Squirrels are far noisier than their quiet nut-gathering image suggests. They bark, chatter, squeak, whistle, and click.1Frontiers in Ecology and Evolution. Think Before They Squeak: Vocalizations of the Squirrel Family Most of what people notice is a warning, a squirrel telling others that danger or a rival is nearby.2Ecosphere. Behaviors associated with vocal communication of squirrels Their calls can carry surprisingly specific information, including what kind of threat is around and even which squirrel is calling.
Barks, Kuks and Moans Mean Danger Is Near
An alarm call is a sound a squirrel makes when it senses danger, and it changes how nearby squirrels behave.3Adaptive Behavior. Hidden Markov models of eastern gray squirrel (Sciurus carolinensis) alarm calls Eastern gray squirrels, the common backyard squirrel in much of North America, use three of them: short barking “kuks,” longer raspy “quaas,” and drawn-out “moans.”4Ethology Ecology & Evolution. Gray squirrel alarm call composition differs in response to simulated aerial versus terrestrial predator attacks Lots of kuks and quaas usually mean a ground threat such as a cat, dog, fox, or a person. Moans are given mostly for threats from the air, such as a hawk overhead.5Ethology Ecology & Evolution. Gray squirrel alarm call composition differs in response to simulated aerial versus terrestrial predator attacks How fast and how long the squirrel calls also carries information about the threat.6Adaptive Behavior. Hidden Markov models of eastern gray squirrel (Sciurus carolinensis) alarm calls Red squirrels can keep up alarm bouts of hundreds of calls lasting up to 11 minutes, and sometimes keep calling after the predator has gone.7Animal Behaviour. Predator‐associated vocalizations in North American red squirrels (Tamiasciurus hudsonicus): are alarm calls predator‐specific?
A squirrel giving an alarm freezes on a trunk or branch, facing the threat, and repeats short barks for minutes, often with a quivering tail. Other squirrels stop feeding, look up, or dash for the trees. If you can’t tell what set it off, look where the squirrel is facing, since it usually stares at one spot.
Choppy, repeated barks point to something on the ground, so check there first. Long, low moaning suggests a hawk or owl, so scan the sky and treetops.
It’s easy to assume the squirrel is angry at you personally. The calls are mostly a message to other squirrels, not to the threat itself, and a person walking through a yard can simply be the nearest possible danger. Stepping back, or taking the dog indoors, usually calms the calling within minutes.
What a Flicking Tail Adds to the Noise
Gray squirrels often flick or wave their tails while giving alarm calls.8Behaviour. Joint tail and vocal alarm signals of gray squirrels (Sciurus carolinensis) Together, the tail flags and moans signal more clearly than either alone whether the threat is on the ground or above.9Behaviour. Joint tail and vocal alarm signals of gray squirrels (Sciurus carolinensis) Wild squirrels react to a bark alone or a tail flag alone, but they react most to both together.10Current Zoology. Multimodal alarm behavior in urban and rural gray squirrels studied by means of observation and a mechanical robot
Two signals help in a noisy, leafy yard. Wind, traffic, or a lawn mower can drown out a bark, while leaves and branches can hide a waving tail from a squirrel on the far side of a tree, where the sound can still get through. With both, at least one is likely to reach a neighbor, and the pairing makes the warning harder to ignore, so neighbors react faster.
Not every tail movement is an alarm. Relaxed squirrels use the tail for balance while running or leaping. An alarm flick is sharp and repeated, and it comes with barking. A flick plus a freeze plus calling means the squirrel is on alert.
Rattles, Chatters and Teeth Clicking Toward Other Squirrels
Red squirrels give a loud rattle when another squirrel enters their territory.11Current Zoology. Who’s your neighbor? Acoustic cues to individual identity in red squirrel Tamiasciurus hudsonicus rattle calls Each squirrel’s rattle is distinct enough that its voice can be told apart from its neighbors’.12Current Zoology. Who’s your neighbor? Acoustic cues to individual identity in red squirrel Tamiasciurus hudsonicus rattle calls In one test, calls could be matched to the right squirrel about 55% to 75% of the time among neighbors.13Current Zoology. Who’s Your Neighbor? Acoustic Cues to Individual Identity in Red Squirrel (Tamiasciurus hudsonicus) Rattle Calls Red squirrels guard a single food store year-round, so they advertise ownership loudly and often.
A territorial dispute sounds different from a predator alarm. A rattle is a long, buzzing burst, quite unlike the evenly spaced barks of an alarm. A dispute usually involves two squirrels chasing each other in spirals around a trunk, while an alarm usually involves one squirrel fixed in place and staring at something. Chases produce their own calls. In California ground squirrels, a squirrel chasing a rival gives lower, more wavering calls than one warning of a predator, and the squirrel being chased gives calls in between the two.14Wiley Online Library. Single-note Vocalizations of California Ground Squirrels: Graded Signals and Situation-specificity of Predator and Socially Evoked Calls
A threatened squirrel may also clatter its teeth together in rapid clicking, a defensive warning often heard near a nest or food stash.15Central Florida Trapper. Squirrel Sounds Identification Guide – Central Florida Trapper Clicking at close range means back off rather than danger nearby. Move away calmly and give it room, and avoid reaching toward it, since a threatened squirrel may bite.
