A Steller's Sea Eagle (Haliaeetus pelagicus) was seen recently on the Restigouche River near Tide Head. Not only is this a 'mega rarity' for New Brunswick, it is a 'mega rarity' for North America! This bird is supposed to be in Russia or Japan. What is it doing here?
On June 28, 2021 a Listuguj ranger, Gerry Isaac, was out on the Restigouche River. Among the 50-plus eagles present in that part of the river he spotted one that looked decidedly different. He alerted a fisheries warden, Forest Condo, and local official and bird 'expert', Andrew Olive, and they confirmed that what they were seeing was a Steller's Sea Eagle. Photos were difficult to capture but the ones you see in this blog were taken by Andrew Olive. (Thank you, Andrew). Word spread rapidly to astounded birders in both New Brunswick and Quebec. Most of us, no, all of us had hardly heard of this species and certainly didn't know much about it.
Unfortunately the bird was difficult to see and only a few birders got to see it. I was one of the many disappointed. On the morning of June 30, the bird was visible from the north shore of the Restigouche River at the Broadlands Camp Ground and a few got to see and photograph it. Unfortunately the owner of the campground expelled the birders from his property so it made it difficult for others later. With many hours of continuous observation the bird was not located for the rest of that day. With diligent observation from many people from the high banks of the river on both the NB and the PQ sides and scoping the treed islands for perched eagles, the Steller's Sea Eagle was relocated from a good vantage point at Morissey Rock Park on the New Brunswick side about 3:00 pm the next day. The eagle was perched on one of the tall hardwoods on the islands and was seen through a telescope by a few birders. Later that day it was relocated perched on a high dead tree on an island upriver from Gillis Island where it remained until dark. The bird was gone the next morning and was not seen again.
The Restigouche is a beautiful river with lots of fish to feed eagles. There is a population of at least 50 Bald Eagles in that general area. There is a series of many islands upriver from Tide Head which are treed and uninhabited. The river moves swiftly over gravel beds among the islands making good fish habitat. That is where the Steller's Sea Eagle was hanging out.
The Steller's Sea Eagle is one of the world's largest avian predators. The Andean Condor, the Lappet Faced Vulture and the Californian Condor are larger (measured in weight and wingspan). The Steller's Sea Eagle is larger than our Bald Eagle. It is the heaviest eagle in the world, with females weighing 6,195 to 9,500 grams (13.66 to 20.94 lbs) and males weighing 4,900 to 6,800 grams (10.8 to 15.0 lbs). Contrast this to the Bald Eagle which weighs 4,325 grams (9.5 lbs). The wingspan of the Steller's Sea Eagle is 1.95 to 2.5 metres (6 ft 5 inches to 8 ft 2 inches). The wingspan of the Bald Eagle is 2.03 metres (6 ft 8 inches). Seen at the long distance we were viewing from, the difference was not that apparent.
The Steller's Sea Eagle is a very large diurnal bird of prey. It is the heaviest eagle in the world but may fall short in size of the Philippine Eagle or the Harpy Eagle depending on how measurements are taken. It is certainly visually striking. The Steller's Sea Eagle's normal range is northeastern Asia where it breeds in the Kamchatka Peninsula of Russia. This far eastern area of Russia around the Sea of Okhotsk and lower Amur River and islands is known for its large populations of Steller's Sea Eagles. About 4,000 of this rare species live there. This species is listed as vulnerable on the International Union of Conservation of Nature Red List of threatened species. The birds spend their winters in the southern Kuril Islands of Russia and in Hokkaido in northern Japan. So, they do not inhabit a very large area of the world, not flying very far south in winter and restricting their range to a relatively small area. The species is not known for vagrants but a few have been in North America, and inland in Asia as far as Beijing, China and Taiwan.
As reported by Jim Wilson, a recent issue of the American Birding Association North American Birds (Vol 71, No 2) describes a Steller's Sea Eagle seen and photographed 150 miles inland in Alaska on the Denali Highway last August. That was the first North American record away from the west coast. It remained in the area from August 26 to September 14, 2020. There have been only 14 coastal Alaskan records and one from British Columbia in the last 100 years of record keeping! Mega rarity indeed! But, there was an adult Steller's Sea Eagle seen in Texas (of all places) in March, 2021. The bird was well-documented but vanished. Could our bird be the same bird? Interesting to speculate! Our record is the first east coast Canadian record.
