1. Home
  2. Fun Animal Facts
  3. Changeable Hawk-Eagle: 15 Facts You Won’t Believe!

Animals

Kidadl Team

SEPTEMBER 02, 2021

Changeable Hawk-Eagle: 15 Facts You Won’t Believe!

Read more fun changeable hawk-eagle facts here.

The changeable hawk-eagle (Nisaetus cirrhatus), also known as marsh hawk-eagle, crested hawk-eagle, or Indian crested hawk-eagle, is a large bird of prey of the family Accipitridae. This hawk-eagle is in the subfamily Aquilinae with distinct feathers covering the tarsus, which are absent in raptors outside the family. Booted eagle is the common name used for the species of this subfamily. This hawk-eagle was previously placed in the genus Spizaetus. However, research pointed to the group being paraphyletic resulting in the Old World members being placed in genus Nisaetus, separating them from the New World species. The name 'hawk-eagle' means that these birds are agile predators and easily vary their prey selection between mammals, reptiles, vertebrates, and birds like eagles.

The word 'changeable' refers to the changing dark morph to pale morph and vice-versa. These birds are the most abundant and adaptable species. Nisus de Lacepede first named this genus in 1799. The second part of the genu 'aetos' means 'eagle.' There are 10 described species within this genus. The changeable hawk-eagle has a dark-brown upper part and white underpart. There are two separate groups with the changeable hawk-eagle, with hardly visible or without crests and with a crest of four feathers. In some populations, the dark morph exists.

If you enjoyed reading these facts, then make sure to check out some fun crowned eagle and tawny eagle facts on Kidadl.

Changeable Hawk-Eagle Interesting Facts

What type of animal is a changeable hawk-eagle?

The changeable hawk-eagle (Nisaetus cirrhatus) is a large bird of prey of the order Accipitriformes and phylum Chordata. There are five subspecies of this bird, Nisaetus cirrhatus ceylanensis, Nisaetus cirrhatus cirrhatus, Nisaetus cirrhatus andamanensis, Nisaetus cirrhatus limnaeetus, and Nisaetus cirrhatus vanheurni. They have similar adaptations to true hawks. On the accounts of anecdotes, wide-ranging bird census surveys, eye-witnesses, and photogenic evidence conclusions of the dietary biology of this hawk-eagle were drawn.

Flores hawk-eagle (N. floris) appears as monophyletic lineage with Nisaetus cirrhatus andamanensis and Nisaetus cirrhatus vanheurni. However, the placement of the Flores hawk-eagle is unresolved. Different lineages are not stable and are described to be polytomy and from this similar island, taxa derive. Obviously, Nisaetus cirrhatus limnaeetus does not represent the monophyletic lineage. The island taxa that are derived from Nisaetus cirrhatus limnaeetus seems to have been undergone founder effects. In continental populations, genetic diversity is significant. Therefore, Nisaetus cirrhatus limnaeetus (crestless changeable hawk) is considered metapopulation.

What class of animal does a changeable hawk-eagle belong to?

The changeable hawk-eagle (Nisaetus cirrhatus) belongs to the class of Aves of animals.

How many changeable hawk-eagles are there in the world?

The exact number of changeable hawk-eagle (Nisaetus cirrhatus) species in the world is not known. However, the population of this species is a five-figure number or even higher.

Where does a changeable hawk-eagle live?

The changeable hawk-eagle (Nisaetus cirrhatus) is found across Southeast Asia and the Indian subcontinent. This bird inhabits the Himalayan foothills, Sri Lanka, southern Nepal, and Bhutan east to Burma, Myanmar, southern Vietnam, western Laos, peninsular Malaysia, Thailand, and Cambodia. This hawk-eagle's range extends from the peninsular tip in the north of India to Uttar Pradesh, Rajasthan, Odisha, and Bihar. This species can also be found in Sumatra, western and southern Philippines, Boneo, Andamans, and Java.

Nisaetus cirrhatus ceylanensis subspecies are endemic to Sri Lanka, including Travancore. The Nisaetus cirrhatus cirrhatus subspecies are found in peninsular India from Gangetic plain to southwards. Nisaetus cirrhatus andamanensis subspecies are found in the Andaman Islands. Nisaetus cirrhatus vanheurni subspecies are native to Simeulue Island. Nisaetus cirrhatus limnaeetus subspecies can be found near the Himalayan foothills from Nepal and Burma to most parts of Southeast Asia.

What is a changeable hawk-eagle's habitat?

The changeable hawk-eagle (Nisaetus cirrhatus) can be found in timbered watercourses, cultivation with trees, savannah woodland, suburban edge, forest villages, and tea plantations.

Who do changeable hawk-eagles live with?

The changeable hawk-eagle (Nisaetus cirrhatus) lives on their own.

How long does a changeable hawk-eagle live?

The lifespan of the crested hawk-eagle (Nisaetus cirrhatus) is not yet known. However, the goshawk can live up to 11-27 years.

How do they reproduce?

Crested hawk-eagle (Nisaetus cirrhatus) pairs mate for life. The pair then engages in a territorial ritualistic display. Males are usually the ones to engages in these displays but sometimes females or both birds engage in aerial displays. They first shoot up and then nose-dive and if they continue with the display, both birds fly towards each other at lightning speed and complete a loop-the-loop turn in the air. Throughout this display, they might call out loudly. The breeding season in south India is from November to May and in the temperate Himalayan foothills, it is from January to March. The breeding season in Sri Lanka has the same time period as India. However, peak laying dates is from January to February. In the Greater Sunda Islands, a record states that eggs were present after eight months from December to October and peak activity between February and August. The breeding season in these tropical forests is more flexible compared to the cool dry season in the northern ranges.

