Reproduction:

Eagles reach sexual maturity at around four or five years of eagle, when they form what are known as "breeding pairs." Much like a marriage (although maybe not so much in this day and age), the two eagles mate for life. Once one mate dies, the other finds a new mate rather quickly, and it is not completely understood if the relationship is strictly monogamous.

How do these pairs form? There are many ways that bald eagles communicate with each other. These courting rituals range from the ordinary mating calls to spectacular aerial displays. The more interesting aerial displays seem to the standard observer as reckless and very dangerous, but nonetheless, eagles take part it them. The most harmless of the aerial courtships involve two eagles pursuing each other through the sky sometimes even flying under each other upside-down while touching talons. When involved in the ritual, the eagles look as though they are playing a game of aerial "Cat and Mouse." The most impressive of the courtships is called the "cartwheel display" during which the two eagles will fly to great altitudes and lock talons, only to tumble down to the earth, seemingly out of control, until they reach a certain point and they release each other and fly away.

The purpose of these displays seem to be to establish or renew a pair bond and are usually the precursors to sexual intercourse.

For more images of courtship rituals from this set click here. Images courtesy of Doug Bolt

After the courting and once the female is ready for sexual intercourse, she will return to her nest and call for her mate. Upon arrival the eagle assumes a "solicitation" position. This position involves the female flattening herself out with her tail lifted slightly in the air.  The male then mounts the female, careful not to harm her with his razor sharp talons and begins copulation. The entire act of copulation can be over in as quickly as five seconds or last up to several minutes, and can occur several times a day. The average number of eggs laid is from one to four per mating season.

Bald Eagle eggs are fertilized internally before they are laid in the nest. The term for laying eggs rather than housing them internally is oviparity. Being oviparous has several advantages including increased mobility, increased clutch size (number of eggs produced), less energy required. One major disadvantage is that the eggs run a significant chance of being discovered and harmed by other organisms. In order to protect the eggs, both male and female eagle play a roll in guarding the eggs. However, the female spends more time incubating the egg during the thirty-five day period until hatching occurs. The young eaglets will stay in the nest until about 3 months of age, when fledging occurs, which can be read about in other portions of this website.

A young eaglet in nest