Why do Bald Eagles have such big, strong nests when they have only two small eggs? Bald Eagles are about 3 feet (90 centimeters) from their head to their tail and before the nestlings leave the nest, they become as large as their parents and need a lot of room for their 6 foot (1.8 metre) wingspan.dult Bald Eagles have white heads and tails and dark brown bodies. They have large yellow feet with sharp talons and a large yellow beak and yellow eyes.