Sea Eagle Elucidation: 5 Essential White-Tailed Eagle Facts

There is no one eagle species that specializes in Arctic living in the manner of, for example, the snowy owl among owls, the polar bear among ursids, and the beluga and narwhal among toothed whales. But a few of the water-loving species known as the sea eagles do indeed range up into the subarctic and, to some extent, into the Arctic proper, and wherever they’re found they exert a major ecological influence as a top-level predator and enthusiastic scavenger.

“Sea eagle,” in the manner of many common (versus Latin or scientific) names of organisms, is rather loosey-goosey nomenclature, as it seems to imply a firmly marine-connected bird. In fact, many sea eagles—raptors of the subfamily Haliaeetinae, to be specific, which can be found on all continents save for South America and Antarctica—are indeed big fans of coastal-living, but they also happily range far inland, thousands of miles away from seacoasts. That said, such interior sea eagles still tend to associate with aquatic habitats of one kind or another: from large rivers to lakes and wetlands. This speaks to their overall fondness for open water and food of the fishy and feathered variety (though, here again, there are many exceptions).

Although a couple of other sea eagles brush against the southern fringes of the Arctic proper (as we’ll talk about shortly), it’s the majestic and commanding white-tailed eagle—also known as the erne—which’ll be the main focus of this article on account it shows up the most in the vicinity, and even north, of the Arctic Circle. Let’s dive into some essential white-tailed eagle facts!

Soaring gracefully through the winter air, the magnificent White-tailed Eagle embodies the wild spirit of the northern skies. Learn more about these incredible birds!

(1) Three Species of Sea Eagle Range Into the Subarctic & Arctic

The white-tailed eagle belongs to a genus of sea eagles, Haliaeetus, which includes two close relatives—the bald eagle of North America, often considered a “sister species” of the white-tailed, and the Steller’s sea eagle of far eastern Asia—as well as the the more distantly related Pallas’s sea eagle of central and southern Asia.

Of the three northern Haliaeetus sea eagles, the Steller’s has the most restricted range, being found along the Pacific coast of the Russian Far East (its primary breeding grounds) and on wintering grounds in the northern Japanese island of Hokkaido, the Korean Peninsula, and parts of northeastern China. Its northern range along the Sea of Okhotsk and on islands in the Bering Sea takes it into the subarctic. The bald eagle, meanwhile, is broadly distributed in North America, where it’s endemic, and ranges north of the Arctic Circle in Alaska and northwestern Canada, though it’s primarily found from the boreal forest/taiga southward.

The white-tailed eagle claims the largest range of the Haliaeetus sea eagles: It’s found from southwestern Greenland and Iceland eastward into the northern British Isles, continental Europe, and broad reaches of northern and central Asia, all the way to the Pacific coast (where it overlaps with the Steller’s sea eagle). Wintering grounds extend down into southern Europe and South Asia.

From the icy reaches, behold the magnificent Steller’s Sea Eagle, one of three majestic sea eagle species that brave the subarctic and arctic climates. Their resilience is truly inspiring!

(2) The White-tailed Eagle & its Relatives Rank Among the Biggest Eagles in the World

White-tailed eagles are huge birds, commonly weighing 10 to 15 pounds and boasting a wingspan of up to seven or eight feet. It’s generally a little bit more massive than its near cousin the bald eagle, though Alaskan bald eagles definitely rival white-tailed eagles in size. The Steller’s sea eagle, meanwhile, is larger than both, with females weighing up to 20 pounds, and wingspans that may exceed eight feet.

These big—even, especially in the case of the Steller’s, giant—sea eagles put them up near the top of the eagle size spectrum, other heavyweight species including the harpy eagle and Philippine eagle and, to a lesser extent, the golden eagle, wedge-tailed eagle, Verreaux’s eagle, and martial eagle. The Steller’s sea eagle may be the heaviest eagle in the world, at least on average, and probably boasts the most massive bill. (In terms of birds of prey as a whole, these big sea eagles are outsized by a few Old World vultures, namely the cinereous or black vulture, the griffon vulture, and the Himalayan vulture, as well as the two condor species of the New World, the California and Andean.)

Given their huge geographic range, it’s not surprising that white-tailed eagles show quite a lot of variation in size, with larger-bodied eagles generally found farther north. Some evidence suggests the biggest white-tailed eagles of all call Greenland home.

