What are beavers called before they are full grown? They are called kits. The word applies to young beavers of both the North American beaver (Castor canadensis) and the Eurasian beaver (Castor fiber).
Beaver kits are born after a gestation of roughly three to four months, usually in spring or summer. Unlike many rodent newborns, they are precocial: they have fur, their eyes open within days, and they can swim relatively soon after birth. A litter may contain as many as four kits.
For their first month or two, kits remain mainly inside the family lodge. They nurse for up to about three months, although they can begin eating solid food during their second week. Parents and older siblings bring food and help protect them. After their first year, young beavers often assist with repairing dams and lodges.
A common mix-up is assuming “kit” refers only to a young cat or fox. It is also the established zoological term for a young beaver. Beavers generally reach sexual maturity between about 1.5 and 3 years, after which they may leave to establish their own territory.