Squirrel Ageing & Longevity
Squirrels can be difficult to age and many observers simply group them into juveniles (up to six months old), subadults (six months to one year) and adults (one year plus) based on the colour of the fur around the genitals, swollen mammae, fur pattern, density and pigmentation of the fur. Juvenile animals have sparser fur than adults and the tail hair is short and dense. Body weight can also be an accurate separator.
In the laboratory, age can be determined by sectioning the teeth; a broad opaque layer of cementum is deposited in the roots of the molars during the summer, with a narrow dark band forming during the winter.
In the wild, Red squirrels are known to live for up to seven years, although three appears more typical. The oldest captive Red squirrel that I am aware of was a male that lived to 15 years old at Asahiyama Zoo in Japan.
The upper age limit for Grey squirrels in the wild is probably around nine years, although tracking and observational data suggest that few individuals exceed four or five, especially males. Indeed, population studies conducted by John Gurnell in southern England during the early 1980s found females here lived longer on average than males – typically four to five years, and up to seven, compared with two to three years, and up to five, for males. There are, however, unconfirmed reports of animals surpassing this figure by a considerable margin. In February 2026, Verna Slade sent me a photograph of a squirrel she has named "Strawberry", which first began visiting her property in Atlanta, Georgia, as a juvenile during August 2000. According to Verna, she has developed a notably trusting relationship with Strawberry and numerous other squirrels that visit her property most days to feed. Despite being nearly 27 years old at the time of writing, Strawberry reportedly remains in good condition and, to my knowledge, currently represents the oldest unconfirmed record for the species. The oldest confirmed captive specimen on record was an individual of unknown sex held at Racine Zoo, Wisconsin, which survived to 23 years and 6 months.
