CRESTED IBISES
Standing about 75 centimeters tall, crested ibises (Nipponia nippon) are beautiful birds with white feathers, a red or pink face and a black downward curving bill. Indigenous to Japan, Korea, eastern China and eastern Russia, they are wading birds that make their homes in rice paddies and marshes. Crested ibises are known as ‘toki’ in Japan. In Japanese, ‘toki-iro’ (toki-color) is the characteristic pink-ish hue seen as the ibis flies overhead. The scientific name "Nipponia nippon" comes from the Japanese name for Japan, "Nippon." [Source: William Severud, Animal Diversity Web (ADW) /=]
Crested ibises are also known as Japanese crested ibises and Asian crested ibises. Designated one of the Japan's special natural treasures, they were common around the country in the Edo period (1603-1867). However, the number of the birds dramatically decreased because of overhunting, environmental problems and other reasons. At the beginning of the 20th century crested ibises were found in China, Japan, Korea, Taiwan and the Russian Far East. About 1,400 crested ibises live in China today, up from seven in 1981. As of 2022, nearly 500 lived on Sado Island, Japan, where there were none in 2008. They now draw tourists and represent a rare conservation success story.
The crested ibis is stockier and has shorter legs than the egrets and herons commonly seen in Japan. In the autumn and winter their plumage turns a pinkish-peach "ibis color." They feed on a large variety of mud-dwelling creatures, particularly loaches. When crested ibises are ready to mate they secret a black substance which they rub on their feathers. In January 2010, birds with the gray feathers produced by the process were observed among the released birds.
Ibises are closely related to spoonbills They have relatively short legs and a sickle-shaped, downward-curving bill that allows them to probe in the mud for mud-dwelling creatures such as loach and snails. Sensitive cells near the tip of the bill enable them to locate prey throughout vibrations and feel. Ibises spend much of their time in wetlands and nest there. They often move from place to place in large colonies. There are 26 species of ibis. Many species are endangered or critically endangered. Ibises are featured prominently in Egyptian mythology.
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Crested Ibis Habitat and Where They Live
Crested ibises favor wetlands such as marshes and swamps but can also be found in temperate forests, agricultural areas and mountains up to elevations of 1000 meters (3281 feet). During the breeding season they tend to forage and roost within their territories, but in the post-breeding season they may forage in flocks up to 20 kilometers from their roosting sites.
Wetlands are important foraging areas for crested ibises but due to human development and disturbance is such areas, ibises are thought to have moved from wetland areas with large human populations to mountainous areas. Mountainous regions in the crested ibis range do not have many natural wetlands, they often use rice paddies as substitutes and can be seen foraging there. Habitat preferences change seasonally. Breeding regions in China are at about 1000 meters (3281 feet) above sea level, while post-breeding regions are up to 500 meters (1640 feet). In Japan they are closer to sea level.
Crested ibises once ranged throughout temperate East Asia — from central China to Hokkaido, Japan and from southeastern Siberia to Taiwan — but are now restricted to several populations in China and one on Sado Island, Japan. Northern populations traditionally migrated south in autumn while more southern populations tended to remain in the same area. [Source: William Severud, Animal Diversity Web (ADW) /=]
Crested Ibis Characteristics
Crested ibises are medium-sized ibises, with an average weight of around one kilogram (2.2 pounds and an average length is 75 centimeters (29.5 inches). Their average wingspan is 1.4 meters (4.6 feet). They are endothermic (use their metabolism to generate heat and regulate body temperature independent of the temperatures around them) and warm-blooded (homoiothermic, have a constant body temperature, usually higher than the temperature of their surroundings). /=\ Sexual Dimorphism (differences between males and females) is not present: Both sexes are roughly equal in size and look similar. [Source: William Severud, Animal Diversity Web (ADW) /=]
The wings of crested ibises are long. Their tail is rounded. The plumage is white tinged with pink, and appears pink when seen from below in flight. The bill is long and curved, colored black with a red tip. The face is featherless and red. The eye is ringed with yellow and has a red iris. The red to brown legs are relatively short with webbed toes. The neck is also relatively short and covered with a mane of narrow feathers which hang to the base of the neck. A large crest sits on the nape — the source of the name crested ibis. . During the breeding season, the head and upper body turn gray, while the rest of the body remains unchanged.
A captive crested ibis lived to be 26 years old. The maximum breeding age is estimated to be 16 years. Chicks experience a 43 percent mortality rate in their first year. Survival increases to 19 percent for on-year-olds and then is five percent for every year after that.Egg hatching success is 80.2 percent.
