What kind of bird is the White-tailed Eagle? An updated explanation of its characteristics, ecology, and habitat

What kind of bird is a white-tailed eagle? We will explain its characteristics, ecology, and habitat. With a wingspan of 220 cm, it is quite strong among eagles and hawks. White-tailed eagles can be seen not only in Eurasia but also in Denmark and other countries.

What is a white-tailed eagle? About basic status

The white-tailed eagle is a bird classified in the genus White-tailed Eagle, in the order Accipitridae and in the family Accipitridae. Total length is 70-98cm, wingspan 180-240cm. Weight will be 3 – 7 kg. The scientific name is Haliaeetus albicilla, and the kanji is “tailed eagle”. The list of information is as follows.

Japanese（和名）	オジロワシ
English（英名）	White-tailed eagle
scientific name(学名)	Haliaeetus albicilla
classification（分類）	Ave、 Accipitriformes、Accipitridae、Haliaeetus 鳥綱、タカ目、タカ科、オジロワシ属
IUCN Status(保全状況)	LEAST CONCERN
Length（全長）	70 – 98cm
Weight（体重）	3 – 7kg

What are the roots and origins of the White-tailed Eagle?

The White-tailed Eagle (scientific name: Haliaeetus albicilla) is a large sea eagle belonging to the family Accipitridae (hawks and eagles). In Japan, it arrives as a winter visitor, primarily in Hokkaido.

Its evolutionary roots lie in the lineage of eagles that developed as large birds of prey inhabiting waterside environments.

Ancestors: “Ancient Birds of Prey”

The ancestors of eagles and hawks were early birds of prey that appeared approximately 50 million years ago or earlier.

The general evolutionary progression is as follows:

Early birds of prey
(Carnivorous birds of the Paleogene period)
↓
Accipitridae (Hawks and eagles)
↓
Large eagles
↓
Genus Haliaeetus (Sea eagles)
↓
White-tailed Eagle
(Haliaeetus albicilla)

Emergence of the Genus Haliaeetus (Sea Eagles)

The genus Haliaeetus, to which the White-tailed Eagle belongs, is a group of eagles that evolved with the following characteristics:

Catching fish

Utilizing lakes, rivers, and coastlines

Possessing a large body size

Representative species include:

White-tailed Eagle

Bald Eagle (Haliaeetus leucocephalus)

Steller’s Sea Eagle

Solomon Sea Eagle (depending on classification)

Place of Origin of the White-tailed Eagle

The ancestors of the White-tailed Eagle are believed to have evolved primarily in the waterside environments of northern Eurasia.

Current distribution:

Northern Europe

Russia

Siberia

Central Asia

East Asia

Japan (e.g., Hokkaido)

The stage for their evolution was specifically regions rich in:

Large rivers

Lakes

Coastlines

Wetlands

About classification

There are two subspecies of white-tailed eagles.

Haliaeetus albicilla albicilla 

It is found throughout the world, except in Greenland. They mainly fly to Hokkaido from Russia during the winter.

Haliaeetus albicilla groenlandicus

Individuals found only in Greenland correspond to this subspecies.

Taxonomy

• 界 (Kingdom): Animalia（動物界）
• 門 (Phylum): Chordata（脊索動物門）
• 綱 (Class): Aves（鳥綱）
• 目 (Order): Accipitriformes（タカ目）
• 科 (Family): Accipitridae（タカ科）
• 属 (Genus): Haliaeetus（オジロワシ属）
• 種 (Species): Haliaeetus albicilla（オジロワシ）

Note: The White-tailed Eagle is a large eagle that is adapted to coastal and open environments around lakes and ponds, and is distributed widely throughout the Northern Hemisphere.

About habitat

The white-tailed eagle is distributed in Eurasia, Japan, and Denmark.

1. Natural Distribution (Place of Origin)

Northern Europe to Russia

Northern Europe (Norway, Sweden, Finland)

Baltic States, Northwestern Russia

Northern Asia to East Asia

Siberia, Mongolia, Northern China, Korea, Japan (Hokkaido)

A closely related species, the Bald Eagle, exists in North America.

2. Habitat

Live mainly near water, such as lakes, rivers, wetlands, and coasts.

Breed and rest in open forests and treetops on forest fringes.

Often build nests in tall trees or on cliffs.

Prefer areas near water with an abundance of fish and waterfowl.

