台灣南部地區的鳥種組成與海拔分布

Avian Species Composition and Distribution along Elevation Gradient in the Southern Taiwan

本研究自1997年8月至2000年12月，在台灣南部地區的118個調查區中，共記錄到鳥類16目55科256種，若加上近年的文獻資料，本地區共有16目59科319種鳥類的記錄。其中包括台灣特有種15種及特有亞種67種，而屬於保育類的鳥類有78種。部分鳥種被記錄的調查區數少，在本研究所記錄的256種鳥類中，有106種被記錄的調查區數少於6個。依照本研究所劃分的7個海拔類別，我們分析其中140種具留鳥遷移屬性的鳥種，發現其物種豐富度隨著海拔梯度變化而呈現峰形分布的改變趨勢，如果同時將其它緯度遷移候鳥納入分析，則會減緩其峰形分布的改變趨勢，但兩者都是以1,500-1,999m海拔類別記錄到最高的鳥種數。而各海拔類別間的鳥種組成則以500-999m與1,000-1,499m及1,500-1,999m與2,000-2,499m這兩組海拔類別間具有較高的相似性。台灣南部地區鳥種豐富度與海拔梯度間呈現峰形分布可能與人為干擾、初級生產力、歷史地質事件及生物性競爭等因素有關，而在探討物種豐富度的分布時必須注意到調查努力量及分析類群本身的差異對結果所可能造成的影響。 An inventory survey of avifauna in the southern Taiwan was conducted in August 1997 toDecember 2000. A total of 256 species were recorded at 118 sites, of which 106 species were found onlyat less than 6 sites. When the species that had been reported in literature were also taken into account,there were a total of 319 species in 16 orders and 59 families with 15 endemic species, 67 endemicsubspecies, and 78 protected species in the southern Taiwan. The species richness was highest at 1,500-1,999m in elevations, while the similarity coefficient were highest between 500-999m and 1,000-1,499m,and also between 1,500-1,999m and 2,000-2,500m. There was a hump-shaped relationship between thespecies richness and the elevation gradient, possibly due to human disturbance, primary productivity,historical vicariance, and biotic competition. Sampling effort and functional groups varieties, such asforaging guilds or migrant status, should be considered in the examination of avian diversity anddistribution.