諸羅樹蛙群集展示行為之研究

Lekking Behavior in the Farmland Green Treefrog(Rhacophorus arvalis)

謝煒智(Wei-Chih Hsieh)

指導教授 ： 呂 光 洋 博士

國立臺灣師範大學/理學院/生命科學研究所/碩士(2003年)

摘要

諸羅樹蛙(Rhacophorus arvalis)屬於樹蛙科(Rhacophoridae)為臺灣特有種兩棲類，其配對系統屬於典型的群集展示系統(lek)。2003年4月至2004年6月間，研究者在雲林縣斗南鎮觀察記錄本種樹蛙的群集展示行為及日活動模式，並分析棲地的生態因子，以了解雄蛙對於展示場地選擇之偏好。
研究結果顯示，生殖季中展示場的位置相當固定。展示場每晚出現的雄蛙數目從0~38隻不等，受雨量影響極大。在展示場平均停留43.8天。雄蛙對展示場的忠誠度極高，不會在不同展示場之間遊走。生殖高峰﹙7，8月﹚前有大量雄蛙進入展示場，生殖季晚期則沒有新加入的個體。以核心估算法計算雄蛙生殖季在展示場的平面活動範圍，其25%活動範圍為10.6㎡，50%活動範圍為41.1㎡。
生殖季中雄蛙每天的活動模式大致上是呈現垂直的移動，對於棲地的利用可概分為二個部分，竹林的上層﹙4m以上﹚及中層﹙0.3m ~4m﹚，上層為樹蛙的休息區，是日間及不進行展示行為時所棲息的場所，中層為展示場所。展示場的位置和竹林底層的積水程度、光照度及竹叢的密度有顯著相關，和竹叢的高度無關。雄蛙的聚集現象可用Hotspot hypothesis解釋。

關鍵字

諸羅樹蛙 ； 群集展示行為 ； 活動模式 ； 核心估算法

並列摘要

Farmland green treefrog (Rhacophorus arvalis) belonging to the family Rhacophoridae is endemic to Taiwan. The mating system of Rhacophorus arvalis is lek. From April 2003 to June 2004 at Yunling in central Taiwan, I investigated the lekking behavior and daily activity pattern, and analyzed the ecological factors on habitat to understand the lek preference in male frogs.
During breeding seasons, the results showed that there were present consistent lekking sites on habitats. There were 0~38 males in the lek every night, and the number of males were affected by the amount of rainfall. The average day of the males in lek was 43.8. Males showed high lek fidelity and did not move between two leks. Before the reproductive peak (July-August), many males joined the lek, but during the late breeding seasons, no new individual was identified in the same lek. Based on the adaptive kernel method, the area of 25% male home range in the lek was 10.3m2 and the 50% area was 40.5m2.
Daily activity pattern of males displayed vertical movement during breeding seasons. The utility of habitat was characterized as two layers, the upper (> 4m) and middle (0.3m ~ 4m) layers of bamboos. The upper layer was the rest area, where frogs stayed in the daytime and had no lekking behavior, and the middle for lekking. The lek site in the study areas was significantly associated with the ground water level of bamboo fields, the lux, and the density of bamboos, relatively, but had no association with the height of bamboos. The male aggregation might be explained by the Hotspot hypothesis.

並列關鍵字

Rhacophorus arvalis ； Lekking Behavior ； activity pattern ； adaptive kernel method

參考文獻

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