3. Altitude/Range

Mainly flatlands to low mountains (0-1000 m)

Wide distribution, from coastal areas to inland lakes and ponds.

4. Migration/Migration

Partially migratory

Individuals in Northern Europe and Siberia migrate south in winter

Individuals in Hokkaido, Japan, and East Asia are mostly sedentary

When feeding areas, such as lakes and ponds, freeze over, they migrate to find open water

5. Distinctive Habitat Requirements

As a large eagle, it requires a wide hunting range

It is important for the area to have an abundance of fish and waterfowl, as well as tall trees and cliffs where it can safely rest.

feature is? What kind of creature is it?

White-tailed eagles are members of the eagle and hawk family, and like the Steller’s sea eagle, females are larger than males. The whole body is dark brown, and the head is covered with pale brown or pale yellow feathers. The tail has 12 short feathers, and the tail is slightly wedge-shaped. The color of the tail feathers is white. It migrates throughout Japan as a winter bird. Their habitat is coasts, rivers, lakes, etc.

1. Appearance and Physical Characteristics

Body Size

Body Length: Approximately 70-90 cm

Wingspan: Approximately 1.8-2.4 m

Weight: Approximately 3-6 kg

Body Color

Adult: Brown body with white tail feathers

Young Bird: Brown tail and takes several years to reach adulthood

Beak, Legs, and Claws

Their beaks are yellow and curved, suitable for catching fish and small animals.

They use powerful claws to grasp prey.

2. Behavior and Personality

Personality

Timid and cautious

They usually live alone or in pairs.

Flight Ability

Powerful wings allow them to glide for long periods of time.

They sometimes fly low above the water surface to hunt for fish.

Hunting Behavior

Preys on fish, waterfowl, and small mammals.

They have excellent eyesight for hunting near water.

3. Sociality

They are generally solitary outside of the breeding season.

They may come into contact with other individuals at feeding and resting areas.

What does the ecology look like?

White-tailed eagles are carnivorous, preying on fish, birds, and mammals. They also often eat carcasses. Prey is often captured by swooping down. The reproductive form is oviparous. The female lays two eggs at a time in March-April and incubates them. They reach sexual maturity at 5-6 years of age and have a lifespan of about 20 years.

1. Habitat

Live mainly near water, such as lakes, rivers, wetlands, and coastlines.

Rest and nest in open forests or tall trees.

Select areas with abundant fish and waterfowl.

2. Diet

Carnivorous (primarily fish-eating).

Preys primarily on fish.

Also eats waterfowl, small mammals, and carrion.

Hunting Method

Glides near the water’s surface and then dives down to catch fish.

Their claws are very powerful, and they sometimes fly back to their prey.

3. Social Behavior

Primarily lives alone or in pairs.

During the breeding season, they defend their territory as a pair.

Even during the non-breeding season, they may encounter other individuals at feeding areas.

4. Breeding Behavior

Nesting: They build large nests (approximately 1.5-2 cm in diameter) on top of tall trees or cliffs. m)

Breeding Season: Winter to Spring (Varies by Region)

Number of Eggs: Usually 1-3

Parent Roles

Both parents take turns incubating the eggs and feeding the chicks

Growing is slow, and it takes several months for them to fledge

5. Migration/Migration

Partially Migratory

Individuals in Northern Europe and Siberia migrate south in winter

Sedentary

Many individuals are sedentary in Hokkaido, Japan, and warmer regions of Western Europe

Local migration in frozen lakes and ponds, seeking open water

Are there any natural enemies?

White-tailed eagles have no natural enemies. It is the highest bird in the sky.

About Molting

Molting in the White-tailed Eagle (Haliaeetus albicilla) is a vital physiological process in which feathers are gradually replaced as the bird grows and ages, and in response to seasonal changes.

Basics of Molting

Bird feathers play crucial roles in:

Flight

Body temperature maintenance

Waterproofing

Hunting ability

Consequently, old feathers are replaced periodically.

White-tailed eagles do not lose all their feathers at once;

instead, they undergo “sequential molting,”

where feathers are shed and replaced gradually and in a specific order.

As a result, there is essentially no period during which they are unable to fly.

Molting Season

Spring to Summer (Primary Molting Period)

For many individuals,

molting becomes most active

between May and September.

Reasons:

Breeding activity subsides

Food availability becomes relatively stable

Feathers are renewed before the harsh winter environment

Wing Molting

Wing feathers (remiges) are critically important.

