Japanese Red-crowned crane facts
Common Name: Japanese crane or red-crowned crane
Scientific Name: Grus japonensis
Size and Appearance: These particular birds are often confused with oriental storks because of their similarity in plumage. However, they have a distinctly black neck and the top of their heads have a bright red cap. On top of that their beaks are pointed and short compared to the long flat beaks of the oriental stork.
Usually, their size ranges between 150 to 158 cm in height and 100 to 150 cm in length. Their wide wingspan can reach up to 2.5 meters. It is also quite a heavy species of birds whose average ranges between 8 to 10 kg. The heaviest bird recorded is about 15 kg. The females are considerably smaller than males.
Life Span: Impressively, the average life expectancy of a red-crowned crane is about 25 years in the wild. It is also believed that, on average, the length of its life is much longer in captivity which averages between 40 to 50 years. Based on historical records, the oldest known crane lived to the age of 65 years – the longest ever recorded for a captive crane. This may be attributed to the fact that there are very minimal sources of threats in captivity other than getting diseases. Furthermore, there are more dangers present in the wild like human interference and predation.
Habitat: Just like storks and ibises, the red-crowned crane prefers living near bodies of shallow water like wetlands, marshes, swamps, and mudflats. This is due to the fact that they mostly feed on aquatic animals. However, a good number of red-crowned cranes prefer marshes with deep water as their long legs can allow them to still walk through the water.
Mostly, these birds prefer temperate regions because they are migratory birds. On top of that, there had also been records where some colonies have lived in agricultural areas.
Distribution: What makes the red-crowned crane of Japan so special is the fact that it is the second rarest crane in the world. They can only be found in small colonies in China, Japan, and certain parts of Eastern Siberia. There are two classifications of these birds, actually. There are migratory birds that live in the wetlands of East Asia: China, Japan, and Korea. However, the non-migratory kind lives in Hokkaido in Japan. Its number has been closely observed and recorded by Birdlife International.
Current Status: Currently, the red-crowned crane is considered as an ‘Endangered’ species by the IUCN Red List of Threatened Species. This is primarily due to the fact that it can only be found in small colonies in certain parts of East Asia. There are roughly 2,700 of these birds in the wild where the majority of its population resides in Japan.
Details about the Japanese Red-Crowned crane
How were they discovered?
These birds were first described in the year 1776 by a scientist named Statius Muller. Since then, it has been closely studied and observed by zoologists and scientists all over the world, primarily due to its rarity. It holds such an important role in culture in many East Asian countries and has been depicted repeatedly in ancient artworks, like paintings and drawings. They are also repeatedly mentioned in literary works like poetry, novels, and the like. It has been continuously admired through the centuries and is considered as one of the most special species of birds in the world.
What are their distinct features?
It can easily be confused with other species of cranes and even storks because of its white plumage. However, it has a number of special, distinct features as well. The most iconic physical feature that this particular bird has is the red bare skin it has on the top of its head. This gives off the “crown” it is commonly described with. This red skin becomes much brighter during the breeding period, a clear indication that it is looking for a mate.
When their wings are not stretched out to full length, the black tips of their wings look like dark tails. But in reality, their tail feathers are actually white and it is the secondary plumage of their wings that are black. Their cheek, throat, and necks are colored black, especially for males. Females, on the other hand, are pearly grey instead of black. Both have greenish colored bills which are short but thin and pointed. Their legs are either color dark grey or greyish black. Their eyes are small and beady which are normally in the dark brown shade.
What makes this species of bird distinct from others is the fact that it has a very large wingspan. This allows the crane to travel far distance at swift speeds despite their overall weight. They are actually considered as one of the world’s largest birds.
Where do they live?
Since these birds are known to be migratory, it means that they have periodic habitat changes all year-round. During the springtime and summertime, these birds are usually found breeding in colder regions like Easter Siberia, China, and Mongolia. Then, for the winter season they travel to areas with much milder snow like in Korea, and Japan. Some birds even travel to tropical destinations in Taiwan and China. Interestingly as well, there are non-migratory variants of these birds located in Hokkaido.
Both kinds of birds prefer living in rice paddy fields, grassy mudflats, wetlands, and rivers. When the conditions become too frigid for their comfort, they stay mainly in rice paddy fields where they prefer nesting in rice gleanings.
How do they behave?
Interestingly, these kinds of birds usually forage and live in flocks where the flock sizes are usually small in number. Usually, when these birds forage for food they either do it in groups or in pairs. However, there is a time when they have been observed to forage for food alone. Roosting, or resting, is always done in groups and never solitarily.
