Sunday, October 26, 2014

Steller’s Sea Eagle (Haliaeetus pelagicus)

Being a Steller’s Sea Eagle (emphasis on Sea Eagle) these large birds of prey love to gorge on fresh fish and water birds.  On average, they are the heaviest eagles in the world.  Weighing in at anywhere between 11-20 pounds they give the Harpy Eagle and the Philippine Eagle some intense competition in the realm of size.
An adult Steller's Sea Eagle  (photo: The wikipedia files_Markus-Riesenseeadler)
These massive birds have the second largest wingspan of any eagle, which ranges from 6.4 to 8.2 feet.  Females have an average weight of anywhere between 15-20 pounds; males are significantly smaller weighing in around 11-13 pounds on average.  In addition, they have a very large skull and bill; their skull and culmen (upper ridge of a bird’s beak) measuring the largest among eagles.
The Steller's Sea Eagle has a massive beak (photo: The wikipedia files_Greg Hume)
This Eagle has dark plumage covering the majority of its body and high contrasting white on parts of its upper-wing coverts, under-wing coverts, thighs, and under-tail coverts.  Many adults have an extremely bold pied (meaning black and white) coloration.  This raptor has a distinct tail that is relatively longer than those of the White-tailed Sea Eagle and is structured in a wedge-like shape (center tail feathers longer than outer ones).  Like many eagle species they have yellow colored eyes, bills, and feet.  Nestlings have significantly lighter plumage, which is mostly white though it does not take long for their juvenile brownish-grey plumage to start appearing.
Another view of that massive beak (photo: The wikipedia files)
Steller’s Sea Eagles are known to make a deep barking cry, ra-ra-ra-raurau, when they find themselves in an aggressive interaction.  White-Tailed Sea Eagles have a similar call although the Steller’s call is much deeper.
Steller's Sea Eagle with fish (photo: The wikipedia files)
It has been observed that Steller’s Sea Eagles may favor pink salmon and chum salmon, which are sometimes supplemented by grayling and three-spined stickleback (both northern river fish species).  This species of eagle prefers to hunt almost exclusively in shallow water where they hunt active spawning rivers in August and September. In winter, once spawning season has died down, their main diet becomes leftover dead salmon and carrion as they start to move inland.  To see a video of Steller’s Sea Eagles in action Click Here

Steller’s Sea Eagles are classified as Vulnerable by the International Union for Conservation of Nature.  Their total population is estimated at 5,000 and is continuing to decrease.  In areas such as Japan they are regarded as a “National Treasure” and are legally protected.  The factors that threaten their survival include habitat alteration, industrial pollution, and over-fishing.

To see close relatives of this magnificent sea eagle come out and visit the World Bird Sanctuary and stroll down the path just beyond the hospital to many of our Bald Eagles and our beautiful White-tailed Sea Eagle, Cousteau.  The World Bird Sanctuary is open 363 days of the year (barring inclement weather closings).  For directions and hours Click Here.    

Submitted by Callie Plakovic, World Bird Sanctuary Outreach Coordinator

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