What is a Golden Eagle? An updated explanation of its characteristics, ecology, and habitat.

What kind of bird is a golden eagle? We will explain its characteristics, ecology, and habitat. The golden eagle is a very large bird that is also a predator. Due to its large body, it can expand its wings to an astonishing size. A summary of the characteristics and ecology of large birds.

What is a golden eagle? About basic status

The golden eagle is a bird classified in the order Accipitridae and the genus Accipitridae. The scientific name is Aquila chrysaetos, and the kanji is dog eagle. The body length is 75-95cm and the weight is 3-5kg. A list of basic information is below. Currently, eagles can be seen distributed all over the world and in Japan in the northern hemisphere. It is very large when it spreads its wings.

Japanese（和名）	イヌワシ
English（英名）	Golden eagle
scientific name(学名)	Aquila chrysaetos
classification（分類）	Ave、Accipitriformes、 Accipitridae、Aquila 鳥綱、タカ目、タカ科、イヌワシ属
IUCN Status(保全状況)	LEAST CONCERN
Length（体長）	75 – 95cm
Weight（体重）	3 – 5kg

What are the roots and origins of the Golden Eagle?

The Golden Eagle (Aquila chrysaetos) is a large bird of prey. Tracing its origins reveals an evolutionary history spanning tens of millions of years leading up to the bird we see today.

Ancestors: Birds of prey from tens of millions of years ago

Taxonomically, eagles—including the Golden Eagle—belong to the family Accipitridae. The ancestors of modern eagles and hawks were carnivorous birds that evolved during the era when mammals flourished following the extinction of the dinosaurs (approximately 66 million years ago or later).

Ancient relatives of the genus Aquila (the true eagles), to which the Golden Eagle belongs, are believed to have existed by the late Miocene epoch (roughly 23 to 5.3 million years ago); the fossil record identifies “true Aquila” eagles dating back about 12 million years.

Evolutionary lineage

The general lineage is as follows:

Birds of the dinosaur era
↓
Primitive birds of prey
(Over 50 million years ago)
↓
Ancestors of the Accipitridae family
(30–40 million years ago)
↓
Large eagles (Aquilinae)
↓
Genus Aquila
(Approx. 12 million years ago)
↓
Golden Eagle
Aquila chrysaetos

Where did they originate?

The exact “place of origin” has not yet been definitively determined.

However, members of the Golden Eagle group are currently widely distributed across:

Europe

North Africa

The Middle East

Central Asia

Siberia

Japan

North America

Genetic studies indicate a history of the population splitting into multiple refugia during the Ice Age and subsequently expanding again. Specifically, a divergence between Asian and Mediterranean lineages has been confirmed.

Why did they become the “Kings of the Sky”?

The characteristics the golden eagle has acquired through evolution include:

a wingspan of over two meters;

powerful gripping strength in its feet;

sharp talons;

vision capable of spotting prey from high altitudes;

and the ability to glide through mountainous terrain.

Its eagle ancestors evolved into aerial predators capable of hunting large animals, and the golden eagle specifically developed the ability to target large mammals—such as rabbits, foxes, and small deer.

About classification

The following subspecies of golden eagles exist:

• Aquila chrysaetos chrysaetos
• Aquila chrysaetos daphanea
• Aquila chrysaetos himeyeri 
• Aquila chrysaetos japonica
• Aquila chrysaetos kamtschatica

Systematic classification

階級	分類
界	動物界（Animalia）
門	脊索動物門（Chordata）
綱	鳥綱（Aves）
目	タカ目（Accipitriformes）
科	タカ科（Accipitridae）
属	ワシ属（Aquila）
種	Aquila chrysaetos

About habitat

Golden eagles are distributed over a fairly wide area, including Eurasia, Africa, North America, Japan (Honshu, Shikoku, Kyushu, etc.), China, and Mexico.

1. Global Habitat

Golden eagles have a very wide distribution, preferring mountainous and open areas throughout the Northern Hemisphere.

