California Reported to Have Quasi-Cannibal Ground Squirrels – Watts Up With That?

State’s squirrels spotted hunting and decapitating voles (another member of the rodent family). The study’s leader cited human-caused “climate change” while praising this adaptive dietary flexibility.

From Legal Insurrection

Posted by Leslie Eastman

Recent biological research has revealed a shocking shift in the dietary habits of California ground squirrels.

Ground squirrels, which traditionally eat fruits and nuts, have now been observed actively hunting and consuming voles, another member of the rodent family. It is a behavior previously undocumented for this species.

This discovery was part of a long-term study conducted at Briones Regional Park in Contra Costa County, California, as part of the Long-Term Behavioral Ecology of California Ground Squirrels Project.

On one occasion, scientists watched in horror as a squirrel ‘vigorously’ shook its prey while holding it in its mouth.

The observations have suggested that these nut foraging creatures are evolving into carnivorous predators.

‘This was shocking,’ said Dr Jennifer E. Smith, an associate professor of biology at University of Wisconsin-Eau Claire, who led the study.

‘We had never seen this behavior before. Squirrels are one of the most familiar animals to people.’

Researchers have documented killer carnivorous squirrels in California hunting and eating voles:

(Warning: graphic) pic.twitter.com/RbdfHaUHyW

— Steve McGuire (@sfmcguire79) December 19, 2024

According to the LA Times, the mad killing skills of the squirrels impressed the research team.

A video released by researchers shows a ground squirrel grabbing a vole by the neck and shaking it — clear predatory behavior meant to quickly kill prey, said Dan Blumstein, a professor of ecology and evolutionary biology at UCLA who studies marmots, a related species of large ground squirrel. In squirrels, most biological dietary factors, such as their teeth and stomachs, are adapted for vegetation such as nuts and seeds, not meat, he said.

Blumstein, before reading the details of the study, thought that the carnivorous behavior might have been isolated to female squirrels desperate for the nutrients needed to feed their young. But according to the study, the behavior was found in male and female squirrels across age groups. They displayed other behavior typically associated with predators: When one squirrel would successfully hunt down prey, another squirrel would sometimes try to steal it.

“I could barely believe my eyes,” Sonja Wild, a postdoctoral research fellow at UC Davis who co-led the project alongside Smith, said in a release. “From then, we saw that behavior almost every day. Once we started looking, we saw it everywhere.”

Of course, the UC Davis study “expert” quickly linked this behavior to environmental change caused by…humans.

Through videos, photos and direct observations at the regional park, the authors documented California ground squirrels of all ages and genders hunting, eating and competing over vole prey between June 10 and July 30.

The squirrels’ carnivorous summer behavior peaked during the first two weeks of July, coinciding with an explosion in vole numbers at the park reported by citizen scientists on iNaturalist. This suggests that the squirrels’ hunting behavior emerged alongside a temporary increase in the availability of prey, the study said. The scientists didn’t observe the squirrels hunting other mammals.

“The fact that California ground squirrels are behaviorally flexible and can respond to changes in food availability might help them persist in environments rapidly changing due to the presence of humans,” Wild said.

The study leader cited human-caused “climate change” while praising this adaptive dietary flexibility.

“In the face of human insults such as climate change and drought, these animals are resilient and have the potential to adapt to live in a changing world,” Smith adds.

If acorn or seeds fall into low supply, for instance, squirrels appear primed to find other sources of protein and nutrients. The less stubborn an animal is about its diet, the better suited it is for survival. Although in this case, the squirrels don’t seem to be motivated by a scarcity of any other food source, per SFGATE, rather, the high population of voles appears to be the reason for their hunting.

Frankly, there is only one conclusion I can draw from the data presented:

Avoid California, where even our squirrels are vicious killers. Our animal welfare agents wouldn’t dare to take them on. pic.twitter.com/AnVbgXhrdC

— Leslie Eastman ☥ (@Mutnodjmet) December 21, 2024