山 階 鳥 研 報(J. Yamashina Inst. Ornithol.),22: 70-76,1991

World's First Captive Breeding of the Japanese Crested Nipponia nippon

Li Fulai*

Abstract The breeding center for Japanese Crested was established in the Beijing Zoo in 1986, and today five Japanese Crested Ibises are managed at that center. They were taken as nestlings from the wild in Yangxian County, Shaanxi Province, . After careful rearing they are health in 1988. A pair of these , a female taken in 1985 and a male in 1986, were put for breeding in the same enclosure. Two eggs were laid on 13 and 15 June 1989, and two nestlings were hatched in July. In the morning of 8 July, a loud chirping was heard from the nest. We immediately went to inspect and found that the nestling was already out of the shell. The nestling was fully developed, but was dead from peck wounds on the head and abdomen. Concurrent with the hatching of the first nestling, the egg that was incubated under a domestic fowl, pipped. It hatched 10 July. Unfor- tunately this nestling died after 6 days. The incubation period was 25 days instead of 28 to 30 days recorded in the literature. This is the first capttive breeding for this .

Introduction

The Japanese Crested Ibis Nipponia nippon is one of the rarest birds in the world. It belongs to the category of under first-class protection in China and has been listed as one of the "birds under international protection" since 1960. Since China rediscovered the in 1981 much has been done to save it from . The number of Japanese Crested Ibises has increased from seven to 46 in the past eight years and encouraging results have been achieved in artificial breeding. Thanks to the Brehm Fund for International Bird Conservation for supporting to the Ibis Breeding Center, to Dr. George Archibald and Mr. Kiyoaki Ozaki for reading this paper.

History of Crested Ibis

According to the records ibises originated in the Cenozoic Era, some 60 million years ago. Japanese Crested Ibises existed extensively in the eastern part of Asia-north to the far eastern coast of the Soviet Union, south to Hainan Island and , west to the central part of China and east to the Japanese island. However, the number of crested ibises has drastically decreased in the past few decades and their distribution has rapidly shrunk. In Japan, the number of ibises was 31 in 1953 and only 11 in 1973. In January 1981 the Japanese captured the remaining five wild ibises. Together with the one they had kept in captivity since 1968, the birds were maintained for breeding and reproduction studies at the Ibis Protection Center on Sado Island. They never bred and and today,

Received 10 November 1989, accepted 9 April 1990. * The Ibis Breeding Center , Beijing Zoo, 13 Xi Zhi Men Wai St. Beijing China

70 World's First Captive Breeding of the Japanese Crested Ibis 71 only two remain. In recent years Ibis have not been reported in the USSR. On the Korean Peninsula 20 were reported in 1934, three in 1966, four in 1974 two in 1977 and none since 1980 (Yamashina et al. 1983). There are records of ibises in 14 of China's provinces in the 1930s. By 1958, how- ever, specimens could be collected only in Gansu, Shaanxi and Jiangsu provinces. In the 1960s they seemed to have disappeared altogether. In 1978 the State Council in- structed the Zoological Research Institute under the Chinese Academy of Sciences to look for ibises. A special investigation group conducted four investigations along different routes, visiting 13 provinces, travelling more than 50,000km before finally dis- covering seven Crested Ibises in Yangxian County, Shaanxi Province, in May 1981. The rediscovery of the Crested Ibises amazed the world. In order to protect these these "Criental jewels," the Forestry Ministry set up an "Ibis Protection and Observa- tion Station" in Yangxian County. Later, the "Crested Ibis Breeding Center" was set up in Beijing Zoo, through partial support from the Brehm Fund for International Bird Conservation.

Captive Breeding

The breeding center for Crested Ibises was established in the Beijing Zoo in 1986. After four years of study and breeding two nestlings were hatched in July 1989, the first captive breeding for this species. This success bodes well for efforts to protect the birds from extinction. Five Crested Ibises are now maintained in the Crested Ibis Breeding Center at Beijing Zoo. They were taken as nestlings from the last population of wild ibis in Yangxian County, Shaanxi Province. After careful rearing they have matured normally. A pair of these birds, a female caught in 1985 and a male caught in 1986, were put in the same enclosure for breeding in 1988. And in early 1989 the conditions for mating blossomed. Under natural conditions the egg-laying period for Crested Ibises is March-May. However, the temperature in Beijing is still low at that time. Therefore, as the weather permitted the birds were allowed to move about in their outdoor enclosure during the day and were shut in their indoor room at night. Crested Ibises like to build their stick nests in high places. Because they are sensitive to disturbance, in early spring before the birds were let outside, two baskets lined with twigs were placed at different heights in the outdoor enclosure, hoping that such might be chosen as nest sites. In early April the birds started nesting activities. They not only arranged the twigs in the baskets but very often picked twigs up from the ground and took them to the the baskets. In late April the couple began to mate and they built their nest in the higher basket, sometimes taking twigs from the lower basket. By late May the nest was basically completed. They stopped transporting large twigs and only carried to the nest smaller twigs and straw from the ground. The male and female alternated at the nest. In order to encourage them to lay eggs, apart from the regular food of artificial feed and eels, additional vitamins and minerals were added to the diet. 72 F. Li

