Emperor Penguin


“Emperor penguins” are often associated with the image of penguins because they have become the main characters of documentary films and have recently appeared as a cute character named “Koupen-chan”.
So, what is the most important thing about Emperor penguins? Let’s explore their secret!



~ Basic information. ~

Aves-Sphenisciformes-Spheniscidae-King penguin genus.



■Changes in body weight.

Male: 36.7kg Female: 28.4kg.(Breeding time)

Male: 24.7kg Female: 32kg.(The period from laying eggs to hatching)

■Flipper (wing) length.

Male: 36.8cm Female: 35.5cm.

■Beak length.

Male: 8.2cm Female: 8.1cm.

■Estimated number of individuals.(FY2017)

590,000 birds.

“Emperor penguins” are also known as “Koutei penguins” or “皇帝 penguins” in Japanese, but for the sake of consistency, I will refer to them as “Emperor penguins” throughout this page.

Emperor penguins are said to be the largest of all penguin species. They have black feathers on their head and throat, with yellowish coloring on their ears and upper chest. Their belly is white, and their back is covered with black feathers. Their legs are also black, and the upper part of their beak is black while the lower part is pink or orange.

It is difficult to distinguish between males and females because they look exactly the same. However, males are generally larger than females, and their maximum body length of about 130 cm is almost the same height as an 8-9 year old child.


Emperor penguins breed from March to April. First, males land on the Antarctic continent or coastal islands, followed by females 2-3 weeks later. This is because they need to eat as much food as possible before laying eggs. After landing, they move to the inland ice fields about 100-200 km away from the coast as much as possible. This is to protect themselves from predators and minimize the impact of strong winds.


After that, they form a group called a “rookery” and mate with each other if they like each other. The bond between couples is relatively weak, and it can be said that it is also a characteristic that they do not make a fixed nest. Females lay only one large egg between March and June, and after laying eggs, they go to the sea to look for food. Therefore, only males carry eggs on their feet.

While other penguins take turns between males and females, it is unique to Emperor penguins that one male continues to warm the egg alone. The incubation period is said to be about two months, and after this period, a chick is born safely. For about 40-50 days after birth, the parent bird wraps it in its stomach and feeds it in turns. When it grows up to some extent, the chick is placed in a group called a “creche”. During this period too, parent birds go to sea to look for food and continue to feed them.


After that, they grow up to about half the weight of their parent birds in about 6 months after birth and leave the nest around December-January. The body of the chick covered with fluffy cotton gradually changes into an adult-like appearance. It can also be said that Emperor penguins have a longer fledgling period than other penguins.




Emperor Penguin’s Q&A.

What is the origin of the emperor penguin name?

Surprisingly, the name of the Emperor penguin is related to the King penguin. In the early 19th century, when no one could go to Antarctica yet, the King penguin was considered the largest penguin in the world. As time went by, in the mid-19th century, humans became able to go to Antarctica, and explorers at that time discovered a bird that closely resembled the King penguin.

At first, it was thought to be a member of the King penguin species, but further investigation revealed that it was a different species. Due to its larger size compared to the King penguin, it was named after an Emperor which is higher in rank than a King, and thus it was named Emperor penguin.


Why do emperor penguins live there?

“Emperor penguins” mainly breed on the Antarctic continent, and they choose islands along the coast and offshore between 66°S and 78°S. In addition, Emperor penguins have been sighted in other locations such as Tierra del Fuego, the Falkland Islands, South Georgia Island, South Sandwich Islands, Kerguelen Island, Heard Island, New Zealand, and South Africa.

Although it is possible that they drifted there by chance, it is said that under the ice of the coast and islands of Antarctica, there are large numbers of Antarctic krill and fish, which makes it easy for them to find food if they live there.


What do emperor penguins eat?

Emperor penguins primarily feed on fish such as squid, octopus, Antarctic silverfish, and crustaceans like Antarctic krill. In the case of chicks, they receive regurgitated fish from their parents. It is said that chicks can eat as much as 3-4 kg at once.


Why are emperor penguins shaking their heads?

In conclusion, I will introduce the reasons separately for adult and chick Emperor penguins.

■For adult birds.

They have an organ called the salt gland above their eyes, and they shake their heads to excrete excess salt from their bodies.

■For chicks.

It is said to be a way of begging for food from the parent bird.


Why do emperor penguins lay eggs in frigid winters?

Other penguin species often breed from spring to early summer, which is usually between November and January in Antarctica. However, Emperor penguins lay eggs and raise chicks from March to June. This is the season when autumn is approaching winter in Antarctica. But why do they choose such a difficult time?

This is related to the Emperor penguin’s “large body” and its main food, “Antarctic krill”.

The first reason is that, as we mentioned in the basic information, it takes six months for Emperor penguin chicks to become independent after birth. Since the summer in Antarctica is very short, if they lay eggs in spring and early summer like small penguins, the chicks will face another winter before they become independent. By laying eggs in the extreme cold of winter, chicks can become independent before facing a second winter.

The second reason is that Antarctic krill increases in number from spring to early summer (November to January). In other words, this season is when Emperor penguins have more food to eat. Large Emperor penguins eat a lot of food, and this also applies to fledgling chicks.

