Birds of Prey: The Steller's Sea Eagle
While those of us in the western hemisphere may not be overly familiar with the Steller’s Sea Eagle, this beautiful member of the eagle family is certainly worth getting to know. When measured by average weight, the Steller’s Sea Eagle is the heaviest bird of prey in the world. Slightly smaller in dimensions than the Harpy Eagle of Central and South America and the Philippine Eagle, the Steller’s Sea Eagle lives in the coastal regions of northeastern Asia.
Description
The sheer size of the Steller’s Sea Eagle is enough to make this raptor one of the most impressive birds in the world. With adult females reaching 15 to 20 pounds, and a wingspan of between six to eight feet, the Steller’s size strikes an impressive and imposing figure. As is typical of birds of prey, the male is much smaller than the female and will weigh from 11 to 13 pounds. Steller’s will range from about 33 inches in length up to as much as 41 inches for the largest adults.
Steller’s Sea Eagles are generally black to dark brown over most of their body. They have very distinctive white feathers on their shoulders, legs, tail and crown. Their eyes, feet, and very large bill, are all a very bright yellow in color and they have the largest skull of any eagle anywhere in the world. Their full adult coloring is not reached until they are approximately five years old, which is when they reach their sexual maturity. Newborn eaglets are initially a very silky white, which quickly turns to a brownish-grey color within a few weeks.
Habitat and Range
The Steller’s Sea Eagle is pretty much confined to northeast Asia in the area around the Kamchatka Peninsula of Russia and the Sea of Okhotsk. Steller's have been found as far south as Taiwan and in North America, but they are considered to be individuals that have wandered from their normal range.
Generally, Steller’s Sea Eagles can be found in one of two habitats: near large rivers and along the sea coast. They prefer areas with large trees for nesting and their nest can be up to five feet deep and eight feet in diameter. In addition to nesting in large trees they will also nest on rocky cliffs. The nests of the Steller’s Eagle are called aeries and a pair will usually return to the same site yearly.
- Orange: breeding only
- Green: resident all year
- Blue: winter only
- Grey: vagrant range
Some, but not all Steller’s will migrate and this seems to be dependent on food availability and sea ice conditions. In the Kamchatka area of Russia many of the eagles will overwinter in the river valleys and forest. Those eagles that do migrate will winter in the southern Kuril Islands and near Hokkaido in northern Japan where they are close to rivers and lakes. They will usually stay until late March to late April before heading back north.
Diet
Steller’s feed on a variety of food but fish is their most common meal. Trout and salmon seem to be their favorite prey. The annual salmon runs are a time for the Steller’s to feast as they compete with brown bears, golden eagles, and other raptors for their favorite meal.
Steller’s will spend a good portion of their day perched high up in a tree as they scan the area for food. With binocular like vision they can spot their prey from a distance before swooping in for the kill. Steller's are powerful enough to catch a fish on the fly and their large talons make for quite the weapon. On occasion they will also hunt small mammals, crabs, other birds, and they are also not opposed to scavenging and stealing food from other raptors.
Reproduction
Steller’s Sea Eagles will lay their eggs in mid-spring after a late winter courtship. They will usually lay between one to three eggs that are a greenish white in color. The eggs will incubate for 40 to 45 days during which time the female will rarely leave the nest. Generally only one chick will survive, but this is not always the case, and occasionally two and even three chicks will be raised successfully. The chicks are born with a white silky down that will quickly change to a brownish-grey color as they quickly grow. It normally takes about ten weeks for the eaglets to fledge and this usually takes place by August or September. It will take about five years for the Steller's Sea Eagle to reach their sexual maturity and full color.
Interesting Facts
- The Steller’s Sea Eagle is named after Georg Wilhelm Steller, a noted 18th-century explorer and zoologist.
- Steller’s are called O-washi in Japan where they are revered and honored.
- They are considered one of the largest of all eagles species along with the Philippine Eagle and the Harpy Eagle.
- A group of Steller’s Sea Eagles is referred to as a “constellation”.
- They are diurnal, meaning they hunt during the day.
- The Scientific name of the Steller’s Sea Eagle is Haliaeetus pelagicus.
- They are unique among all other sea eagles in that they have a bright yellow beak even in juvenile birds.
- Also referred to as the White-shouldered Eagle or the Pacific Eagle.
- Due to nests collapsing under their own weight and egg predation only about half to two-thirds of eggs successfully reach adulthood.
- Steller's Sea Eagles have no natural predators.
Status
Because of their somewhat remote and limited location, not much is known about this eagle, especially during their early years. Current estimates place the population at about 5,000 and they are afforded complete legal protection in Russia. As is usually the case with raptors that are at the top of the food chain, their biggest threat comes from man. Habitat loss and river contamination are constantly putting pressure on this magnificent bird and their population is slowly decreasing despite the protection. Their current status is list as threatened and vulnerable.
Questions & Answers
© 2012 Bill De Giulio
Comments
Hi Bill,
Huge bird, a good fishermen. Its big but very ordinary looking bird i hope to see it in real next month when i visit japan. Maybe that's the time where i can totally say if its ordinary looking or far more impressive than any other fish eagles.
Thanks Bill
Are they even larger than the phil eagle in size?