Photo 1

Photo 2

Paoto 3

Photo 1. Eggs and nest of Japanese Crested Ibis (The front one is artificial). Photo 2. Hatching egg on 10. July, 1989. Photo 3. Three days old chick. World's First Captive Breeding of the Japanese Crested Ibis 73

Inducing birds to lay eggs with false eggs is a method often used for captive birds. Consequently we also placed a plastic "egg" in the nest of the ibises. As a result they began to stay long on their nest and one of the birds stayed in the nest overight. Egg were laid on June 13 and 15, and weighed 77g and 80g respectively. The eggs were long and oval in shape. The shells were grey with brown speckles, denser on the blunt side. However, because the ibis enclosure was located in a public area of the zoo, the noisy environment adversely affected the hatching of the ibises. Therefore, the eggs were taken out of the nest and placed to be hatched under domestic fowls. The ibis were disturbed to lose their eggs, so it was decided to place one egg back in their nest, so the ibis could hatch and rear their own chick. The second egg remained with the domestic fowl. On the morning of July 8 a loud chirping was heard from the adult ibises in the nest. We immediately went to inspect and found that the nestling had hatched, but was dead from peck from wounds on the head and abdomen. The incabation period was 25 days instead of 28 to 30 days recorded in the literature (Kuroda et al. 1985). Checking the other egg, the chick had already pecked the open shell and on July 10 it hatched. This was theworld's first Japanese Crested Ibis hatched under artificial breeding condi- tions. It weighed 57g and had a total length of 130mm. Its eyes were already open and its beak was straight and black with a pink tip. The whole upper body had sparse dark grey down and the down of the lower body was white. Its skin, the naked part of its tarsi and its feet were pink, and it had white claws. The nestlings of Crested Ibises grow slowly and are difficult to raise artificially. The first artificially hatched ibis survived only one week.

Field Observations From March to May 1986 we made a survey of the breeding habits of the ibises in Yangxian County (Li & Huang 1986). The three nesting areas visited were in the quiet valleys north of the county seat some 875m to 1,150m above sea level. The ibis like to make their nests in tall oaks with paddy fields and streams nearby where they can find food. The temperature there during this period was from three degrees to 30 degrees Centigrade. There was drizzle and high humidity. This finding provided us with a basis for creating a suitable environment for Crested Ibises in the arid Beijing area. Pairs of ibises are very affectionate. During non-breeding periods they live in groups and are very social. Very often in the early spring they perform courtship and copulation in the nesting areas whether they are in pairs or in small groups. During the nesting period they mate frequently and they often mate even during the incubation and hatching periods. During the mating period at the nests, the birds often lovingly preen the feathers of their spouses and gently call to each other. The couples often turn the eggs and tidy their nests and they alternate incubation duties. Sometime, the parent birds which have just left the nests turn back and bring twigs to the nests and show intimacy or hold "pseudo-mating". 74 F. Li

The three pairs of ibises in the three nesting areas all started to nest in late February and early March. However, there was great variation in their breeding chronology. One pair started on March 6 and took only 13 days to lay, while another pair took more than one month to do the same. The nests are built of dry twigs, leaves or hay and are about 25.4m from the ground. During the incubation and brooding periods the couple add twigs to the nest. The male bird brings more than the female bird. For some days before eggs are laid, the ibis alternate sitting in the nest. However, they are easily frightend and a bird leaves the nest upon the slightest disturbance. This is the prelude to incubation. Once eggs are laid the birds are reluctant to leave the nest. During the incubation period we made round-the-clock observations. We found that male and female ibises typically alternate incubation duties. They make several shifts during the day and one shift at night. Only one bird is found in the nest and none is seen waiting near the nest. On the first day of our observation we found at the No. 2 nest that the turning and cooling of the eggs by the parent birds were quite regular but early the next morning the bird on the nest was very uneasy. In the half hour between 6:00 and 6:30 it got up nine times. Later, it was proved that it was because the parent bird was in a state of great excitement at the birth of its nestlings. This change In behavior was a great help to us in judging whether the eggs had been hatched. Both the male and the female ibises share rearing tasks. Each day the two birds feed them 14 to 21 times, more frequently in the earlier period than in the latter period. This is because in the earlier period the parent birds stay longer in the nest as they have to warm the nestlings as well as to feed them, and the nestlings continuously ask for food. However, during the latter period, the parent birds stay bery briefly in the nest because they have mainly to feed the nestlings. They leave the nest immediately after the nestlings are fed and stay on some other branch to rest or fly away. In feeding their young the parent birds mainly let the nestlings peck food from their mouths. Before feeding the nestlings the parent birds regurgitate and often wipe out their mouths on the nest. Later in the rearing period, the parent birds regurgitate their food on the nest and let the nestlings pick at it for themselves.