Interestingly, these birds are known to interact with other species of birds and animals. When around small animals like owls, falcons, and the like they are usually less aggressive. They allow these small species of birds to hunt near their nests. However, they behave rather differently in front of much larger animals. These usually behave quite aggressively against them because they are severely territorial birds, especially when they are nesting.
Japanese red-crowned crane love to dance – What is interesting about this kind of bird is that male birds often performs a ritualistic dance routine when trying to court female birds. The pair usually moves towards each other in rhythmic motions until they become close. They will move their heads in unison. This, as believed by zoologists, is the birds’ way of expressing happiness and excitement. They also use this as a way to strengthen their bond with their partners.
What do they eat?
This species of bird has a more varied diet and are known to be omnivorous. They can eat aquatic invertebrates like insects, worms, and the like. They also feed on small fishes and amphibians. Small mammals like rats are also a part of their diet. When food is scarce, especially due to changing seasons, these birds rely on berries, corns, and even grains. This is especially true for those birds that live in agricultural areas.
They usually use their pointed beaks to peck at their food, using the pointed end like a spear to easily catch moving prey. They use their long legs to walk in the mud or the shallow water while watching their prey move about. They would do this silently and then swiftly use their beaks to jab at their prey.
How do they reproduce?
Just like most birds of its kind (or other relative cranes and storks), the red-crowned crane is a monogamous bird. But their partnership lasts only up to a year or a few years, unlike other birds who stay with one mate for a lifetime. Usually, a male and female crane stay together until the next breeding season. Sometimes, they stay together for several breeding seasons as well.
Japan’s red-crowned cranes’ dance – This particular method is used to communicate with the opposite sex during mating season. The males usually perform the dance first and wait for the female to respond by dancing back. They then use the dance to create a special bond with each other before officially copulating.
The dance usually involves a few bows, leaps, and even head bobbing. Other gestures are also used like wobbling heads in unison. There are also mating calls, or ‘unison calls’, used together with this dance.
On every breeding season, a female would lay two eggs where there is a 50% mortality rate. Oftentimes, the other chick dies because the parent chooses only one to take care of. There are special cases where both chicks survive until they fledge after two months of nursing. The sexual maturity of a crane can be reached in no less than two years. Usually after fledging the birds can become independent and form home ranges within the range of their parents. They will start to separate when they are nearing sexual maturity.
Usually, both parents take turns in taking care of the young while the other forage for food. They rarely leave the nest unattended due to the presence of predators like large birds. Predation is another factor causing high mortality in crane chicks.
Cultural importance of the Japanese red-crowned crane
For the Japanese, and many East Asian cultures, the red-crowned crane is a sign of a long life. It is believed, in the earlier times, that crane can live up to a thousand years. It was also believed that they can grant wishes and prayers in exchange for an act of self-sacrifice. Since these birds are also monogamous, it is a symbol of loyalty and life. They are also a symbol of strength as they can fly distances when migrating. The red-crowned crane mating calls are considered a part of the 100 Best Soundscapes of Japan, because of its impressive strength and uniqueness.
Inspirations from the Japanese red-crowned crane dance – There are some performances, especially traditional dances which have been designed similarly to a pair of red-crowned cranes dancing. It is believed that it is a sign of true love, faith, and loyalty.
Threats to the life of the Japanese red-crowned crane of Hokkaido
One of the major causes of their population decline would be their loss of habitat. Through the decade's massive human habitation has caused a severe change in the landscape. These birds are forced to adapt to the new surroundings, but many individuals fail to do so. Natural threats are also common which come from the predation of large animals. This starts with the nest when 50% of eggs (and chicks) do not survive due to predation. They can easily protect themselves because of their size and speed, where they can easily outfly or outrun a predator. They can even use their beaks to attack their predators. However, it goes without saying that they have difficulty protecting their young.
Conservation of the Japanese red-crowned crane
In many parts of East Asia, this bird has been considered as a Special Natural Monument. This means that hunting for and trapping these birds are strictly prohibited. Large fines are put in place for the enforcement of these regulations. The difficult part about this is the fact that this natural monument declaration can only protect the bird but not its habitat. In the later years, and the past decade, there had been efforts of rehabilitating the natural habitats of red-crowned cranes and producing wildlife preserves for their nesting grounds. They also have wintering grounds where they can migrate to during the migratory season. This is in hopes that they can increase their numbers in the wild.
In the recent years, there had been a motion as well to return all the birds in captivity back into the wild. This is to help increase the population of the birds all over the world. There had also been education programs set up to teach locals how to protect and cohabit with this grand birds.