Squirrels are what Keith Tarvin, a biologist at Oberlin College and Conservatory in Ohio who led the study, calls “public information exploiters,” meaning they often take cues from other prey animals nearby. They’re not the only ones that do this. Early animal behavior studies have shown that birds, mammals, and even fish and lizards can recognize the alarm signals of other species that share similar geographic locations and predators. Within the bird family, a nuthatch may tune into the high-pitched call of a chick-a-dee, which might also be paying attention to the panicked tweet of a tufted titmice.
From Squirrels Speak Bird by Linda Poon