Discussion

Ibises are very sensitive to changes in the environment and are easily frightened. The Ibises raised in the breeding center are all young birds taken from their nests in the nature reserve just before fledging. Maintained in captivity, they get on very well with their keepers. The ibises take delight in running after their keepers, fly to them when their names are called and even allow their keepers to touch them with their hands. However, they will suddenly cry out, fly away and even bump against the window panes or wire netting of their enclosure when they see strangers, find new objects or hear strange sounds. As a result, they often hurt their long beaks and they have to be fed by keepers because they can't get food by themselves. Therefore, we should do our best to create a tranquil environment for the ibises, and not disturb them or catch them at will. In order to accommodate their habit of digging in the ground we have planted a lawn for World's First Captive Breeding of the Japanese Crested Ibis 75

them. Most of the young ibises carried parasites when they were taken from the wild. Some were very seriously infected. One bird died just over a month after it had been taken from its nest because of a parasitic disease. Many experiments have been made to cure such parasitic diseases with the help of the veterinarians of Beijing Zoo. Favourable results have been obtained. By giving regular tests to the ibises and making efforts to prevent further infection, the health of the birds has been assured. The Crested Ibises are fed both artificial and natural foods. Ibises have been main- tained in several of the world's most famous zoos for many years, but only a few of them have successfully got the birds to reproduce. By making reference to both domestic and foreign data and combining the condi- tions of Beijing Zoo, the breeding centre has prepared artificial food for the Crested Ibises. By feeding them with artificial food and some natural food (namely eels), we have ensured that their need for nutrition is met and to their foraging instincts are ac- commodate. In the course of maintaing, breeding and rearing the ibises it has been found that the colour of the feathers of Crested Ibises at two years of age becomes grey during the breeding period and is similar to that of adult breeders. But judging from when female birds lay eggs and the mating activities of male birds, we find that Crested Ibises become sexually mature at three years of age. The ovulation period of ibises in Yangxian County is between February and April, and in Beijing in May and June. The delay is perhaps related the colder climate in Beijing. The incubation period of eggs of the Japanese Crestel Ibis is about 25 days. Most altricial birds have closed eyes during hatching, however, the Crested Ibis eyes are open during emergence from the shell.

References

Kurokawa, N. & Morioka, H. ed. 1985. World , and raising No. 8. Tokyo Zoo- logical Park Society. (in Japanese) Li, F. & Huang, S. 1986. A survey on reproductive habit of Nipponia nippon. Bulletin of Biology, 1986 (12): 6-8. Li, F. & Gao, X. 1989. Study on the after-baby moulting of the Crested Ibis, Chinese Wildlife (51): 21- 22. Yamashina, Y. & Nakanishi, G. ed. 1983. Newton Books, Nipponia nippon. pp. 301 Kyoikusha, Tokyo. (in Japanese) 76 F. Li

トキの飼育下におけ る初繁殖成功

1986年,北 京 動 物 園 に トキ増殖 セン タ ーが 設 け られ,現 在5羽 の トキが飼 育 され て い る 。 それ らは幼 鳥 時 に 中 国陜 西 省 洋 県 で 野 外 か ら捕 え られ た もの で あ る 。 こ の うち の1985年 生 れ の雌 と1986年 生 れ の 雄 を,繁 殖 の た め 同一 ケ ー ジに 収 容 した。1989年6月13日 と15日 に計2卵 が産 卵 され た 。 そ して7月 8日 の 朝1卵 が孵 化 した が,親 鳥 に つ つ か れ て死 亡 した 。 ニ ワ ト リの仮 母 に託 され て い た も う1卵 は,7

月10日 に孵 化 した が,残 念 な が ら6日 後 に死 亡 した 。 トキの抱 卵 日数 は文 献 に よる と28-30日 とさ れ て い る が,今 回 は25日 で あ った 。 本 例 は 飼 育 下 に お け る トキの初 繁 殖 成 功 記 録 で あ る(文 責 尾 崎 清 明)。

李福来;北 京動物園,中 華人民共和国北京市西外大街137号