Europe

Scotland, northern Spain, Norway, and the Alps

Found in open areas such as mountains, moors, and grasslands rather than forests.

Asia

Central Asia (Mongolia, Kazakhstan)

Siberia, the Himalayas, and the Tibetan Plateau

North America

Canada, Alaska, and the Rocky Mountains

Live in vast grasslands and mountainous areas.

Characteristics:

Prefers high-altitude mountainous areas and valleys.

Prefers open terrain with better visibility and easier hunting than forests.

Avoids snowy and extremely humid areas.

2. Habitat in Japan

Distribution: Mainly Hokkaido

Environment: Mountainous areas, valleys, vast forests, and grasslands

Estimated population: Rare in Japan, with a breeding population of approximately 100-200 birds (Ministry of the Environment Red List: Endangered).

Characteristics:

Some individuals migrate to lowlands and plains in winter.

Breeds on high-altitude cliffs and in trees.

3. Habitat Requirements

Open spaces suitable for hunting (grasslands, hills, valleys)

Trees and cliffs suitable for building large nests

Areas rich in mammals and birds to feed on

feature is? What kind of creature is it?

The golden eagle is black or dark brown, and the feathers on the back of its head are shiny yellow. The feathers covering the base of the tail feathers are light brown. Young birds have a light brown vertical stripe running from the back of the head to the back of the neck. Their main habitat is forests and grasslands, where they are constantly searching for prey. When it spots prey from above, it purses its wings and swoops down to grab it, so the prey is eaten before it is noticed. They live in pairs in the mountains, so they are often observed.

1. Physical Characteristics

Body Size:

Total Length: 75-90 cm

Wingspan: 1.8-2.3 m (Adult birds have very large wingspans, making for impressive flight)

Weight: 3-6.5 kg

Feather Color:

Overall color is dark brown

Golden feathers on the head and back of the neck shine in the sunlight → the origin of the name “Golden Eagle”

Tail feathers are dark brown with slightly lighter tips

Beak and Claws:

Sharp, curved beak for tearing prey apart

Powerful claws (talons) for capturing prey

Eyes:

Yellow eyes with excellent eyesight

Can spot small animals even from high in the air

2. Behavior and Ecology

Hunting:

Mainly feeds on terrestrial mammals (rabbits, squirrels, guinea pigs, etc.) and birds.

Specializes in aerial hunting, swooping down from high altitudes to catch prey.

Typically, they act alone or in pairs.

Nesting:

Builds large nests (1-2 m high, 2-3 m wide) in trees or on cliffs.

Sometimes reuses the same nest for many years.

Reproduction:

Gives birth to 1-3 chicks per breeding.

Both parents take turns raising the chicks.

3. Personality and Characteristics

Intelligence: Highly intelligent and strategic in hunting and nesting.

Vigilance: Highly alert and alert to humans and predators.

Flight: Highly gliding ability, allowing them to fly long distances using the wind.

Sociality: Primarily solitary, but often lives in pairs.

What is the ecology like?

The golden eagle’s diet consists of mammals such as hares, birds of prey, reptiles such as snakes, and animal carcasses. The reproductive form is oviparous. They lay eggs by building nests in trees. Because nesting sites are limited, they often use the same nest every year, and the incubation period is about two months. The lifespan is said to be 20 to 25 years.

1. Behavior and Range

Diurnal: Hunts and travels during the day.

Solo or Pair Life: Low sociality, generally solitary, but cooperates with other eagles during breeding season.

Territorial: Has a large territory during breeding season and avoids intrusion by other golden eagles.

Flight Ability:

Excellent gliding ability.

Uses thermals to travel long distances and conserve energy.

Hunts by diving to catch prey.

2. Diet (What it eats)

Main diet: Medium-sized mammals.

Rabbits, squirrels, guinea pigs, baby antelopes, etc.

Other: Birds (ducks, geese, crows, etc.)

Preying Method:

Dives from high altitudes to catch prey.

Finds small animals on the ground and pounces.

