(Molly Gallagher) The gray squirrel (native to North America, introduced to Great Britain, Ireland, and South Africa) usually lives about three years. It can live ten years and, in captivity, up to 15 years.
Gray Squirrels Live Three Years
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JUNE 30, 2008
April Holladay, www.WonderQuest.com

Q: What is the normal life span for a southeastern gray squirrel?
— Gwen, Virginia Beach, Virginia
Q: How about for the common gray squirrel?
— Gary, Spokane, Washington
A: The gray squirrel (native to North America, introduced to Great Britain, Ireland, and South Africa) usually lives about three years. It can live ten years and, in captivity, up to 15 years.
By the way, the gray squirrel’s hind legs are double jointed and it can leap horizontally 20 feet (6 m).
Further Reading:
Molly Gallagher, Licensed Wildlife Rehabilitator: Eastern Grey Squirrel — how to care for the young
(Answered Sep. 19, 2003; updated June 29, 2008)