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.
A lone eagle feather is believed to convey great power. North American Indians incorporated the eagle's primaries and tail feathers into their ceremonies and legends.
Use of feathers permit. Bald eagles are active during daylight hours (diurnal).
Fidelity - Once paired, bald eagles remain together for life; although if one dies the survivor will not hesitate to accept a new mate.
The wings and soaring - An eagle's wings are long and broad, making them effective for soaring. To help reduce turbulence as air passes over the end of the wing, the tips of the feathers at the end of the wings are tapered so that when the eagle fully extends its wings, the tips are widely separated.
Respiratory system - Eagles have an external naris on both sides of their beak. A bald eagle never reaches speeds that would interfere with normal breathing. An eagle's lungs and air sac system are adequate for its size. Air moves in through the lungs and on into the air sacs before moving back through the lungs and out again. Air passes through the lungs twice with each breath cycle - twice that of mammals.
More about the respiratory system of birds
Immature bald eagle
Bald eagles are larger than golden eagles in average height and wingspan, but there isn't much difference in average weight. One way to distinguish a golden eagle from an immature bald eagle is leg plumage. A golden eagle's legs are entirely feather covered; an immature bald eagle's lower legs are bare. As seen while in flight, juvenile golden eagles have white patches at the base of the primaries; the tail is white with a distinct dark terminal band. It takes four years to acquire adult plumage. Adult golden eagles are brown with tawny on the back of the head and neck; tail faintly banded.
Until 1995, the bald eagle had been listed as endangered under the Endangered Species Act in 43 of the 48 lower states, and listed as threatened in Wisconsin, Minnesota, Michigan, Washington and Oregon. In July of 1995, the US Fish and Wildlife Service upgraded the status of bald eagles in the lower 48 states to "threatened."
On June 28, 2007 the Department of Interior took the American bald eagle off the Endangered Species List. The bald eagle will still be protected by the Migratory Bird Treaty Act and the Bald and Golden Eagle Protection Act. The Bald Eagle Protection Act prohibits the take, transport, sale, barter, trade, import and export, and possession of eagles, making it illegal for anyone to collect eagles and eagle parts, nests, or eggs without a permit. Native Americans are able to possess these emblems which are traditional in their culture.