In addition to seeds and nuts, California ground squirrels also eat voles:
“This was shocking,” said Jenn Smith, an ecologist at the University of Wisconsin-Eau Claire. “We had never seen this behavior before.”
For the study, scientists observed squirrels in a regional park near the San Francisco Bay and consistently saw the creatures hunting down voles. Such sightings, recorded in videos and photographs, coincided with a surge in vole numbers at the height of summer. The research, published in the Journal of Ethology, is the first to find a significant number of squirrels eating meat.
“I could barely believe my eyes,” said coauthor Sonja Wild, a postdoctoral researcher at UC Davis. “From then, we saw that behavior almost every day. Once we started looking, we saw it everywhere.”
Is this news to wildlife professionals? I have seen cute little fawns eat voles made, like so many of us, of tasty meat. And squirrels are aggressive.
On the Faroe Islands, sheep eat the wings off sea gulls.
Bruce asks, “Is this news to wildlife professionals?”
Not really. For a remote example, check that African ground squirrel. The species of which relatively little is known including lifespan, yet on the record as ready to devour anything from fruits to birds.
https://animaldiversity.org/accounts/Atlantoxerus_getulus/#food_habits