Hi Bill, just curious to know is these eagle larger than the harpy in size?
Nice blog jerry....this bird look like a"zumo wrestler of the eagle world."
thanks bill .....ur smart as well as ur so kind and respecfull..... happy holidays......
thanks for the reply i really appreciate ur effort...to be honest with u of all the blogs i have read about eagles ur blog is the most accurate for me especially when in terms of facts im just confused only in one part of the facts about stellar that it is considered the largest and the most powerful of all eagle specie. by the way i try to visit panama last year i have seen harpy eagle and its huge bird the largest in their foundation is a female weighting 8 kgs 106 cm and 7 feet wingspan. in davao phil the largest now is 10 kgs 110 cm 8.9 wingspan. ive seen stellers twice in japan. as i compare their size the phil eagle is the largest and u are correct. only the weight is a big ? because as i ask the caretaker the food in the center is being controlled for reproduction purposes. they are not after of claiming their eagle as the largest in the world but to preseve it. i tru to ask some of experts if u feed the phil eagle with abundant food supply how much is the weight it can attain they said it can weigh more than 13 kgs i just don't know how true it is, but that's rediculous to make just to take the title of the largest better to protect it and help preserve to the next generations. when in terms of beauty i agree with u that bird is the most handsome eagle in the world if somebody have a chance to see it in personal a big wow believe it or not its headress is so fantastic. according to david attenbourough its headdress is flbouyant crown that outclasses all other eagles on the world..it looks like a lion mane i can't just imagine im in a prehistoric era....the eyes and beak is bluish really caugh my attention i ve never seen a bird as beautiful as that. the beak is as big asy palm..menacing looks but very majestic....thanks bill looking forward for more of your blogs...
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For everybody's information the stellers eagle is not the largest and most powerful of all eagle specie in the world as what is stated in the facts above. Indeed on average they are the heaviest eagle in the world. Tha largest eagle in the world on terms of total size is the philippine eagle. The harpy eagle is one of the largest specie of eagle in the world, the philippine eagle is the only living eagle to surpass it in size hence it is larger than the harpies. According to experts the strongest and the most powerful eagle belongs to forest eagle they are the phililppine eagle and the harpy eagle both have the strongest feet and claws as large as that of agrizly bear capable of killing adult mongkey, sloths, deers, large reptiles like monitor lizards pythons and cobras. Wild and domesticated pigs, cats, and dogs stand no chance to these two eagle. They can pop out a monkey skull or even crush a human bone. The stellers are fish eagles feed mainly on fish and it is not the strongest and most powerful eagle in the world. Please make a correction to your facts... thanks
For everybody's information the stellers eagle is not the largest and most powerful of all eagle specie in the world as what is stated in the facts above. Indeed on average they are the heaviest eagle in the world. Tha largest eagle in the world on terms of total size is the philippine eagle. The harpy eagle is one of the largest specie of eagle in the world, the philippine eagle is the only living eagle to surpass it in size hence it is larger than the harpies. According to experts the strongest and the most powerful eagle belongs to forest eagle they are the phililppine eagle and the harpy eagle both have the strongest feet and claws as large as that of agrizly bear capable of killing adult mongkey, sloths, deers, large reptiles like monitor lizards pythons and cobras. Wild and domesticated pigs, cats, and dogs stand no chance to these two eagle. They can pop out a monkey skull or even crush a human bone. The stellers are fish eagles feed mainly on fish and it is not the strongest and most powerful eagle in the world. Please make a correction to your facts... thanks
What a beautiful bird! What a beak it has! All the better to catch his prey, I'm sure. I always love your "Bird of Prey" hubs, they are my favorites! This is just as awesome as the rest. You always do such a good job. The video is awesome too. Voting up and what else...awesome! :) Pinning too!
I completely agree, well written hub! You're very talented and your reasoning is impeccable, keep up the outstanding work and can't wait to read more from you! Cheers!
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Absolutely delightful, Bill! You definitely are the Birdman of Hubsville! Well-researched, excellently written, and generously complemented with great media. Thank you for sharing!
Up and awesome. This is a glorious hub. There is one of these beautiful birds at the National Aviary here in Pittsburgh. They are huge and I love to look at their talons. Thanks for this hub.
I voted up, clicked interesting and useful. This is a good information about the bird.
The bird is also similar to our Philippine Eagle or the monkey-eating eagle.
You have a knack for presenting a great deal of information in a way that is by no means overwhelming. Great work here on a beautiful bird. Vote up, useful, and sharing too.
This hub starts with a very impressive photo, Bill, and the hub is very interesting! These birds are huge. I'd love to see them in the wild.
What a gorgeous eagle. I would love to see one and wouldn't mind doing extended research on a family of birds.
Sheez, I have never heard of this bird. It is huge. The picture of that guy holding one....the bird dwarfs him! Great information, Bill.
Beautiful! These birds are beautiful and you've done a fantastic job of introducing them....I say 'introducing' because I didn't know about them. Your facts are very revealing and this whole thing is well written. Thanks so much.
Voted up, useful, beautiful and interesting.
I always enjoy learning about new things. This was most interesting and creates an awareness of the miracles of nature. Great hub. Voting UP++++
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