A newborn squirrel looks nothing like the bushy-tailed acrobat you see raiding bird feeders. At birth, most tree squirrels are pink, hairless, and roughly the size of a human thumb, with sealed eyes, closed ear flaps, and no visible teeth. They resemble tiny, wrinkled rodents more than anything a casual observer would recognize as a squirrel. The transformation from this naked, helpless state into a fully furred juvenile takes several weeks, and each stage has distinct visual markers that make it possible to estimate a baby squirrel’s age just by looking at it.
The First Days After Birth
Eastern gray squirrels, the species most people in North America encounter, are born after a gestation of about 44 days. A newborn weighs roughly 14 to 18 grams and measures around 5 to 6 centimeters from nose to rump, not counting the tail. The skin is translucent pink, and you can sometimes see the dark shadow of internal organs beneath it. There is no fur at all. The tail is a thin, flat appendage with no fluff or bushiness to it. The ears are tiny flaps pressed tightly against the head, and the eyes are sealed shut under a thin membrane of skin. Toes are fused together and only partially separated. In short, a squirrel born minutes ago looks more like a bean with legs than a squirrel.
Fox squirrels, which are larger as adults, produce slightly bigger neonates, but the overall appearance is the same: pink, blind, and hairless. Red squirrels, being smaller species, have proportionally tinier babies. Across tree squirrel species, though, the newborn template is remarkably consistent. They are altricial animals, meaning they are born in an undeveloped state and depend entirely on the mother for warmth, food, and protection during the first weeks of life.
How Fur Comes In
The first hint of fur appears within the first week as a faint darkening or “shadow” on the skin, most visible along the back and on top of the head. This is pigment developing beneath the surface before actual hair shafts emerge. By around 10 to 14 days old, a fine fuzz of fur begins to cover the dorsal side of the body while the belly remains mostly bare and pink. The coloring at this stage already hints at the adult pattern: gray squirrel babies show a grayish tint, while fox squirrel babies lean toward warmer reddish-brown tones.
By three weeks, the fur is noticeably thicker on the back and sides but still thin enough that the skin shows through in places, especially on the belly and inner limbs. The tail is getting longer but remains flat and ratlike, with only sparse, short hairs. It does not look bushy yet. Around four to five weeks, the body fur is mostly filled in across the torso, and the belly finally starts to catch up. The underside fur tends to be lighter, a pattern that persists into adulthood.
The tail is the last part to achieve its signature look. Full tail fluffiness does not develop until the squirrel is well past six weeks old, and the tail continues filling out over the following weeks. If you find a small squirrel with a flat or scraggly tail, that is a strong indication it is still quite young.
When the Eyes and Ears Open
Eye opening is one of the most reliable age markers. In eastern gray squirrels, the eyes typically open between four and five weeks of age. Before that, the eyelids are sealed shut, and the baby navigates its nest entirely by touch and smell. You may notice slight bulging under the eyelids around three weeks as the eyes develop, but they do not crack open until later. When they first open, the eyes often look dark, slightly cloudy, and oversized relative to the head.
The ears develop on a slightly different schedule. The ear pinnae, the external flap portion, begin to separate from the head and stand upright at around three to four weeks. Before that, the ears are folded flat and effectively sealed, meaning the baby cannot hear airborne sounds well. Once the ears open and stand erect, the baby starts responding more actively to sounds in its environment, flinching at loud noises or turning toward the mother’s calls.
These milestones vary somewhat across species. Subtropical and tropical tree squirrels tend to reach developmental stages earlier, with nestling periods as short as 18 to 27 days compared to 35 to 58 days for tree squirrels in northern climates.1Oxford Academic (Journal of Mammalogy). Postnatal Development and Growth of Southern African Tree Squirrels in the Genera Funisciurus and Paraxerus This means a three-week-old squirrel in a subtropical species may be further along developmentally than a three-week-old gray squirrel in Pennsylvania.
Teeth and Feeding Changes
Baby squirrels are born without visible teeth. The lower incisors are the first to erupt, usually appearing around three weeks of age as tiny, sharp nubs. The upper incisors follow at about four to five weeks. These are important milestones because they correspond roughly with the period when the baby begins transitioning from exclusive nursing toward exploring solid foods. A baby squirrel with lower incisors but no uppers is likely around three to four weeks old.