Crested Ibis Food, Predators and Eating Behavior
Crested ibises are recognized as carnivores (eat meat or animal parts), piscivores (eat fish), insectivores (eat insects), molluscivores (eat mollusks) and vermivores (eat worms). Animal foods include amphibians, fish, insects, terrestrial non-insect arthropods mollusks, terrestrial worms and aquatic crustaceans. Among the plant foods they eat are seeds, grains and nuts. [Source: William Severud, Animal Diversity Web (ADW) /=] /=\
Wetlands have traditionally been important foraging areas for crested ibises. Among the creature consumed there have been fish ushc as carp, catfish, eels, weatherfish, frogs, newts, river crabs, crayfish, water-scavenger beetles, diving beetles, beetle larvae, crickets, snails, mussels, and earthworms. Some of these animals can be found in rice paddies. Stomach contents of birds from Korea have revealed rice gains. Crested ibises that forage in rice paddies often eat a lot of loaches.
Crested ibises like to in shallow, flooded, muddy habitats regions, not deeper than the length of their legs — 10 to 15 centimeters. They use their beaks to probe into the mud as the ibises walk slowly, stopping as when they find food. Once a food item is taken, it is shaken several times in the water — perhaps to clean it off — before being swallowed. Some birds have a preference for feeding along mud walls of rice paddies. If a pair of ibises locates a cluster of prey, the larger individual shoves the smaller one aside and will dominate the find. Throughout winter, ibises will visit several feeding areas within the same general area.
Crested ibises, especially younger ones, are preyed upon by snakes (especially king ratsnakes), Siberian weasels, yellow-throated martens and large birds of prey such as eagles, kites, goshawks, and kestrels. Crows have been observed destroying nests and preying on eggs.
Crested Ibis Behavior
Crested ibises fly and are diurnal (active during the daytime), motile (move around as opposed to being stationary), migratory (make seasonal movements between regions, such as between breeding and wintering grounds), sedentary (remain in the same area) and territorial (defend an area within the home range). Their average territory size is three square kilometers. [Source: William Severud, Animal Diversity Web (ADW) /=]
Crested ibises flock outside of the breeding season. It is thought that those in the southern part of their range in China were colonial nesters — living together in groups or in close proximity to each other — because the habitat was suitable for that and populations were sedentary. Habitats are more marginal in Japan and eastern Russia and populations are migratory there. All crested ibises are solitary nesters who defend their territory from rivals. /=\
According to Animal Diversity Web: Crested ibises are unique in that breeding (nuptial) plumage occurs as a result of cosmetic application of a waxy, tar-like substance. The behavior of application is known as ‘daubing’. Daubing behavior follows bathing, and consists of applying the dark substance to the feathers of the head, neck, back, and upper wing coverts. The substance is excreted from specialized skin on the head and neck. Daubing behavior is exhibited during the winter, just prior to the first courtship behaviors. The development of nuptial plumage in Crested ibises seems to be unique among birds.
Cretsed ibises communicate with vision and sound and sense using vision, touch, sound and chemicals usually detected with smell. Allopreening (the grooming of a bird's feathers by another bird) has been observed in crested ibises. This behavior is initiated by one individual gently nibbling at the red tip of another’s beak. The head, neck, and upper back of the recipient is allopreened. The crest of the recipient is usually raised when the nape is allopreened.
While feeding, resting, and preening, Crested ibises are silent. Before flight, a low ‘gak’ is emitted while in an upright posture. The call is repeated several times before taking to the air. If flushed, these ibises will emit a rapid series of ‘gak-gak-gak’ calls. This seems to be a high intensity alarm call, while the single ‘gak’ may function as an alarm as well as a contact call. The nest is defended against rivals from their own species by threat displays including wing flapping, head extension, stretch-and-snap, and pursuit flight displays. The crest is used in sexual display.
Crested Ibis Mating, Reproduction and Offspring
Crested ibises are monogamous (having one mate at a time) and remain with their mate throughout the year. They engage in seasonal breeding, breeding once annually usually from March through August. The number of eggs laid each season ranges from one to five, averaging three eggs laid at one or two day intervals. Eggs are 6.3 to 6.8 centimeters long, and weigh 65 to 75 grams each. Coloration is blue-gray with brown spots. The time to hatching ranges from 26 to 30 days. The average fledging age is 45 days, with independence occurring on average at five months. On average males and females reach sexual or reproductive maturity at three years. [Source:William Severud, Animal Diversity Web (ADW) /=]
William Severud wrote in Animal Diversity Web: Courtship behavior begins in January when crested ibises begin to display. One bird approaches the other with nesting material in its bill while bobbing its head. If the other bird accepts the material, the male will stand on the female's back in a pseudo-copulatory display. This display is repeated if another ibis approaches. If the material is not accepted, the rejected ibis will carry the material for many days, soliciting other ibises for pairing. In actual copulation sequences, the pair will approach each other with crests raised. They then touch beaks and allopreen. The female crouches and shakes her head, while the male mounts and wags his tail. /=\
Crested ibises nest in mountainous areas. Both sexes construct a nest measuring about 50 to 70 centimeters across from twigs and lined with moss and leaves. In China, Chinese red pine and Chinese cork oak are both preferred nesting trees, although other trees have also been used. Crested ibises are altricial. This means that young are born relatively underdeveloped and are unable to feed or care for themselves or move independently for a period of time after birth. Egg hatching success is 80.2 percent. Egg losses can be due to infertility, predation, and human disturbance. Both males and females take on parental duties. During the pre-birth, pre-weaning and pre-independence stage of young provisioning and protecting are done by males and females.