Baby Squirrel Cries, Distress Screams and Mating Calls
Squirrel sounds include distress calls, calls from babies, and contact calls used to stay together.16Ecosphere. Behaviors associated with vocal communication of squirrels Across species, babies make ticking and isolation calls when separated.17Zeitschrift für Tierpsychologie. Sound Communication among African Rainforest Squirrels Mother Columbian ground squirrels become alert and approach the sound of a pup’s distress call.18Journal of the Arizona-Nevada Academy of Science. Scream of Death: Responses of Female Columbian Ground Squirrels to Anti-Infanticide Pup Distress Calls They respond based on whether the call comes from their own territory, not by recognizing their own pup’s voice.19Journal of the Arizona-Nevada Academy of Science. Scream of Death: Responses of Female Columbian Ground Squirrels to Anti-Infanticide Pup Distress Calls
If you find a crying baby squirrel, it’s often best to leave it for a while so its mother can find it. Watch from a distance for a couple of hours, keeping people and pets away so she feels safe coming back. A mother will often retrieve a pup that has fallen or wandered. Call a wildlife rehabilitator if the baby is injured, cold, or still alone after that wait. Don’t feed it or give it water, because the wrong food or liquid can harm a young squirrel.
A distress scream sounds different from an alarm. Screams are piercing and erratic, while alarms are rhythmic. A scream often means a squirrel is caught or injured, so check for one trapped in netting or a fence, or caught by a pet.
Mating adds its own noise. Male Columbian ground squirrels give a mating call, always after mating.20Animal Behaviour. Why do male Columbian ground squirrels give a mating call? The callers are usually older males holding a territory and guarding a mate.21Animal Behaviour. Why do male Columbian ground squirrels give a mating call? Breeding seasons, in late winter and summer, bring chases between males that produce rattles and squeals on top of the usual alarms. Noisy spirals around trunks at those times are often courtship.
Sounds Too High for People to Hear
Richardson’s ground squirrels can give alarm calls that are ultrasonic, meaning too high-pitched for people to hear.22PubMed. Animal communication: ground squirrel uses ultrasonic alarms Such calls are very directional and can’t be heard by key predators.23PubMed. Animal communication: ground squirrel uses ultrasonic alarms Their audible alarms sit around 8 kHz while their silent ones sit around 48 kHz, far above the human limit of about 20 kHz.24Canadian Journal of Zoology. The adaptive utility of Richardson’s ground squirrel (Spermophilus richardsonii) short-range ultrasonic alarm signals The farther the threat, the more the squirrels use silent calls, warning neighbors without tipping off the predator.25Canadian Journal of Zoology. The adaptive utility of Richardson’s ground squirrel (Spermophilus richardsonii) short-range ultrasonic alarm signals A loud call tells a hawk exactly where the caller is, while a short-range call warns neighbors close by without carrying far.
If you watch a ground squirrel colony, you may see squirrels suddenly stand up, freeze, or dive into their burrows even though you heard no alarm at all. A call too high-pitched for people to hear may have set it off, and the behavior is often the only sign a warning went out. Bat detectors that convert high sounds into audible ones can reveal calls you would otherwise miss.
Chirps and Squeaks at Night From Flying Squirrels
Northern and southern flying squirrels have rich call sets of chirps, trills, barks, and upsweeps, with 10 types in northern and 27 in southern flying squirrels.26Journal of Mammalogy. Vocal repertoire of captive northern and southern flying squirrels (Glaucomys sabrinus and G. volans) Juvenile southern flying squirrels make trills and tonal chirps.27Journal of Mammalogy. Vocal repertoire of captive northern and southern flying squirrels (Glaucomys sabrinus and G. volans) They call most just after sunset and again before sunrise.28PubMed Central. Seasonal variation in the ultrasonic vocal activity of Humboldt’s flying squirrel (Glaucomys oregonensis) Faint chirping in walls or an attic at dusk and dawn fits flying squirrels better than tree squirrels, which are active by day. Flying squirrels nest in groups and may use high calls to regroup at the nest after feeding.29PubMed Central. Ultrasonic Vocalizations Emitted by Flying Squirrels
Other attic animals sound different. Gray squirrels are mainly active in early morning and late afternoon, while flying squirrels are active at night. Mice make faint scurrying sounds, while flying squirrels are heavier and thump as well as chirp. Rapid scampering around dusk suggests flying squirrels leaving the nest to feed. The time of day is a clue, though not proof, so look outside for confirmation.
If you suspect squirrels in your attic, watch at dusk for animals gliding or climbing from the roofline, which shows where they come and go. Check vents, soffits, and gaps near the roof for openings. Avoid sealing openings in spring, when babies may be inside, because trapped young will die and their mother may damage the house trying to reach them. A licensed wildlife removal service can install one-way exits that let animals leave but not return.
How Squirrels Listen to Birds
Gray squirrels hearing relaxed bird chatter look up less often than squirrels hearing only background noise.30PubMed Central. Eavesdropping grey squirrels infer safety from bird chatter After a hawk call, squirrels hearing bird chatter calm down faster.31PubMed Central. Eavesdropping grey squirrels infer safety from bird chatter California ground squirrels become more alert at the alarm calls of most nearby bird species, but don’t react to their songs.32Biology. Interspecies communication and alarm call eavesdropping on multiple birds by a sympatric mammal
You can see this at a bird feeder. A burst of alarm calls from jays or chickadees can send squirrels up a tree or into cover, while steady, relaxed birdsong lets them keep feeding without looking up as often.