A baby beaver is called a ‘kit’. Sometimes in historic records you will see it called a kitten. Babies are born fully furred with their eyes open. They can swim right away but need help learning how to dive, since they bob like corks in the water. This means they can’t leave the lodge or return through the plunge hole without some help.
Note: If you ever find a beaver this size wait to see if it gets taken home or bring it to a rehabber yourself! The beaver in this video is way to small to find his way home safely.