Nests are usually at the same places every year. Both sexes incubate the eggs beginning in mid-April and lasting about one month.. Re-nesting takes place if eggs are lost to predators. Chicks hatch in mid-May with a bald head, light gray down, and orange-red legs. Offspring grow rapidly, fed on a diet of regurgitated food from both parents. Both parents perform feeding visits and feeding bouts throughout the breeding season. Chick mortality factors include food shortage, predation, and human disturbance. At about one month old, chicks begin to walk on branches adjacent to the nest. Chicks remain near the nest tree until families gather in flocks for winter in early September.
Endangered Crested Ibis in Japan
On the International Union for Conservation of Nature (IUCN) Red List crested ibises are listed as Endangered. On the US Federal List they are classified as Endangered. In CITES (Convention on International Trade in Endangered Species of Wild) they are in Appendix I, which lists species that are the most endangered among CITES-listed animals and plants. [Source: William Severud, Animal Diversity Web (ADW) /=]
The crested ibis was protected in Japan during the Edo period (1603-1867). Beginning in the Meiji period in 1868 the protective measures were abandoned and the birds were hunted for their beautiful feathers as well as their meat, which was thought to have special medicinal and nutritional value.
Over the years crested ibises have been killed as agricultural pests and sickened and killed by pesticides and fertilizers. Deforestation disrupted their nesting sites. By the 1930s, only small populations survived around the Sea of Japan in central Honshu. Sado Island, an island in the Japan Sea about 25 miles offshore from central Honshu, was the home the of the last wild populations. The last natural breeding was confirmed in 1976 on Sado Island. In 1981, only five crested ibises remained in Japan and naturalists decided to capture them and try to breed them artificially. The last pure-bred Japanese crested ibis died at the age of 36 in October 2003. Artificial breeding didn't work. Crested ibises had also disappeared from China, Korea and Russia and looked as if the bird was doomed to extinction.
Return of the Crested Ibis to Japan
Just when all hope was about lost, a population of wild crested ibises was found in the mountains of Yang County in Shanxi province central China. The Chinese government immediately set up program to protect and artificially breed the birds. The program was a success. By 2000 there were 150 wild birds and 200 ones artificially-bred from seven original birds. To protect the remnant population nests were observed and predators driven away by volunteers. During food shortages, loaches were placed in local rice paddies for the birds to feed on. Nestlings too weak to compete with siblings for food were given artificial feedings. Education aimed at villagers living near the ibises was undertaken on measures were taken to preserve habitat, ban hunting, and forbid pesticide use. A major project was carried out, with Japanese help, near Xian in Yangxian district that encourages farmers in area where the birds live to stop using chemical fertilizers and pesticides.
In 1999, China began loaning pairs of crested ibises to Japan. Sado Crested Ibis Conservation Center was established on Sado Island. In May 1999, an egg produced by crested ibis given to Japan by China hatched at the Sado Conservation Center. It was the first time a crested ibis had been hatched in Japan since they disappeared. The event received a lot of media attention. Afterwards more chicks were born. Breeding is being carried by coupling male and female descendants of Yu Yo — the first descendant of a the Chinese pair brought to Japan. One problem with the system is inbreeding. To address this problem birds are being brought in from the outside. But this plan has disrupted by a ban on importing birds because of worries about bird flu. As of July 2007, about 107 Japanese crested ibises had been bred from Chinese-born crested ibises.
At the Sado center the ibises practice flying, hunt for food and learn to coexist with people. The 4000-square-meter, acclimation cages recreates a natural habitat with trees and rice paddies. Food includes loaches, worms and insects. Staff plant and harvest rice inside the enclosure. "Ibises are nervous and timid birds, so it's important to raise them until they are comfortable catching food in relatively close proximity to people," Yukio Hirono, the environment ministry's chief nature protection officer, told the Yomiuri Shimbun. .
