Study On Pheasant-tailed Jacana

This paper reports the results of the ecology research of pheasant-tailed jacana Hydrophasianus Chirurgus in Zhaoqing, Guangdong province. There live about 1,500 individuals of this bird, which knows as the largest population in China. The habitats where they live were plant with Gordon Euryale Euryale ferox Salisb.1. POPULATIONThose birds come to Zhaoqing in early April every year. Most of them finished changing the feather and ready to mate in the end of April. They begin mate in the beginning of May. From then on, the population was kept increasing rapidly, until it reached the top 1500 in the beginning of September. As migration begins in the end of August, the population was decreasing. There are only about 10 left during the winter.2. REPRODUCTIONIn order to gain an advantage of opponent, the birds use all kinds of methods, including song and dancing to attract opposite sex. We have record 15 kinds of song of the birds, 9 of them have relationship with reproduction.One female always mate with more than one mates. The average ratio is one female mate with 1.86 males (population sex ratio ♀ : ♂ = 1 : 2.24 ). The couples occupy certain exclusive territory. The territory of a female includes all her husbands' territory.Mating was take place in afternoon, whereas laying egg occurs in morning. A clutch always has four eggs. The interval of female's laying every egg is 23-25 hours. Eggs was put direct on a Gordon Euryale leaf or in the nest made by float grass.22~26days later, the eggs hatch. The chicken can walk and feed themselves in half hour after the hatch. Male keep watching on danger or the bad weather. 7 weeks later, the young birds can flight.3. DIETPheasant tailed jacana is polyphagia. The diet includes insects, frogs, fishs, mollusks, corns and nectars.4. MIGRATIONThe pheasant-tailed jacanas in Zhaoqing are migratory. The forthgoer of this bird arrive Zhaoqing in April, began migrate away in the middle of September. The growth of Gordon Euryale is relevant to the distribution of those birds, but not much to do with their leaving. In autumn, they migrate away scatteredly or in groups. Before migrate, they spend nearly whole daytime in hunting and foraging. Bit by bit, the number of remains drops down from more than 1,200 to less than 30. The remains will stay there during the winter.4. CONSERVATIONEven in their blossom, the pheasant-tailed jacanas are endangered by the human's activity in Zhaoqing. Industry exploits more and more farmland. As a result, habitats of pheasant-tailed jacana shrink rapidly. Moreover, the uses of pesticide which can poison the chicken threaten the population development. In order to change this awful status, the government established wetland conservation. It gives the jacana more or less a promising future.This research was carried out from Oct, 2003 to Nov, 2004.