Even after teeth appear, baby squirrels continue nursing for several more weeks. Weaning in gray squirrels does not typically occur until eight to ten weeks of age. During the transition period, you might see juvenile squirrels awkwardly gnawing on nuts or seeds they are not yet capable of fully processing. Their jaw muscles and incisors are still growing, and they cannot crack hard shells with the efficiency of an adult.
How to Estimate Age by Appearance
If you find a baby squirrel on the ground, its appearance gives you a rough developmental timeline. Here is what to look for at each stage:
- Newborn to one week: Completely hairless and pink. Eyes and ears sealed. Tail thin and bare. Body length around 5 to 6 centimeters without the tail. Weighs under 20 grams.
- One to two weeks: Faint fur shadow visible on the back. Skin may start to darken. Still blind and deaf. Toes beginning to separate.
- Two to three weeks: Short, fine fur on the back and head. Belly still mostly bare. Lower incisors starting to erupt. Ears beginning to lift away from the head.
- Three to four weeks: Fur covers most of the body but is still thin. Ears standing upright. Eyes still closed but may look puffy. Tail growing longer but remains flat.
- Four to five weeks: Eyes open. Fur is well developed on the body. Tail starting to show some fluffiness. Upper incisors emerging. Beginning to look recognizably like a squirrel.
- Six to eight weeks: Fully furred. Tail becoming bushy. Active and alert, beginning to move around outside the nest. Still nursing but may nibble on solid foods.
- Eight to twelve weeks: Approaching juvenile size. Fully weaned or nearly so. Tail fully bushy. Independent movement and foraging behavior developing.
These timelines apply primarily to eastern gray and fox squirrels. Other species have their own pace, with smaller species often developing faster and larger ones taking longer to reach adult proportions.1Oxford Academic (Journal of Mammalogy). Postnatal Development and Growth of Southern African Tree Squirrels in the Genera Funisciurus and Paraxerus
Telling a Baby Squirrel from Other Animals
A hairless, pink baby squirrel can be surprisingly hard to identify. People often confuse very young squirrels with baby rats, baby rabbits, or even baby chipmunks. A few features help sort them out.
Baby rats are born hairless and pink in a similar way, but their tails are long, thin, and scaly from the start. A newborn squirrel’s tail is short relative to its body and does not have the pronounced scaliness of a rat tail. Also, squirrel babies tend to have proportionally larger heads and shorter snouts than rat pups of comparable age.
Baby rabbits, or kits, are also born blind and helpless, but even at birth they have a thin covering of very short fur. Their ears are much longer relative to their head than a baby squirrel’s, and their hind feet are disproportionately large. A hairless baby with small ears and roughly equal-sized front and back feet is almost certainly a squirrel or a rat, not a rabbit.
Chipmunks, which are closely related to squirrels, produce babies that look extremely similar at the youngest stages. The main difference becomes apparent as fur grows in: chipmunk babies develop their distinctive dorsal stripes by around two to three weeks, while squirrel babies develop a more uniform coat. If you are trying to identify a very young hairless baby, the species may not be distinguishable by eye until some fur appears.
Why Baby Squirrels End Up on the Ground
Most people asking what a baby squirrel looks like have found one, or think they might. Understanding how they end up displaced helps you respond appropriately. Squirrel nests, called dreys, are built high in tree canopies or inside tree cavities. Babies can fall out during windstorms, when the mother is moving them between nests, or when a predator disturbs the nest. Sometimes tree trimming or construction dislodges a nest entirely.
A baby squirrel on the ground is not always orphaned. Mothers frequently retrieve fallen babies if given the chance. If the baby is warm, uninjured, and in a safe spot, the standard advice from wildlife rehabilitators is to place it at the base of the nearest tree in a small open box and monitor from a distance for several hours. The mother will often come back. She can carry babies one at a time in her mouth, gripping them by the belly while they instinctively curl up to make themselves easier to transport.