Captures with powerful claws, then tears them apart with their beaks and eats them.

3. Breeding and Nesting

Nesting:

Builds large nests in trees or on cliffs.

May use the same nest for many years.

Breeding Season: Spring to early summer (varies by region)

Number of eggs: 1-3

Brooding:

Both parents cooperate to raise the chicks.

Chicks spend about 1-2 months with their parents in the nest before undergoing flight training and becoming independent.

4. Movement and Distribution

Seasonal Migration:

Northern individuals sometimes migrate to lowlands and plains in winter.

In Hokkaido, Japan, some individuals descend to relatively lowlands in winter.

Habitat:

Mountainous regions, open grasslands, and valleys.

Prefers open areas with better visibility than forests and better hunting conditions.

About Molting

Molting in the golden eagle (Aquila chrysaetos) is the biological process of shedding old feathers and growing new ones. It is a crucial periodic change for the eagle, essential for maintaining its flight and hunting capabilities.

When Golden Eagles Molt

Adult golden eagles primarily molt

from spring to autumn (roughly April through October).

This timing allows them to renew their plumage while expending energy during the period spanning from the breeding season to the chick-rearing phase, following the harsh winter.

However, because losing too many feathers at once would render them unable to fly, raptors replace their feathers gradually over time.

The Molting Process

Feathers are replaced in the following sequence:

① Old feathers weaken

Feather structures deteriorate due to:

Ultraviolet (UV) rays

Friction

Rain and snow

Stress from flight

↓

② Feather bases loosen

The body begins producing new feathers and pushes out the old ones.

↓

③ New feathers (pin feathers) grow

Initially, they emerge as “pin feathers” (or blood quills) containing a blood supply; as they grow, they harden into mature feathers.

↓

④ Fully formed flight feathers

Once the new flight feathers are fully developed, flight performance is restored.

Wing feathers do not all shed at once

Large raptors like the golden eagle replace critical feathers sequentially.

Key feathers:

Primary flight feathers

Located at the wingtips

Crucial for high-speed flight and sharp turns

Secondary flight feathers

Located on the inner part of the wing

Related to gliding ability

Tail feathers

Crucial for changing direction and braking

To ensure they can still hunt while molting, they replace feathers gradually while maintaining balance between the left and right wings.

Molting from juvenile to adult

Golden eagles undergo multiple changes in plumage color as they mature. 0 years old (juvenile)

Overall dark brown-black coloration

White patches on the wings

Prominent white areas on the tail

↓

Ages 1–5

Undergoes annual molting

White patches decrease

Head turns golden-yellow

Body coloration gradually resembles that of an adult

↓

Approx. ages 5–7

Attains full adult plumage

Consequently, its age can be estimated in the wild by observing its plumage patterns.

About Their Calls

Contrary to the impression of being the “King of the Skies” suggested by their appearance, the Golden Eagle (Aquila chrysaetos) produces surprisingly high-pitched, thin-sounding calls. While they are a relatively vocal species among large birds of prey, they are generally very quiet birds.

Typical Calls

Golden Eagle calls are generally described as follows:

“Pee-pee”

High, clear tone

Short, repeated sounds

Used during flight or to communicate with others

“Kee-kee”

Used when alert or wary

Reaction to intruders in their territory

“Kwit-kwit”

Communication between mates

Calls between parent and offspring

These are sharp, whistle-like sounds characteristic of birds of prey—surprising given their large bodies.

Why don’t they have low voices despite their large size?

While large animals like lions and bears produce low-pitched sounds, the situation is different for birds.

A bird’s voice is determined by:

Body size

Trachea length

Structure of the vocal organ (syrinx)

Although the Golden Eagle is a large bird—measuring 80–90 cm in length with a wingspan exceeding 2 meters—its vocal organ is simple for a bird of prey, producing high-pitched calls that carry over long distances.

Situations Where They Call

① Communication between mates

Golden Eagles are monogamous and maintain the same territory for long periods.

When flying apart,

they call back and forth

to signal, “I am here.”

