Female Squirrel Difference. Most female gray squirrels begin their reproductive life at 1.25 years of age but can bear young as early as 5 and a half months. Squirrels grow to maturity in one year.
Observe the behavior of the squirrels.
Male and female arctic ground squirrels differ in their timing of seasonally recurring life cycle the researchers attribute this difference in work ethic to the amount of food the females needed to. Tree squirrels can be found in almost any land area on the planet, so they must be good at identifying each other's gender. If you see them in couples, the most 'aggressive' one is usually. Before that, they mostly stay hidden from view.