A study on the impact from exotic Asiatic painted frog (Kaloula pulchra) in Taiwan and its origin

• Main Authors: Sigmund K. P. Liang, 梁高賓
• Other Authors: Lue Kuang-Yang
• Format: Others
• Language: zh-TW
• Published: 2005
• Online Access: http://ndltd.ncl.edu.tw/handle/82031633981239467303

碩士 === 國立臺灣師範大學 === 生命科學研究所 === 93 === Asiatic painted frog, a medium size one is a newly recorded species in Taiwan. It belongs to family Microhylidae, genus Kaloula, Kaloula pulchra. Asiatic painted frog was suspected to be introduced with imported timbers in last couple years. In order to understand the ecological impacts from Kaloula pulchra on local frog fauna, we conducted a study in Fong Shan reservoir. We used Martof toe clipping method to mark each individual encountered in the wild. Population size in Fong Shan reservoir was estimated by using Jolly-Seber mark and recapture method. The population age structure was constructed by skeletochronology. Meanwhile, home ranges of several individuals were calculated. Niche breath of microhabitat resource and food items in the stomach were calculated by Hurlbert’s niche breath measurement. We also estimated niche overlap between Asiatic painted frog and other sympatric species. PCR and other molecular techniques were applied, and mtDNA were sequenced, we compared the genetic structure of individuals from Taiwan and Hong Kong. The estimated population size is about 259 individuals in Fong Shan reservoir, and captured individuals mainly are the breeding ones. The appearance of Kaloula during the night is significantly related to precipitation (R=0.7841, P<0.00004). Besides precipitation, the other factor affects the appearance of Kaloula is the low temperature in winter. In microhabitat resources, the niche breath of Kaloula is 0.67±0.12. The competition between Kaloula pulchra and Bufo melanostictus is prominent, Horn’s index is 0.98. We suspected that invaded Kaloula pulchra may cause species composition shift in a local frog fauna. Kaloula pulchra in Taiwan showed only one haplotype. While more than one haplotypes were discovered from Hong Kong frogs. This indicated that they invaded to Taiwan from a single source recently all descendants may come from a single female frog only. To find out the area where it came from, more specimens from other countries will be needed.