Feathers replaced include:

Primaries (wingtips)

Secondaries (inner wing)

Tail feathers

etc.

Characteristics:

Replaced gradually and symmetrically (left and right sides)

Flight ability is maintained

Complete renewal takes several years

About Their Calls

Despite their massive size, White-tailed Eagles (Haliaeetus albicilla) do not produce the sort of low, ferocious roar one might imagine. Instead, they are birds of prey that emit a series of high-pitched, piercing calls.

Typical Calls

Their calls can be described as sharp sounds resembling a whistle, such as:

“Kee-kee-kee”
“Kwi-kwi-kwi”
“Pii-yo, pii-yo”

Characteristics:

High-pitched

Resonant/Carrying

Repeated/Continuous

Audible from a great distance

Although they are large eagles, the quality of their voice is surprisingly delicate.

Breeding Season Calls

Spring (mainly around February to May) is the time when their calls are most frequently heard.

Communication between mates

Pairs engage in behaviors such as:

Alternating calls between male and female

Calling while flying above the nest

Asserting territorial boundaries

Their calls convey information such as:

“This is our territory”

“My mate is nearby”

“The nest is safe”

Chick Calls

The calls of the chicks change as they grow.

Young chicks

Emit soft “pee-pee” sounds

Call to beg for food

Older chicks

Voices become louder

Make more demands of the parent birds

When a parent approaches,

They call out to signal, “Bring me food.”

Seasonal Activities

The White-tailed Eagle (Haliaeetus albicilla) is a large bird of prey whose habitat, hunting methods, and breeding behaviors change significantly with the seasons.

Spring (March–May)

Season for Breeding and Territory Defense

Spring is the most critical time of year for White-tailed Eagles.

Key Activities

Defending territory as a pair

Repairing the nest

Mating

Egg-laying

Beginning to raise chicks

Nest Building

White-tailed Eagles build massive nests.

Locations:

Large trees near the coast

Forests along rivers

Clifftops

Areas around lakes and marshes

Nests are often reused year after year; as new branches are added, they can grow to:

Over 1–2 meters in diameter

Weigh several hundred kilograms

Hunting

In spring, parent birds:

Catch fish, waterfowl, and small mammals

Carry the prey back to the chicks

Summer (June–August)

Raising Chicks and Fledgling Growth

Summer is the peak period for breeding activities.

Chick Growth

After hatching, chicks:

Initially stay in the nest

Gradually strengthen their wings

Fledge (leave the nest) after a few months

Parent Bird Behavior

Parents take turns:

Guarding the nest

Bringing food

Protecting chicks from heat and rain

Flight Training

Young birds develop their flying skills by:

Flying around the nest area

Moving from branch to branch

Practicing gliding

Autumn (September–November)

Season for Migration and Winter Preparation

In autumn, northern populations migrate southward.

Migration

From:

Russian Far East

Sakhalin

Kamchatka region

↓

To:

Hokkaido

Sea of ​​Japan coast

Autumn Behavior

They begin to:

Search for areas rich in food

Rest in flocks

Secure winter territories

Winter (December–February)

The Best Season for Observation in Hokkaido

Winter is the time when White-tailed Eagles are most conspicuous in Japan. Key locations:

Hokkaido coast

Rivers

Lakes

Wetlands

Areas near drift ice

Regarding Flight Speed

Unlike high-speed falcons, the White-tailed Eagle (Haliaeetus albicilla) is an eagle specialized for gliding and energy-efficient flight using its massive wings.

Normal Flight Speed

The White-tailed Eagle’s cruising speed is estimated to be:

Approximately 40–50 km/h

Typical situations include:

Moving within its territory

Traveling to feeding grounds

Patrolling over coastlines or rivers

In these scenarios, it flies at this speed.

Gliding Speed

The White-tailed Eagle excels at gliding rather than flapping flight.

By utilizing updrafts, it can fly for extended periods at speeds of:

Approximately 30–60 km/h

Characteristics:

Minimal wing movement

Low energy expenditure

Ability to monitor a wide area

These are the advantages of this flight style.

Diving Speed

Speed ​​increases when targeting prey.

During a dive:

It can reach speeds exceeding 100 km/h

However:

It does not perform the 300 km/h-class diving attacks seen in falcons.