② Territorial defense

When other Golden Eagles or large raptors intrude,

they drive them away using

steep dives,

wing-spreading displays (intimidation),

and vocalizations.

Territorial instincts are particularly strong during the breeding season.

③ Demanding calls from young birds

Chicks in the nest make calls to their parents

to beg for food

or to summon them.

Young birds call more frequently than adults, becoming particularly active when a parent approaches.

Seasonal Activities

The seasonal activities of the Golden Eagle (Aquila chrysaetos) vary significantly depending on breeding, hunting, molting, and territory maintenance. Golden Eagles in Japan (subspecies Aquila chrysaetos japonica) possess a life cycle specifically adapted to the seasonal changes of their mountainous environment.

Spring (March–May)

Season of Breeding Onset and Territorial Defense

Spring is the most critical time of year for Golden Eagles.

Key Activities

Pair flights (display flights)

Territory verification

Nest repair

Egg-laying and incubation

Courtship flights (displays)

In early spring, they perform “undulating flights” characterized by:

Soaring to high altitudes

Diving steeply

Rolling their wings

Chasing one another

These behaviors serve to:

Reaffirm the pair bond

Assert territorial claims against other individuals

Prepare for breeding

Egg-laying

In Japan, egg-laying generally occurs:

Between February and April

Typically, 1 or 2 eggs are laid, though in most cases, only one chick is successfully raised.

Summer (June–August)

Season of Chick-rearing and Peak Demand for Hunting Skills

Summer is an extremely busy time for the parent birds.

Key Activities

Feeding the chicks

Frequent hunting

Guarding the area around the nest

Onset of molting

Parental hunting

Prey includes:

Mountain hares

Copper pheasants

Snakes

Pheasant species

Small mammals

As the chicks grow, their food requirements increase, leading the parents to go hunting multiple times a day.

Growth of the young

In the latter half of summer, the young begin:

Practicing wing-flapping

Flying around the nest

Hunting training

Autumn (September–November)

Season of Independence, Molting, and Territorial Adjustment

Autumn marks a major transitional period for the young birds.

Young birds

They fledge (leave the nest) at approximately 3 to 4 months of age, after which they continue to learn hunting skills from their parents for a time. What they learn:

How to locate prey

Timing for a dive

Using the wind

Avoiding danger

After a few months, they leave their parents’ territory.

Adults

Autumn is the season of molting.

Feathers replaced:

Flight feathers (wing feathers)

Tail feathers

Body feathers

As they grow new feathers, they tend to prioritize flight efficiency over hunting.

Winter (December–February)

A season for survival and maintaining territory

Winter is a crucial period for preparing for the breeding season.

Key activities:

Patrolling the territory

Pair bonding behaviors

Searching for prey

Preparing for courtship

With prey becoming scarce in the snowy mountains, golden eagles rely heavily on their keen eyesight.

From high altitudes, they scan for:

Movement on the snow

Small animals among the rocks

Open slopes

Flight Speed

The flight speed of the golden eagle (Aquila chrysaetos) varies significantly depending on the mode of flight. As a “hunter of the skies,” it prioritizes efficiency during routine gliding but can rapidly increase its speed when hunting.

Normal Flight (Level Flight)

Approximately 45–60 km/h

This is the speed at which golden eagles typically patrol their territories or travel from place to place.

Characteristics:

Slow wingbeats using large wings

Gliding by utilizing updrafts

Capable of sustained flight for long periods

As large birds with a wingspan exceeding 2 meters, they excel at energy-efficient flight that harnesses the wind, rather than the rapid wing-flapping seen in smaller birds.

Gliding Speed

Approximately 50–80 km/h

This is the golden eagle’s most proficient mode of flight.

In mountainous terrain, they maintain altitude with minimal flapping by utilizing:

Slope updrafts

Valley winds

Warm thermal updrafts

This capability allows them to search for prey from the air for extended periods.