To ensure that fledgling chicks eat enough food, it is necessary to overlap the period when food increases with the period when chicks leave the nest. Therefore, if they do not lay eggs in winter and work backwards, they will not be able to catch up with the period when food becomes abundant.

In addition, there are almost no natural enemies in Antarctica during winter. Therefore, winter breeding also has advantages in that sense.


Is it true that Emperor Penguins are the harshest parenting in the world?

It’s true. Now, let’s take a look at what kind of parenting you will do.

■The ordeal begins right after the female lays eggs!

As I mentioned in the basic information, it is the male’s responsibility to incubate the eggs received from the female. However, if he is not careful and places the eggs on his feet, they may break, or if the eggs touch the ice for an extended period, they may freeze.

■In the midst of a raging blizzard, the male risks his life to warm the eggs!

Once the male safely receives the eggs from the female, he will continue to incubate them for about two months without eating anything. However, in reality, even during his journey to the breeding grounds called “rookeries” (colonies), he is in a state of fasting because of the lack of food. This means that he has not eaten anything for more than two months. Furthermore, during this period, Antarctica experiences “blizzards,” which are severe snowstorms. As a result, males who cannot withstand these extreme conditions may die.

To endure these harsh conditions, Emperor penguins form a huddle by gathering together and leaning on each other to keep warm. After surviving this challenging period, chicks are born safely. However, at this time, male penguins have lost approximately 30% of their body weight. For example, if a male weighs 60 kg, he would weigh 40 kg after this period.

■Just wait for the female to return! But when you can’t get food in time…

After laying eggs, females head to the sea to feed themselves and store food for the males and chicks waiting at the rookeries. However, if the female’s arrival is delayed, males may resort to an emergency measure by feeding their chicks with “penguin milk.”

Penguin milk is made by scraping off the mucous membrane of their stomachs and esophagus and contains protein. If we count from the breeding season to this time period, males have fasted for a total of about four months. Despite their tremendous efforts, some males do not have enough energy to survive until the female’s return and die along with their chicks.

■The scalpel is back! But my physical strength is really the limit…

Once females return safely, males head to the sea to eat food. However, it is about 100 km or more to reach the sea. Since males have not eaten anything until this point and have exceeded their physical limits, they may run out of energy before they can eat.

Females lay eggs while males keep them warm. Then they feed their chicks plenty of food and go to sea. They reunite with males who went out to sea and live together as a family. It can be said that it is truly a miracle to connect this process until the end.


Is it true that emperor penguins compete for chicks?

Indeed. This happens when the male dies while incubating the eggs and is unable to hatch them. Alternatively, if the eggs hatch but the chicks die along the way, females who were unable to become mothers for some reason go into a frenzy and try to snatch chicks from other mothers.

However, chicks caught up in this frenzy are often pecked to death. Even if a female successfully steals a chick, she may abandon it during the process of raising it, resulting in the chick’s death. Emperor penguins breed in extremely harsh environments, which makes such incidents more likely to occur.


I want to know more about the personality of the emperor penguin!

Emperor penguins are characterized as “calm and composed birds”. They have an elegant appearance that is truly befitting of their name. Moreover, they exhibit social behavior by forming huddles to protect themselves from the cold during blizzards.

By the way, there are occasional videos showing Emperor penguin fledglings being chased by Adélie penguins. Despite being larger, the Emperor penguin fledglings do not fight back seriously, which may be evidence of their gentle nature.

Is there a place where I can see emperor penguins?

As of November 2021, Emperor penguins are only kept in two places in Japan: Nagoya Port Aquarium in Nagoya City, Aichi Prefecture, and Adventure World in Shirahama Town, Wakayama Prefecture.

For those who want to see Emperor penguins in the wild, there is also the option of participating in an Antarctic cruise. Although the travel cost can be quite high, you can apply through a travel agency. I hope this information helps you.

出典:https://commons.wikimedia.org/wiki/File:Emperor Penguins & Chris Michel (15885637606).jpg

Do emperor penguins have natural enemies?

Emperor penguins have natural predators such as orcas, sharks, and leopard seals. The South Polar Skua bird also targets their chicks. However, the biggest threat to Emperor penguins may be humans.

Currently, the International Union for Conservation of Nature (IUCN) has classified Emperor penguins as “Near Threatened”. The primary cause is the “reduction in food and breeding grounds due to global warming”.

As the ice melts and the area of ice fields decreases due to global warming, the algae that live there also decrease. Consequently, Antarctic krill, which feeds on algae, also decreases in number. Emperor penguins, which feed on Antarctic krill, are affected by this decrease in food. Furthermore, Emperor penguins take time from laying eggs to their chicks becoming independent. If the ice fields continue to shrink, there is a risk that all the ice will melt before the chicks become independent.

In recent years, people have expressed concerns about unexpected phenomena occurring due to global warming. This is an opportunity for us to consider building a better relationship between humans and penguins together.


What is the lifespan of an emperor penguin?

The lifespan of Emperor penguins living in the harsh natural world is up to approximately 20 years.





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