臺灣本島外來種鵲鴝的繁殖生物學與巢位選擇

鵲鴝(Copsychus saularis)是二級洞巢者，會使用樹洞、建築物的孔洞、人工巢箱作為繁殖巢位，有明顯的領域行為，原生地位於南亞及東南亞，包含中國南方、印度、孟加拉、緬甸、泰國、寮國、柬埔寨、越南、馬來西亞、印尼等地。在台灣島，鵲鴝是由寵物貿易引入的外來種，1995年有第一筆野外紀錄，至今仍缺乏此物種的研究調查，未知其對生物多樣性的影響。本研究以台北市和新北市的6個都市公園為樣區，調查鵲鴝的族群密度、繁殖表現、巢位選擇，以建立鵲鴝在台灣引入地的基礎研究資料。2017年的調查結果：平均巢密度0.12 ± 0.08 per ha (n=6)，產卵期間4-8月，平均窩卵數4.3 ± 0.9 (n=8)，平均孵化率0.58 ± 0.48 (n=8)，平均離巢率0.5 ± 0.45 (n=8)。2018年的調查結果：平均巢密度0.18 ± 0.07 per ha (n=6)，產卵期間4-7月，平均窩卵數4.1 ± 0.8 (n=17)，平均孵化率0.58 ± 0.39 (n=17)，平均離巢率0.38 ± 0.34 (n=17)。兩年度的巢密度、繁殖表現均無顯著差異。巢位選擇以假說檢定比較巢位組與抽樣組的35個環境因子，僅有洞穴深度有顯著差異，代表鵲鴝偏好較深的樹洞，推測可能因為樹洞深度能提供良好的隱密性，較不易被天敵察覺與攻擊。

關鍵字

雀形目；二級洞巢者；繁殖成功率

並列摘要

The oriental magpie-robin (Copsychus saularis) is a secondary cavity nester which nests in tree holes, building holes, and artificial nesting boxes. It has obvious territorial behavior. It is native to South and Southeast Asia, including southern China, India, Bangladesh, Myanmar, Thailand, Laos, Cambodia, Vietnam, Malaysia, and Indonesia. In Taiwan, the oriental magpie-robin is an exotic species introduced by pet trade. In 1995, there was the first field record, but until now we still lack of research on this exotic species. Its impact on biodiversity is unknown. This study used six urban parks in Taipei City and New Taipei City as sample areas to survey the population density, reproductive performance and nest site selection of the oriental magpie-robin. The results of the survey in 2017: the average nest density was 0.12 ± 0.08 per ha (n=6), the breeding period was in April-August, the average clutch size was 4.3 ± 0.9 (n=8), and the average hatching rate was 0.58 ± 0.48 (n= 8), the average fledging success rate was 0.5 ± 0.45 (n = 8). The results of the survey in 2018: the average nest density was 0.18 ± 0.07 per ha (n=6), the breeding period was in April-July, the average clutch size was 4.1 ± 0.8 (n=17), and the average hatching rate was 0.58 ± 0.39 (n= 17), the average fledging success rate was 0.38 ± 0.34 (n = 17). There was no significant difference in nest density or reproductive performance between the two years. The nest site selection was based on the hypothesis test to compare the 35 environmental factors of the nest group and the sampling group. Only the cave depth has a significant difference, which represents the preference for deeper tree holes. Presumably It is because the tree hole depth can provide good concealment, and is less likely to be noticed and be attacked by predators.