Diving Speed ​​During Hunting

Top speed: Estimated to reach approximately 240–320 km/h

When hunting, upon spotting prey from above, the eagle folds its wings and enters a steep dive.

During this maneuver, it achieves extremely high speeds through:

Acceleration due to gravity

Changes in wing shape

Control of air resistance

However, it is not a specialist in high-speed diving to the same extent as the peregrine falcon—known as the world’s fastest bird (capable of dives exceeding 300 km/h, with records surpassing 400 km/h).

The golden eagle is a type of predator that relies on:

A large body, powerful legs, and precise striking ability

…rather than sheer top speed.

About Golden Eagle Chicks

This article provides a detailed summary of the ecology and developmental process of golden eagle chicks.

1. Eggs and Hatching

Egg-laying Season: Spring to Early Summer (April to May in Japan)

Egg Number: 1-3

Egg Characteristics:

White to Light Cream

May have Brown Spots

Hatching Time: Approximately 40-45 Days

2. Chick Development

Immediately After Hatching:

Small body, thin down

Eyes are half-closed, and parents must keep them warm and protected

2-3 Weeks:

Down feathers turn to feathers, and body size increases rapidly

Not yet able to fly, but still fed by parents

1.5-2 Months:

Flight Training Begins

Practices gliding and short-distance flight under the supervision of parents

Independence:

Fledges approximately 2-3 months after hatching

Parents feed the chicks until fully capable of hunting

3. Chick Characteristics

Plumage Color: Lighter brown than adults

Eyes: Grayish, not yellow

Body Size: As they grow, they gradually grow larger, and their wings and tail feathers develop.

Personality: Curious but not yet cautious, they are vulnerable outside the nest.

4. Relationship with Parents

Protection: Parents protect their chicks from predators.

Feeding: Parents feed their chicks with prey they have hunted.

Training: Teaching hunting and flying skills.

Is the golden eagle an endangered species?

The golden eagle is not an endangered species. Instead, it is listed in the Washington Convention, so it is restricted in international trade. As eagles and black-tailed hawks decline, their populations become widely protected. Nature conservation research and activities are becoming more active.

1. Global Conservation Status

IUCN Red List (International Union for Conservation of Nature)

Classification: Least Concern (LC) → Low risk of extinction globally

Reason: Wide distribution, large and stable population worldwide

However, populations may be declining in some areas

2. Conservation Status in Japan

Ministry of the Environment Red List (Japan)

Classification: Endangered (EN)

Reason:

Distribution limited to Hokkaido

Habitat loss due to deforestation and human activity

Threats such as reduced prey and traffic accidents

Protection Measures:

Protection of breeding sites

Population surveys and habitat management

Restrictions on human interference (such as restricting development and forestry near nests)

3. Population in Japan

Breeding population in Hokkaido: Approximately 100-200 birds

Distribution within Japan is extremely limited and highly rare

Can you keep a golden eagle as a pet?

Can you keep a golden eagle as a pet? It is not impossible to keep one, but there are many cases where permission is required. This is because they sometimes attack people and livestock, and they prey on them. It’s not easy at all, so I don’t recommend it to the general public. We recommend viewing it through information about events such as zoos.

1. Legal Restrictions

In Japan, birds of prey require special permission.

Golden eagles are protected under the Wild Bird and Animal Protection Act.

Capturing or keeping them without permission is illegal.

Keeping them is permitted only with permission from the prefectural governor for special purposes (research, education, breeding facilities, etc.).

2. Ecological Reasons

Large and have a strong hunting instinct.

Weight: 3-6 kg, wingspan: approximately 2 m.

Captures prey with sharp talons and beaks.

Dangerous and uncontrollable in a home environment.

Requires a large territory.

In the wild, they fly over tens of square kilometers.

Health and stress management are difficult in cages or indoors.

3. Diet and Environmental Issues

Diet: Mainly wild animals (rabbits, birds, etc.).

Pet food tends to be nutritionally deficient.

Environment: Requires a high nest and ample gliding space.

Indoor breeding or a small garden is not possible.