Nipponia nippon

Geographic Range

Japanese 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. Northern populations migrated south in autumn; more southern populations were sedentary.

• Biogeographic Regions
• palearctic palearctic
  • native native

Habitat

Wetlands are important foraging areas for Japanese crested ibises. Due to human disturbance, ibises are thought to have moved from highly populated wetland areas to mountainous areas. Mountainous regions in the Japanese crested ibis range do not have many wetlands, so rice paddies are often used for foraging. Habitat preferences change seasonally. During the breeding season, these ibises forage and roost within their territories, but in the post-breeding season they may forage in large flocks up to 20 km from roosting sites. Breeding regions in China are at about 1000 m above sea level, while post-breeding regions are up to 500 m above sea level.

• Habitat Regions
• temperate temperate
• terrestrial terrestrial

• Terrestrial Biomes
• forest forest
• mountains mountains

• Wetlands
• marsh marsh
• swamp swamp

• Other Habitat Features
• agricultural agricultural

Physical Description

Japanese crested ibises are small among ibises, measuring about 56 cm in body length. The wings are long and the tail 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. During the breeding season, the head and upper body turn gray, while the rest of the body remains unchanged.

• Other Physical Features
• endothermic endothermic
• homoiothermic
• bilateral symmetry bilateral symmetry

• Sexual Dimorphism
• sexes alike

Reproduction

Japanese crested ibises are monogamous, remaining in pairs throughout the year.

Courtship behavior begins in January when Japanese 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.

• Mating System
• monogamous monogamous

Japanese crested ibises breed between March and August, raising one clutch per season. Clutch size varies between 1 and 5 eggs, averaging 3 eggs. They are laid at 1 or 2 day intervals. Eggs are 6.3 to 6.8 cm long, and weigh 65 to 75 g each. Coloration is blue-gray with brown spots. Japanese crested ibises nest in mountainous areas. Both sexes incubate the eggs for 26 to 30 days. They will re-nest if the eggs are lost to predators. Mean hatching success is 80.2%. Egg losses can be due to infertility, predation, and human disturbance. 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. Chick mortality factors include food shortage, predation, and human disturbance. At about one month old, chicks will 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. Fledging tends to occur at 45 days of age. Young become mature and capable of reproduction at 3 years.

• Key Reproductive Features
• iteroparous iteroparous
• seasonal breeding seasonal breeding
• gonochoric/gonochoristic/dioecious (sexes separate)
• sexual sexual
• oviparous oviparous

Both sexes construct a twig nest measuring about 50 to 70 cm across, lined with moss and leaves. In China, Chinese red pine ( Pinus massoniana ) and Chinese cork oak ( Quercus variabilis ) are both preferred nesting trees, although other trees have also been used. Incubation is also conducted by males and females, beginning in mid-April and lasting about 1 month. Chicks then hatch in mid-May. Both sexes exhibit feeding visits and feeding bouts throughout the breeding season. Nests are usually at the same sites year after year.

• Parental Investment
• altricial altricial
• pre-fertilization
  • provisioning
  • protecting
    • female
• pre-hatching/birth
  • provisioning
    • female
  • protecting
    • male
    • female
• pre-weaning/fledging
  • provisioning
    • male
    • female
  • protecting
    • male
    • female
• pre-independence
  • provisioning
    • male
    • female
  • protecting
    • male
    • female

Lifespan/Longevity

The maximum breeding age has been estimated as 16 years. Chicks exhibit about 43% mortality in their first year. Survival increases to 19% at 1 year, then stays steady at about 5% for remaining age classes. Egg hatching success is 80.2%. A captive Japanese crested ibis lived to 26 years old.

Behavior

Japanese crested ibises flock outside of the breeding season. It is thought that Japanese crested ibises were colonial nesters in the southern part of their range (China), because the habitat was more suitable and populations were sedentary. Habitats are more marginal in Japan and the former Soviet Union and populations are migratory there. All extant Japanese crested ibises are solitary nesters and will defend territory from rivals.

Allopreening has been observed in Japanese 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.

Japanese 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 Japanese crested ibises seems to be unique among birds.

• Key Behaviors
• flies
• diurnal diurnal
• motile motile
• migratory migratory
• sedentary sedentary
• territorial territorial

Communication and Perception

While feeding, resting, and preening, Japanese 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 conspecific rivals by threat displays including wing flapping, head extension, stretch-and-snap, and pursuit flight displays. The crest is used in sexual display.

• Communication Channels
• visual visual
• acoustic acoustic

• Perception Channels
• visual visual
• tactile tactile
• acoustic acoustic
• chemical chemical

Food Habits

Wetlands are important foraging areas for Japanese crested ibises. Animals consumed include fish ( carp , catfish , eels , weatherfish ), frogs , newts , river crabs, crayfish , water-scavenger beetles, diving beetles, beetle larvae , crickets , snails , mussels , and earthworms . Stomach contents from Korea have shown rice as well. Supplemental feeding with loach has also improved survival.