Witness the majestic power of the white-tailed eagle, one of the world’s largest eagles, as it effortlessly snatches its prey from the sea.

(3) Fish & Birds Constitute Their Most Important Prey & Help Dictate Sea Eagle Habitat

As in many of the sea eagles, fish is a core component to the white-tailed sea eagle diet in most areas, with both marine and freshwater fish landing on the menu. Common fare in this category includes northern pike, carp, Arctic char, and pollock. Waterbirds, from waterfowl and seabirds to wading birds, often vie with fish as the most important prey, although upland birds such as grouse are also targeted. The significance of both marine and freshwater fish and fowl to the white-tailed eagle’s diet—plus the bird’s main hunting method of perching and scanning—helps explain its preferred habitat, typically situated along seacoasts, lakeshores, and marsh- and boglands. Cliffs and large trees with ready access to such open waterscapes make prime nesting sites for this big raptor.

White-tailed eagles do extend their culinary repertoire beyond piscivorous and avian fare: They’ll hunt various mammals as well, such as hares, rabbits, and rodents, and may occasionally take newborn ungulates, such as reindeer calves and roe-deer fawns. That said, a study on white-tailed eagle diet north of the Arctic Circle in Lapland, where expanding eagle populations raised concerns about threats to traditional reindeer husbandry there, found that calves were but a small minority of the eagle’s diet, and it wasn’t clear whether that intake came from scavenging or actual active hunting.

And, indeed, carrion is another mainstay of the white-tailed eagle’s nutrition, as it is for most sea eagles and many birds of prey.

With a firm grip on its catch, this White-tailed Eagle perfectly illustrates why fish are vital to their diet and how abundant prey dictates their chosen habitats. Truly a master angler of the skies!

(4) Glacial Refugia & the Ability to Disperse Long Distances Helped Shape the White-tailed Eagle’s Range

As with many high-latitude organisms, the expansion and contraction of continental ice sheets as well as alpine glaciers during the Pleistocene likely played a profound role on the biogeography of the white-tailed eagle. A 2007 study that identified two major genetic clades within the species suggested western and eastern refugia—ice-free areas offering amenable habitat, climate, and food sources—may have sheltered the eagle during glacial periods, possibly along the Atlantic coast of western Europe and in the Caspian and Black Sea basins, respectively. Expansion (or re-expansion) of the white-tailed eagle into high latitudes appeared to follow quickly after glaciers retreated, probably facilitated by the impressive long-distance dispersal young eagles are capable of.

The same research indicated the white-tailed eagle probably colonized Iceland and Greenland—the most farflung corners of its primarily Eurasian range—from northern or western Europe, with the Faroe Islands being a possible stepping-stone.

Soaring against a breathtaking sunset, the White-tailed Eagle exemplifies the incredible ability of these birds to traverse vast distances, a key factor in shaping their expansive range across continents.

(5) Sea Eagles Construct Some of the Largest of All Bird Nests

As befits their generally hefty size, sea eagles usually build quite big—sometimes downright monstrously big—nests from good-sized branches and twigs. A bald-eagle nest from the vicinity of St. Petersburg, Florida, measured in 1963, ranks as perhaps the largest documented tree nest of any animal: It spanned 9 feet 6 inches (2.9 meters) wide and 20 feet (6 meters) deep, and was estimated to weigh better than 4,409 pounds (i.e., more than two tons). Even more average-sized bald-eagle nests are, considering the full avian panoply, rather supersized: often four to seven feet across and two to four feet tall.

White-tailed eagles also build huge nests, and, like the bald eagle, tend to place them at lofty perches up large trees (including snags) or on cliff faces and other rock outcrops.

his impressive nest, home to a young White-tailed Eagle, showcases the incredible size and robust construction of sea eagle nests—among the largest in the bird kingdom!

Where to See Sea Eagles in the Arctic

Among potential areas to clap eyes on the regal white-tailed eagle up in the Arctic and near-Arctic on a cruise include Svalbard, Iceland, and Greenland, particularly southwestern Greenland. (A good way to be clued into the presence of an eagle is to watch rafts or colonies of seabirds, which may erupt into flight when this long-winged, heavy-taloned hunter comes on the scene—for good reason!)