They build large nests made of sticks and the nests are large compared to the size of these birds. It can also be lined with green leaves. These nests are also more resilient than medium-sized eagle's nests. The nest is placed at 20-164 ft (6-50 m) above ground in a large tree fork or crown. These changeable hawk-eagles lay one egg.  The white egg with a light reddish botch is glossless and coarse. The egg measures up to  1.96-2.1 in (49.9-53.3 mm) in diameter. Only the female incubates the egg for 40 days and the female broods for 25 days after the nestlings are out. Around 35 days, the nestling's body size and feathers grow and brooding gradually decreases. Parents encourage the young one to eat their prey placing the prey on a nearby branch. The eaglet is fully grown by the 52nd day and the eaglet fledges after 60-68 days.

What is their conservation status?

The conservation status of these changeable hawk-eagle birds is Lest Concern. However, other Nisaetus species are depleting with deforestation. The population of these eagles is steady or even increasing. A growth in the population has has been reported in Java, the Indian subcontinent, the Philippines, and Malaysia, and in other parts of Southeast Asia.

Changeable Hawk-Eagle Fun Facts

What do changeable hawk-eagles look like?

Changeable hawk-eagles are slender-bodied large birds and are dimorphic. Adults have dark brown upper part and white underpart. They have a strong bill, a floppy crest of four feathers or no crest, long feathered chest, thinly barred long tail, and short wings. Changeable hawk-eagle 'light morph' adults have pale edges on their dark brown upper bodies. The head and neck are rufous with black-streak and if present, a black crest. The tail is pale brown with a white tip and a black broad band. There is a dark brown to black streak on their pale underside. Subspecies like N. c. limnaeetus have further intermediate and dark morph. The intermediate morph is identical to the pale morph adult species but with heavily gray below, more obscure streaks, and unpatterned belly to crissum.  Dark morph adults are dark chocolate brown to black with varying brown edges which is diminished only by the tail's gray inner half and some gray tail bars.

Juveniles are mostly brown with more white edges on wings and mantle than adults. There are seven thin dark bars on the light brown tail of juveniles with whitish tips.  The head is either dark brown or buff with a white-tipped black crest. The changeable hawk-eagle in flight appears to be a large raptor with a noticeable head, rounded tail, and short round and broad wings but have straighter trailing edges and slender wings. Usually, in-flight, juveniles show more area with white streaks. Nisaetus cirrhatus ceylanensis (crested hawk-eagle) has a longer crest than the nominate species.

The changeable hawk-eagle's habitats overlap with the mountain hawk-eagle species.

How cute are they?

The crestless or crested hawk-eagle is not considered cute.

How do they communicate?

The changeable hawk-eagle call is a high-pitched scream. Their call is described to be 'yeep-yip-yip-yip,' rises 'kwip-kwip-kwee-ah' and 'klee-leeuw'. The call differs in Sri Lanka and India with a sound of 'ki-ki-ki-kee' that begins short, rising in crescendo, and ends in a long scream.

How big is a changeable hawk-eagle?

The changeable hawk-eagle size is 60-72 cm (24-28.3 in). Nisaetus cirrhatus ceylanensis is 22-24 in (55-60cm). Females are larger than males. The harpy eagle is twice as long as these hawk-eagles.

How fast can a changeable hawk-eagle fly?

The flight of this species is agile and fast. However, the flying speed is not known.

How much does a changeable hawk-eagle weigh?

These birds weigh around 2.6-4.2 lb (1.2-1.9 kg).

What are the male and female names of the species?

There is no specific name given to male and female changeable hawk-eagle birds.

What would you call a baby changeable hawk-eagle?

There is no specific name given to the baby changeable hawk-eagle. They are usually referred to as juveniles or nestlings.

What do they eat?

These birds feed on reptiles, amphibians, mammals, and other birds. Their diet includes pheasants, hares, junglefowl, ducks, squirrels, snakes, and other small animals.

Are they dangerous?

These birds placed in the genus Nisaetus are not dangerous to humans.

Would they make a good pet?

No, they would not make a good pet.

Did you know...

The mountain hawk-eagle can sometimes be spotted in a group or a flock.

Why is it called the changeable hawk-eagle?

These species placed in the genus Nisaetus are named this because they are agile predators and easily vary their prey selection between mammals, reptiles, vertebrates, and birds like eagles. This gives them the name 'hawk-eagle'. The term 'changeable' refers to the changing dark morph to pale morph and vice-versa.

What are the changeable hawk-eagle's wings like?

The wingspan of these hawk-eagles is 39-63 in (100-160 cm). The wings are short, broad, slender and they reach one-third to halfway to the tail.

Here at Kidadl, we have carefully created lots of interesting family-friendly animal facts for everyone to discover! For more relatable content, check out these sea eagle facts and white gyrfalcon facts for kids.

You can even occupy yourself at home by coloring on one of our free printable mountain hawk eagle coloring pages.

Subscribe_Hero
Get The Kidadl Newsletter
1,000's of inspirational ideas direct to your inbox for things to do with your kids.

By joining Kidadl you agree to Kidadl’s Terms of Use and Privacy Policy and consent to receiving marketing communications from Kidadl.

EXPLORE KIDADL
In need of more inspiration?