台灣雉尾水雉的生殖生物學

Breeding Biology of Pheasant-tailed Jacana Hydrophasianus chirurgus in Taiwan

陳德治(Te-Chih Chen)

指導教授 ： 林曜松

共同指導教授 ： 丁宗蘇

國立臺灣大學/生命科學院/生態學與演化生物學研究所/博士(2008年)

https://doi.org/10.6342/NTU.2008.00858

摘要

台灣的雉尾水雉因棲地破壞導致族群數量迅速減少，引起重視並展開復育工作，但卻缺乏詳盡的研究資料，而生殖生物學資料在擬定保育或經營管理策略時可提供有用的參考資訊，本研究於2002~2007年，在台南縣雉尾水雉主要繁殖及度冬的棲地長期觀察與記錄其族群的數量變化以及各項生殖生物學資料，並蒐集各項環境因子資料，尋求其對繁殖成功率可能的影響或關聯性。研究期間共記錄395巢，1466個卵，孵化744隻雛鳥，群集分佈在數個繁殖區，環境因子中僅有巢與最近的河流直線距離與雛鳥20天存活率之間有顯著的正相關，可能和颱風豪雨常造成鄰近河流的菱角田潰堤，使巢卵及雛鳥流失，導致繁殖失敗有關，因此在保育計畫中必須針對群集的繁殖區重點加以保護，並預防豪雨的危害。
本研究第一次發現雉尾水雉雄鳥的殺嬰行為，並深入探究其機制和生殖上的適應性及對族群動態的影響。從結果推論雉尾水雉雄鳥利用殺嬰行為作為產卵後確認父性的方法，以避免將孵卵及育雛的生殖能量投資在非婚生子代身上。殺嬰行為對整體繁殖率的影響目前並不清楚，尚需更多的研究來探討。
本研究從行為活動時間分配模式探討婚配制度的演化，發現補充巢假說是最符合雉尾水雉一妻多夫制度的演化機制。雄鳥的日活動週期顯示生殖行為在繁殖後期集中於正午時段，雄鳥頻繁回巢孵卵以保護卵，避免正午時的高溫及強烈紫外線傷害。

關鍵字

水雉科 ； 繁殖生物學 ； 殺嬰 ； 婚配制度 ； 日活動模式

並列摘要

The population size of Pheasant-tailed Jacana in Taiwan have greatly declined due to habitat destruction . The population decline has attracted attention and various protective actions have been taken. However, few studies have done on the Pheasant-tailed Jacana. Understanding the breeding biology of Pheasant-tailed Jacana is critical in making conservation actions or management strategies. This study was conducted from year 2002 to 2007. I recorded the population dynamics and breeding activities of Pheasant-tailed Jacana in Tainan County, the main breeding and wintering area in Taiwan. I also measured and tested the relationships between environmental variables and the breeding success rate. During the study periods, I observed 395 nests, 1466 eggs and 744 chicks. The distribution of nests was in clumps in some breeding areas. The 20 days survival rate of fledgling was positively correlated with the nearest distance to river of the nest. Because the water chestnut fields adjacent to rivers were usually flooded by the heavy rains in typhoon season and subsequently the nests and chicks had a higher chance of nest failure. It is necessary to protect the main breeding areas that most nests located and to prevent the damages of floods.
This study is the first to report infanticide by male Pheasant-tailed Jacanas and to discuss its mechanisms and reproductive fitness. I suggest that male Pheasant-tailed Jacana may use infanticide as a strategy to avoid cuckoldry when the paternity of eggs is in doubt. Males can prevent investing extra-paired offsprings by infanticide. How infanticide influences the reproductive success rate of Pheasant-tailed Jacana was not clear and needed more studies.
This study also discussed the evolution of the mating system and the results were consistent with the predictions of the replacement clutches hypothesis in Pheasant-tailed Jacana. The time spent on breeding behaviors (mostly incubating behavior) of male jacanas peaked around noon in late breeding stage. I suggest this was due to the high air temperature of the study site during breeding season. Males had to stay in the nests to provide eggs and chicks protection from high temperature and ultraviolet ray.

並列關鍵字

Jacanidae ； breeding biology ； infanticide ； mating system ； diurnal pattern

參考文獻

Thong-aree, S., O. Khobkhet, and V. Lauhachinda. 1995. Breeding biology of Pheasant-tailed Jacana Hydrophasianus chirurgus in central Thailand. Nat. Hist. Bull. Siam Soc. 43:289-302.

中華民國野鳥學會. 1997. 中華民國野鳥學會鳥類資料庫: 水雉紀錄. 中華鳥會電腦檔.

Thong-aree, S., O. Khobkhet, V. Lauhachinda, and S. Pong-Umpai. 1995. Breeding biology of Pheasant-tailed Jacana Hydrophasianus chirurgus in central Thailand. Natural History Bulletin of The Siam Society 43:289-302.

Thong-aree, S., O. Khobkhet, V. Lauhachinda, and S. Pong-umpai. 1995. Breeding biology of Pheasant-tailed Jacana Hydrophasianus chirurgus in central Thailand. Natural History Bulletin of the SIAM Society 43:289-302.

Bekker, H., and B. Iuell. 2003. Habitat fragmentation due to infrastructure. Proceedings of the 2003 International Conference on Ecology and Transportation:1-14.