding the impact of squirrels packing on protein and the effects it might have on their reproduction rates will remain unanswered - at least for now.