Reason:

The White-tailed Eagle primarily hunts by:

Grabbing fish

Scavenging carcasses

Attacking waterfowl

Consequently, ultra-high-speed dives are unnecessary.

About White-tailed Eagle Chicks

This section provides a detailed overview of White-tailed Eagle (Haliaeetus albicilla) chicks. White-tailed eagles are large birds of prey, and parental cooperation and a safe nest environment are crucial for their development.

1. Birth and Hatching

Number of Eggs: Usually 1-3

Incubation Period: Approximately 35-42 days

Characteristics Immediately After Hatching

Feathers: Soft, pale gray to white down

Beaks and talons are still weak, and they cannot fly

Compared to adults, they are smaller and weaker

2. Life in the Nest

Nest Location

Large nests (approximately 1.5-2 m in diameter) built on tall trees or cliffs

Parent Care

Both parents take turns incubating and feeding the eggs

Hide chicks or defend the nest in times of danger

Diet

Parents feed them primarily fish and small animals caught by mouth

3. Growth Process

Early Stage (Immediately after hatching – 2 weeks)

Feathers are soft and unable to fly

Completely dependent on parents’ temperature control and food

Middle Stage (2 weeks – 2 months)

Feathers grow and their bodies become stronger

Claws and beaks become stronger, and they are able to feed themselves a little

Late Stage (2-3 months)

Feathers approach those of adult birds, enabling them to fly short distances

Begins preparations for fledge

4. Fledge

Time to learn flight: Approximately 2-3 months

After fledge

At first, they fly close to their parents and learn prey techniques

Gradually become independent and begin catching fish and small animals on their own

5. Characteristics and Biology

Chicks’ feathers are paler and softer than those of adults

Under the protection and guidance of their parents, they learn how to forage and fly

The safety of the nest is directly linked to the chicks’ survival

Is the white-tailed eagle an endangered species?

White-tailed eagles are the largest species of eagles and hawks, so they have no natural predators. Therefore, it is not an endangered species. The population is stable. However, it is designated as an endangered species in Japan. Their numbers are drastically decreasing due to the destruction of nesting grounds due to deforestation, land reclamation, and road construction. It is designated as an endangered species. It is also listed in the Washington Convention. It is a wild bird designated as a natural monument by the Ministry of the Environment, and in 1993, it was designated as a domestic rare species of wild fauna and flora under the enforcement of the Species Conservation Act.

1. IUCN Red List Assessment

Classification: Least Concern (LC)

Reason: Widely distributed throughout the Northern Hemisphere, with total populations stable or recovering.

2. History of Endangered Species

Until the mid-20th century: Populations plummeted due to pesticides (DDT), hunting, and environmental destruction.

Recently: Populations have been recovering due to conservation efforts and environmental regulations.

3. Regional Status

Japan (Hokkaido)

A small number of resident individuals remain, and conservation efforts are underway.

Europe and Russia

Populations have recovered and are stable, particularly in Northern Europe.

Siberia and Northern Asia

Large populations with widespread distribution.

Can white-tailed eagles be kept as pets?

Because of the above, it is difficult to keep them as pets. Because it is large, you can take good photos even in nature. In Japan, they winter in the northern part of Japan, so let’s take some photos.

1. Difficulty in Keeping

Body Size

Body Length: Approximately 70-90 cm

Wingspan: Approximately 1.8-2.4 m

Weight: Approximately 3-6 kg

It is almost impossible to find space in the home for them to fly.

High Flying Ability

Capable of long glides and dives, they experience stress in small spaces.

Highly Wild Nature

Very wary and difficult to tame.

2. Personality and Behavior

Can be timid and aggressive.

They have a strong prey instinct and may harm hands or pets.

Adapted to living alone.

They may feel loneliness and stress in captivity.

3. Laws and Protection

In Japan, some areas are designated as natural monuments, requiring special permission to keep them.

Internationally, eagles are subject to the Convention on the Protection of Eagles and Hawks and the Eagle Protection Act.

Keeping or selling them without permission is illegal.

4. Breeding Examples

Most birds are kept in zoos or raptor sanctuaries.

Requirements:

Large outdoor flying space (at least several hundred square meters)

Maintain a raw meat diet, primarily of fish and small animals

Protect nests and chicks during breeding season

Summary
White-tailed eagles are large raptors that are not suitable as pets and should be kept in specialized facilities under natural conditions.