In March 2010, a marten entered a bird cage on Sado Island containing 11 ibises being prepared for release into the wild and killed nine of the birds. A marten is small weasel-like animal. It entered the cage through a small hole and climbed a tree and killed the birds. Only one of the birds was eaten. The others are believed to have been killed for the fun of it. One of the birds that escaped had received training to escape from small predators. Video images from a security camera show the marten entering the cage and scampering around. But no one was watching the video when the attack occurred. At the time there were still more than 100 ibises living in captivity. The $14 million cage were the tragedy happened is 15 meters tall and covers 4,000 square meters. It encloses rice terraces, ponds and trees and was intended to duplicate the wild landscape of the birds.
Releasing Crested Ibises Into the Wild in Japan
At the Sado Conservation Center crested ibises have been bred with the goal of releasing them in the wild. The aim of the facility has been to create an environment close to the natural environment of ibises. The key to returning ibises to the wild is to encourage their natural instincts such as catching their own food and nesting. The ibises prepared for release in the wild on Sado island have been rained inside a 80-meter-long, 15-meter-high, and 50-meter wide cages that has rice paddies ponds and other natural features like those on Sado Island. The birds are taught to eat loaches and Japanese bitterlings released into ponds for them and fly to avoid enemies such as cats and hawks. The program was modeled afer the one used to raise storks in Hyogo Prefecture. To provide enough food for the birds after release, farmers on Sado Island have been given subsidies to flood fields so loaches and other creatures that the ibises feed on can grow. A total of 78 birds had been released into the wild in five batches as of 2012. Five pairs laid eggs in 2010, and seven pairs in 2011. However, some eggs fell out of nests and others were not fertilized. Therefore, no chicks were hatched from the eggs.
In September 2008, 10 crested ibises were released into the wild on Sado Island with a team of government officials and volunteers keeping an eye on them. It was the first time the birds had flown freely in the wild since 1981. A week after the were released, eight were confirmed to be healthy and good condition. Six of the birds were outfit with transmitters and GPS devices, so their locations could be determined. They were spotted in various locations including rice paddies, where they were seen looking for food. There were some worries about the ibises scattering to different locations on the island. Ibises usually stick together in groups. A year after 10 were released in 2008 the whereabouts of only seven was known. The released ibis failed to pair off and mate.The four males remained on Sado. The three females flew to Honshu. One male was observed making a nest for himself without a female companion. A female crested ibis was found dead on Sado in December 2008. It was thought to have been injured and then attacked by a tanuki. (racoon dog).
In September 2009, a second batch of ibises was released on Sado Island. Nineteen birds were released en masse to try to get them to form a flock. A month later seven of them formed a nine-bird flock with two others from the first batch released in 2008. In October 2010, 14 more ibises — eight males and six females as old as five years old — were released into the wild during the third release of the birds. This time the birds flew directly out of the 4,000-square-meter acclimation cage.
Of the 30 ibises released as of 2009,only two did not learn how or fly. After the release one flew straight into a bush and another went missing. In April 2010, eggs were found in the nest of a crested ibis in Sado island. It was the first time in 31 years that eggs had been laid by the species in Japan. The eggs were laid by a one-year-old female that mated in the wild with a three-year-old male. In the end the ibises threw all three of the eggs out of the nest. If a chick would have hatched it would have been the first wild hatch of ibises in Japan in 34 years. A second nesting resulting from mating between a 1-year-old female and 4-year-old male also failed to produce a hatching. In that case the nest was invaded by two crows while the ibises were away and the crows damaged the eggs.
As of September, 2016, a total of 174 ibises had been bred at seven locations throughout Japan, including the Environment Ministry's Sado Japanese Crested Ibis Conservation Center on Sado Island and 233 ibises had been released into the wild, and some of them have even flown to neighboring Honshu. As of 2022 nearly 500 crested ibises lived on Sado Island, Japan. They now draw tourists and represent a rare conservation success story. [Source: Yomiuri Shimbun, May 8, 2014, Wikipedia]
Image Sources: Wikimedia Commons
Text Sources: Animal Diversity Web animaldiversity.org ; National Geographic, Live Science, Natural History magazine, David Attenborough books, Daily Yomiuri, Yomiuri Shimbun, Japan National Tourist Organization (JNTO), New York Times, Washington Post, Los Angeles Times, Smithsonian magazine, Discover magazine, The New Yorker, Time, BBC, CNN, Reuters, Associated Press, AFP, Lonely Planet Guides, Wikipedia, The Guardian, Top Secret Animal Attack Files website and various books and other publications.
Last updated March 2025