The bald eagle's lifespan begins when the birds hatch from eggs in a gigantic nest on a cliff or in the branches of a tall tree. NHPTV.org states that bald eagles generally produce two or three eggs at a time. These eggs hatch five to six weeks after they are laid.
Bald eagle pairs are monogamous and mate for life. They use the same nest throughout their lives, according to NHPTV.org. Each time they return to their nest, they add new sticks. The Virginia Department of Game and Inland Fisheries states that over time, these nests get quite large and tend to reach five to six feet in diameter. These devoted hard-working parents raise their chicks as a team, a process that takes roughly five months.
Bald eagles reach sexual maturity between four to five years old. At this point, they tend to return to their place of birth to find a mate. Courtship involves elaborate stunts in the air, including one where the two eagles lock talons and fall with their wings outstretched, then split apart just before they crash.
The average lifespan of the bald eagle is 20 years. Adult mortality is low, as bald eagles are a protected species, but only about half of newborn bald eagles survive their first year.