If the baby is cold, lethargic, injured, or if the mother has not returned by late afternoon, that is when human intervention becomes appropriate. Very young squirrels, those under four weeks, cannot regulate their own body temperature and will become hypothermic quickly on the ground, especially in cooler weather. Warming the baby gently and contacting a licensed wildlife rehabilitator is the recommended course. Cow’s milk and most human infant formulas are not appropriate for squirrels and can cause fatal digestive problems.
Growth Rate and the Road to Independence
Baby squirrels grow fast. A gray squirrel that weighs about 15 grams at birth can reach 100 grams by four weeks and 200 grams or more by eight weeks. The growth rate during the nursing period is steep, driven by the mother’s rich milk, which is high in fat and protein compared to the milk of many other rodents. The body grows fastest in the first six weeks, while the tail and ears continue proportional growth for longer.
Squirrels begin venturing out of the nest around six to seven weeks, making short, clumsy trips along nearby branches. They are recognizably squirrel-shaped at this point but noticeably smaller than adults, with slightly oversized heads and thin, still-filling tails. Their movements are uncoordinated compared to adults, and they often freeze on tree trunks rather than executing the smooth spiraling escape maneuvers that adult squirrels perform instinctively.
By about ten to twelve weeks, juveniles are weaned and beginning to forage independently, though they may stay near the mother’s territory for a while longer. Full adult size is reached somewhere around nine months to a year, depending on the species and food availability. The juveniles that disperse from the natal territory face the highest mortality rates, as they are inexperienced foragers navigating unfamiliar areas with established territorial adults and predators.
Color Variations in Baby Squirrels
Not every baby squirrel grows up gray or brown. Melanistic (black) and leucistic (white or pale) variants occur regularly in gray squirrel populations. Black squirrels are particularly common in certain regions of the midwestern and northeastern United States and parts of Ontario. These color variants are genetic, and a melanistic baby will show darker pigmentation in its skin even before fur grows in. The fur that emerges will be uniformly dark rather than the banded gray pattern of the typical morph.
Albino squirrels, which lack pigment entirely, are born with pale pink skin and develop white fur with pink or red eyes. They are rare but notable enough that several towns in the United States have become locally famous for their white squirrel populations. Some of these are true albinos while others are leucistic, meaning they have reduced pigment but retain some color in the eyes.
Fox squirrel coloration is even more variable geographically. Babies from populations in the southeastern United States may develop strikingly dark coats with white noses and ears, while those from midwestern populations tend toward the more familiar orange-brown. The coat pattern that eventually develops is already genetically determined at birth, even though the hairless newborn gives no outward sign of it beyond subtle differences in skin pigmentation.
Ground Squirrel and Flying Squirrel Babies
The description above focuses on tree squirrels because those are the species most readers encounter, but the squirrel family is large, and babies of other species look somewhat different. Ground squirrels, including the familiar thirteen-lined ground squirrel and various rock squirrels, are also born hairless and blind. Their overall proportions differ slightly from tree squirrels: ground squirrel babies tend to have shorter tails and more robust bodies relative to their length. Once fur grows in, ground squirrel species often display spotted or striped patterns that distinguish them easily from tree squirrels.
Flying squirrel babies are among the smallest in the squirrel family. Northern flying squirrels, found across much of Canada and the northern United States, produce newborns weighing only about 5 to 6 grams. These babies are hairless and pink like other squirrel neonates, but they are notably smaller and have proportionally larger eyes even when the lids are still sealed. The patagium, the loose flap of skin that stretches between the front and hind legs to enable gliding, is present at birth but lies flat against the body and is difficult to see until the baby grows. Flying squirrels are nocturnal, so people rarely encounter their young, but anyone who opens an attic nest box and finds impossibly tiny pink babies with big bulging eye bumps is likely looking at flying squirrels.
Prairie dogs, which are technically ground squirrels despite their common name, have relatively large litters and are born in underground burrows. Their babies are similarly hairless at birth but develop fur and open their eyes on a schedule roughly comparable to other ground-dwelling species. Because prairie dogs are colonial, multiple litters may share a burrow system, making it possible to find babies of slightly different ages clustered together underground.