Gray Squirrel Have you ever wanted to climb trees as fast as a gray squirrel can? The gray squirrel is the state mammal of North Carolina. The gray squirrel is a very invasive species. Gray squirrels need to drink lots of water, but it needs to be clean water so that they can stay healthy. Gray Squirrels live from 1-2 years at birth, but an adult typically lives until the age of 6. Only a few gray squirrels live to be 12 years old.