In layman's terms, the Steller's Sea Eagle is a very large eagle with a 'honking big orange bill'. It is black and white (or dark brown and white) like our Bald Eagle but the placement of the colours is different. The Steller's Sea Eagle has a dark head, breast and lower back with white across the forewings which turns under the forward edge of the wings and can be seen in flight. This makes a white 'V' on the back of the perched bird. The tail is white and diamond-shaped but shorter than the white tail of the Bald Eagle. The legs and under-tail coverts are clothed in white feathers on the Steller's Sea Eagle and the legs are shorter than the legs of the Bald Eagle. Some specimens show a tiny spot of white just above the dorsal aspect of the beak. The head in some is lightly streaked with fine silver but this is not noticeable at a distance. The eyes are a light lemon yellow. The feet are the same yellow-orange as the beak and the feet have very large talons and spiculated soles for holding prey. These feet are very powerful and the bird is capable of embedding its talons deeply into human flesh (like the Bald Eagle). The beak may be the largest of any eagle and measures 117 mm (4.6 inches) from the gape to the tip. The vocals of this eagle have been described as a deep barking sound like 'ra-ra-ra-raurau'.
Eagles are members of the Accipitridae family along with hawks. The Steller's Sea Eagle's generic name is Haliaeetus which is shared also by the Bald Eagle. The specific name, pelagicus, is from the Greek word, pelagos, which means 'open ocean'. Its name has changed variously since 1811 when it was first described by Prussian naturalist Peter Simon Pallas. It was given its present name by the International Ornithologists' Union and was named after the German naturalist, Georg Wilhelm Steller. In 1996 a DNA analysis showed the Steller's Sea Eagle diverged from the lineage that gave rise to the Bald Eagle and the White-tailed Eagle about 3 to 4 million years ago.
Steller's Sea Eagles feed mainly on fish but they will also eat gulls and kittiwakes and other water birds. They hunt food by perching and diving down from heights of 30 metres to grab prey from the water or air. In winter they gather around the ice-free areas of northern Japan where they feed on fish, fish offal from the fishing fleet, and gulls. They sometimes gather in large flocks in the 100s. They will also eat crustaceans and mammals. Being such large predators they mostly have their pick of whatever other birds are feeding upon.
Steller's Sea Eagles nest on rocky cliffs on sea islands or in large trees at a height up to 50 metres (150 ft). The nests are built of sticks and twigs. Courtship occurs in February and March and consists of soaring flights. One to three greenish-white eggs are laid and incubated for 39-45 days. Both adults help raise the eaglets. The eaglets fledge in 2 months. With egg predation, nest collapse and nestling predation only about 50% of the eggs are successfully raised. Usually only one chick makes it to adulthood. Adult plumage is attained by year 4. In the wild the life expectancy is 20 years.
What is the status of this species? As mentioned above, it is listed as vulnerable. 320 pairs have been recorded in Kamchatka. There is an additional 89 nesting areas which are not monitored. In the Bay of Penshina over 1,200 pairs breed and 1,400 juveniles occur. A few hundred other pairs in other areas are being monitored. The food base and habitat in the wintering area are secure so far. So the outlook for this species for now is 'favourable'. In Japan this species is protected.
So where now is the Steller's Sea Eagle found on the Restigouche River and is it the bird seen in Texas in March? We have no way of knowing if it is the same bird. As seen in the photos above, 'our' bird did not have a leg band. Is the bird seen here a vagrant or is it a zoo or falconer's escapee? We don't know. Given the fact that vagrants are rare in this species, one cannot predict where this bird came from and where it will go. But it is definitely on the move. On 9 July, 2021, a Steller's Sea Eagle was seen in the Gaspé on the York River. This is many kilometres northeast of where it was found on the Restigouche but it is surely the same bird. We cannot predict whether it will stay there or whether it will keep moving. It will be interesting to hear of future sightings.
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