They have to learn how to hunt, and they only have the remainder of the summer to learn. After that, they're on their own. The first winter is the most dangerous and difficult part of an eagle's life. Higher predators are born with instincts that urge them to fly, to bite or to pounce, but precisely how to do these things is another matter. Through months of trial and error, eagles acquire basic skills such as lighting on perches or stooping on prey through practice.
Eagles practice with almost fully developed bodies, and so sharpen their skills quickly.
The immature bald eagle, such as seen here, is sometimes mistaken for a golden eagle. However, young bald eagles have more white mottled into their coloration overall, and they have the yellow beak of the adult. The golden eagle is more solid in color, and it has a beak that is more blue-black, with a nearly black tip. Eagles molt in patches, taking almost half a year to replace feathers, starting with the head and working downward. Not all feathers are replaced in a given molt.