Steller’s Sea Eagles (Haliaeetus pelagicus) are large, monogamous birds that breed once a year, typically from February through August. They are native to eastern Russia, specifically the Sea of Okhotsk and the Kamchatka Peninsula, and are frequent winter migrants south to the Japanese Islands of Kuril and Hokkaido.

Breeding Behavior of Steller’s Sea Eagles

During the breeding season, Steller’s Sea Eagles form pairs and spend the entire breeding season together, from around February to August. They build nests, known as eyries, on rocky cliffs or in large trees out of thick branches, and can reach a size of two meters across.

Nest Building and Egg Laying

The average clutch size is 2, but ranges from 1 to 3. The egg-laying period normally lasts from April through May, and the typical incubation period is 38 days. Eggs hatch between May and June, with fledging taking around 70 days. Chicks leave nests by August or September.

Parental Care

Both parents contribute to raising offspring to independence, but little is known about the specifics of their parental investment. Steller’s Sea Eagles are solitary birds, congregating with others only to breed, and are commonly seen perching on cliffs above the sea or in large trees. They are active during the day and migrate to warmer areas in the winter.

Mating Behavior of Steller’s Sea Eagles

Image source: stellers sea eagle

In terms of mating behavior, Steller’s Sea Eagles engage in a display called “cartwheeling,” where they soar high above the breeding area while calling. This display is used to secure breeding territories and attract a mate.

Pair Bonding and Territoriality

Steller’s Sea Eagles are generally imprinted on their own species and will not see a different species as a potential mate. A notable case of Steller’s Sea Eagles breeding with a different species was reported near Juneau, where a Bald/Steller’s pair was together for 10 years. However, this is not a common occurrence.

Conclusion

In summary, Steller’s Sea Eagles are large, monogamous birds that breed once a year, typically from February through August. They build nests on rocky cliffs or in large trees, and both parents contribute to raising offspring to independence. Steller’s Sea Eagles engage in a display called “cartwheeling” to secure breeding territories and attract a mate, and they are generally imprinted on their own species.

References:
– Reddit post on Steller’s Sea Eagles
– Animal Diversity Web entry on Steller’s Sea Eagle
– AnimalSpot.net page on Steller’s Sea Eagle