金門島栗喉蜂虎單獨與集體營巢之生殖策略分析

Solitary and Colonial Breeding Strategies in Blue-tailed Bee-eaters (Merops philippinus) on Kinmen Island

王元均(Yuan-Jyun Wang)

指導教授 ： 袁孝維

國立臺灣大學/生物資源暨農學院/森林環境暨資源學研究所/碩士(2006年)

https://doi.org/10.6342/NTU.2006.00831

摘要

行集體營巢具有如共同攻擊天敵、資訊交換、增加群體覓食效益等好處，但同時也具有吸引天敵、種內托卵寄生、寄生蟲及疾病傳染等缺點，因此在不同大小的生殖群聚及生殖群聚內的不同巢位，對於其生殖表現都可能造成影響。金門島的栗喉蜂虎(Merops philippinus)正是採行集體營巢生殖方式。所以本研究的目的在於(1)比較栗喉蜂虎在單獨築巢與集體營巢間、集體營巢中不同大小的生殖群聚間的生殖表現與生殖者形態上的差異；(2)探討栗喉蜂虎在生殖群聚內巢位與生殖成功間的關係是否符合中央-邊緣模式。

本研究一共有CS(19個使用巢)、CM1跟CM2(皆為32巢)及CL(72巢)共4個不同大小的生殖群聚，以及21巢單獨築巢。結果顯示行集體營巢者被天敵捕食率顯著高於行單獨築巢者；在4個不同大小生殖群聚間亦發現大的生殖群聚(CL)的被天敵捕食率顯著高於中等大小的兩個生殖群聚(CM1&CM2)，推測這些現象可能是因為集體營巢易吸引天敵所致。本研究中僅在受天敵壓力最大的CL中發現有中央-邊緣模式出現，邊緣地區面臨較大的天敵捕食壓力可能是因為栗喉蜂虎主要的天敵為蛇及囓齒類等陸生動物，其入侵模式主要是由邊緣地區開始所致。研究結果發現行單獨築巢的蜂虎個體喙長要顯著的高於行集體巢者;在生殖群聚內亦發現在中央區域築巢的個體喙長要長於在邊緣區域築巢者。根據本研究的結果，我推測對金門島上的栗喉蜂虎而言，單獨築巢可能是較好的生殖策略，而喙長較長的個體可能是較會打鬥的優勢個體，因而可以先佔據可能有限的單獨築巢棲地，其次的選擇可能是生殖群聚裡的中央區域。

關鍵字

蜂虎 ； 單獨築巢 ； 集體營巢 ； 中央邊緣模式

並列摘要

Colonial breeding provides birds several advantages, such as mobbing, information- centre, and enhancing feeding efficiency. However, it might also bring some disadvantages, such as increasing chances of attracting predators, intra-specific parasite, nest-parasite and infectious diseases. Therefore, different sizes of colony and nest location have found to affect the reproductive success. The purposes of this study were to: (1) compare the reproductive success and morphological variables of Blue-tailed Bee-eaters (Merops philippinus) between solitary and colonial breeders and among different sizes of colony, and (2) examine if the nest location vs. reproductive success of Blue-tailed Bee-eaters fits the centre- periphery model.

Four colonies with sizes of 19 (CS), 36 (CM1), 36 (CM2) and 64 (CL), and 21 solitary nests were monitored in this study. Predation rates were significantly higher for colonial nests than solitary ones. Within colonial nests, larger colony (CL) was suffering significantly higher predation pressure than the two medium ones (CM1 and CM2). I only found the nest location vs. breeding success of CL fits the centre-periphery model, which might because bee-eaters’ major predators, snakes and rats, usually invading from the peripheral region. I also found the bill size was significantly longer for the solitary breeders than the colonial ones, and longer for the center than the peripheral ones for the colonial breeders. Based on the results, I proposed that solitary breeding might be a better strategy for the bee-eaters on Kinmen island. Individuals with longer bill might be the superior ones with a better fighting ability who could occupy the better but limited solitary nest sites, then the choice might go to the center location for colonial nesting.

並列關鍵字

Merops philippinus ； bee-eater ； solitary ； colony ； centre-periphery model

參考文獻

in central and peripheral nests of magellanic penguins

multiscale approach. Proceeding of The Royal Society of

Danchin, E., and R.H. Wagner. 1997. The evolution of

Barbosa, A., J. Moreno, S. Merino, and J. Potti. 1997. Breeding group size, nest position and breeding success in

nest:benefit and cost of colonial nesting in swallows.