玉山國家公園大分地區臺灣黑熊遺傳多樣性之初探

外文標題: 
Preliminary Study of Genetic Diversity of Formosa black bears(Ursus thibetanus formosanus) in Dafen of Yushan National Park
校院系所: 
屏東科技大學野生動物保育研究所
指導教授: 
黃美秀
翁國精
出版年份: 
2012年
主題類別: 
摘要: 

過去針對臺灣黑熊的遺傳研究,都是著重於亞種的分類,並沒有針對臺灣黑熊族群進行評估其遺傳多樣性,本實驗採用非侵入性採集法(Non-invasive sampling method),去收集黑熊樣本供實驗需要,此方法已被廣泛用來評估密度較低或活動範圍較大的物種。
本研究從2008年2月至2009年1月間,於玉山國家公園大分地區利用毛髮陷阱(Hair trap)收集臺灣黑熊之毛髮樣本,利用穿越線收集排遺樣本,利用擴增6組微衛星基因座來辨識黑熊個體,利用性別引子確認個體性別。
我們分析熊毛髮(n=112)及排遺樣本(n=290),6個基因座的PCR擴增成功率分別為47%及34%,且分別檢定出30及48個體,兩種樣本重複判定出13隻個體,共辨識出65隻不同的個體,其中27隻雌性、33隻雄性、5隻為未知性別,未達顯著偏離性別平衡。6個微衛星基因座之等位基因的數目為4-8個(6.33±0.151),個體鑑別率為1.381E-06;觀測異質度為0.754,與理論值接近(0.744),多態信息量(Polymorphism Information Content, PIC)皆大於0.5;結果顯示本研究採用雖然整體族群經哈溫定律平衡測試,顯著偏離哈溫平衡(p<0.05),但FIS值(近親交配指數,Inbreeding coefficient)為極小的0.013,此數值極小應可忽略的,大分地區的黑熊應為隨機交配。有90%(59/65)的黑熊個體在青剛櫟結果季(10月至隔年一月)出現在大分地區,其相對變化量與同時期的自動相機資料相符。
與21個北美洲的美洲黑熊與棕熊的遺傳多樣性相較,大分地區黑熊能處於一個高遺傳多樣性的狀況。本研究發現族群偏離哈溫定律平衡(Hardy-Weinberg equilibrium, HWE),但由於缺乏了長期追蹤個體的資料,與大分地區以外的樣本佐證,難以確實推測其原因。

外文摘要: 

Over the past decade, genetic studies of the Formosan black bear were forces on classification of the subspecies. There is no study of assess genetic diversity of Formosan black bear populations. Noninvasive sampling methods have been widely used to estimate elusiveness or abundance of animals. The Formosan black bear (Ursus thibetanus formosanus), an endemic subspecies of Asiatic black bear (U. thibetanus) inhabiting Taiwan, has been listed as a locally endangered species during past decades. Although intensive ecological research programs have been conducted in Yushan National Park (YNP) since 1998, there have not been attempts to estimate the bear abundance. It is difficult to collect data from range-free and small populations in remote and rugged terrain like our study area.
The area in study was searched for Formosan Black bear feces and sampled hair snared from baited traps from February 2008 to January 2009, in a monthly basis. For every sample was amplified using 6 microsatellite locus. We analyzed 112 hair and 290 fecal samples, which yielded 47% and 34% of the successful DNA amplification rates, respectively. The genotyping based on 5 microsatellite loci for individual identification indicated the presence of 30 and 48 individuals, from hair and fecal samples, respectively. As a result, a total of 65 different individuals were indentified and the population estimation was further conducted and discussed. The average number of alleles per locus was 6.33±1.51, ranging from 4 to 8. The overall observed heterozygosity was 0.754, which was close to the expected heterozygosity (0.744). The overall FIS value was 0.013. The result revealed an acceptable level of genetic diversity of the YNP population. Almost 90% were detected in the acorn season (October up to next January).
The masting season of Cyclobalanopsis glauca in 2008 likely attracted a highly dense congregation of bears. Considering the bear movement pattern for seeking food and the fact that all our effective samples collected in non-acorn season were hair samples, we suggest that hair traps should be technically feasible and suitable for areas with sparsely distributed populations.