Japanese crested ibises feed in shallow flooded muddy regions, not deeper than their leg length (10 to 15 cm). Beaks are probed into the mud while the ibises walk slowly, stopping as they encounter a food item. Once a food item is taken, it is shaken several times in the water before being swallowed. A preference has been noted for feeding along mud walls of rice paddies. If a pair of ibises locates a cluster of prey, the larger individual will dominate the find. Throughout winter, ibises will visit several feeding areas within the same general area.

• Primary Diet
• carnivore carnivore
  • piscivore piscivore
  • insectivore insectivore
  • eats non-insect arthropods
  • molluscivore molluscivore
  • vermivore

• Animal Foods
• amphibians
• fish
• insects
• terrestrial non-insect arthropods
• mollusks
• terrestrial worms
• aquatic crustaceans

• Plant Foods
• seeds, grains, and nuts

Predation

Japanese crested ibises are preyed upon by snakes (especially king ratsnakes ( Elaphe carinata ), Siberian weasels ( Mustela sibirica ), yellow-throated martens ( Martes flavigula ), and large birds of prey such as eagles, kites, goshawks, and kestrels. Crows have been documented destroying nests and preying on eggs.

Ecosystem Roles

Japanese crested ibises are predators of smaller vertebrate and invertebrate animals. They also act as hosts to a variety of parasites.

Economic Importance for Humans: Positive

Endangered species, like Japanese crested ibises, draw ecotourism interest. Local economies may benefit from having Japanese crested ibises nest near them.

• Positive Impacts
• ecotourism ecotourism
• research and education

Economic Importance for Humans: Negative

Japanese crested ibises may trample newly planted rice paddies while foraging, and stomach contents have found rice as well. However, the rarity of these birds make their impact on crops negligible.

• Negative Impacts
• crop pest

Conservation Status

Japanese crested ibises were thought to be extinct in the wild until 1981, when a few wild birds were discovered in the mountains of Yang County, Shaanxi Province, China. Since rediscovery, measures have been taken to protect the remnant population. Nests are observed and predators driven away by volunteers. During food shortages, loach are stocked in local rice paddies. Nestlings too weak to compete with siblings for food are given artificial feedings. Education has also been undertaken on preserving habitat, banning hunting, and forbidding pesticide use. The wild population is now experiencing an upward growth trend. A successful captive breeding program had been ongoing since 1995. Two eggs were laid in Tama Zoological Park in Tokyo in March 2008. According to one population viability analysis, the major parameters affecting the fate of the population are environmental variation and catastrophes. Habitat loss, hunting, and environmental pollution were the dominant factors which brought about the catastrophic decline since the late nineteenth century. Low genetic diversity from this bottleneck may cause a limited ability to tolerate a wide range of environmental extremes and diseases, hindering reintroduction efforts in other regions of former ibis range.

Other Comments

Japanese 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."

Additional Links

Encyclopedia of Life

Contributors

Tanya Dewey (editor), Animal Diversity Web.

William Severud (author), Northern Michigan University, Alec R. Lindsay (editor, instructor), Northern Michigan University.

References

Archibald, G., S. Lantis. 1978. Conservation of the Japanese crested ibis. Proceedings of the 1978 Conference of the Colonial Waterbird Group, 2: 1-15.

Fennell, C., B. King. 1964. New occurrences and recent distributional records of Korean birds. The Condor , 66: 239-246.

Li, X., D. Li, Y. Li, Z. Ma, T. Zhai. 2002. Habitat evalution for crested ibis: a GIS-based approach. Ecological Research , 17: 565-573.

Li, X., D. Li. 1998. Current state and the future of the crested ibis ( Nipponia nippon ): a case study by population viability analysis. Ecological Research , 13: 323-333.

Sanada, K. 2002. "Has the Japanese Crested Ibis Been Saved from Extinction?" (On-line). Nipponia. Accessed April 06, 2008 at http://web-japan.org/nipponia/nipponia23/en/topic/index.html .

Shi, D. 1991. The diet of the crested ibis and the food abundance during wandering season. Journal of Northwest University (additional edition) , 21: 37-42 (in Chinese).

Wingfield, J., S. Ishii, M. Kikuchi, S. Wakabayashi, H. Sakai, N. Yamaguchi, M. Wada, K. Chikatsuji. 2000. Biology of a critically endangered species, the toki (Japanese crested ibis) Nipponia nippon . Ibis , 142: 1-11.

Yu, X., N. Liu, Y. Xi, B. Lu. 2006. Reproductive success of the crested ibis Nipponia nippon . Bird Conservation International , 16: 325-343.

Zhang, B., S. Fang, Y. Xi. 2004. Low genetic diversity in the endangered crested ibis Nipponia nippon and implications for conservation. Bird Conservation International , 14: 183-190.

2003. Japanese Ibis Nipponia nippon . Pp. 298-299 in Grzimek's Animal Life Encyclopedia , Vol. 8, 2nd Edition. Detroit, New York, San Diego, San Francisco, Cleveland, New Haven, Waterville, London, Munich: Thomson Gale.