Golden eagles are monogamous, and pairs may breed together for several years. In sedentary populations, pairs stay together year round. Golden eagle courtship includes the pair flying together, chasing, diving and pretending to attach each other.
Mating System: monogamous
Golden eagles breed between March and August. Some golden eagles are sedentary, remaining in the same territory all year. These eagles may begin building their nests and forming pairs as early as December. Migratory golden eagles don’t begin pair formation and courtship until they return to the breeding grounds in early spring. Many pairs re-use the same nest for many years. Golden eagles usually build their nests on cliffs, but may also use trees, riverbanks and man-made structures, such as windmills, observation towers, nest platforms, and electrical towers. Nests are built 0 to 107 m off the ground. The male and female both build the nest. This takes 4 to 6 weeks. Nests are made of sticks and lined with soft vegetation, such as grasses, dry yucca leaves, inner bark, dead and green leaves, mosses and lichens. Some golden eagle nests are huge. The largest nest was 6.1 m tall and 2.59 m wide.
The female lays 1 to 4 (usually 2) eggs. She lays one egg every 3 to 4 days. The female incubates the eggs for 35 to 45 days (average 42 days). The chicks hatch several days apart, and are helpless (altricial). The older nestlings are usually much larger than the younger nestlings, and the older, stronger eaglets often kill the smaller chicks. The female parent broods the chicks regularly for up the first 45 days or so. Both parents bring food to the nestlings. The nestlings begin to leave the nest when they are 45 to 81 days old. They first leave the nest by walking, hopping or falling out of it. They begin to fly when they are about 10 weeks old, and become independent from their parents 32 to 80 days after fledging. Golden eagles begin to breed when they are 4 to 7 years old.
Breeding interval: Golden eagles breed once yearly.
Breeding season: Golden eagles breed from March through August, depending on their geographic location.
Range eggs per season: 1 to 4.
Average eggs per season: 2.
Range time to hatching: 35 to 45 days.
Average time to hatching: 42 days.
Range fledging age: 45 to 81 days.
Range time to independence: 32 to 80 days.
Range age at sexual or reproductive maturity (female): 4 to 7 years.
Range age at sexual or reproductive maturity (male): 4 to 7 years.
Key Reproductive Features: seasonal breeding ; gonochoric/gonochoristic/dioecious (sexes separate)
Average eggs per season: 2.
The female golden eagle of a pair does most of the incubation. She also broods the chicks much of the time for the first 45 days after hatching. Both parents bring food to the nest, but the male provides more food than the female.
Parental Investment: altricial ; pre-fertilization (Provisioning, Protecting: Female); pre-hatching/birth (Protecting: Male, Female); pre-weaning/fledging (Provisioning: Male, Female, Protecting: Male, Female); pre-independence (Provisioning: Male, Female, Protecting: Male, Female)