| Summary: | 碩士 === 國立嘉義大學 === 森林暨自然資源學系研究所 === 104 === Landuse change that cause habitat loss and degradation has been shown to be one of the main factors to affect biodiversity. The threat is especially severe for species such as amphibians that have low dispersal ability and high sensitivity to environment. In order to propose effective conservation measures, the information of species distribution and population size is needed. The farmland green tree frog (Rhacophorus arvalis) is an endemic amphibian of Taiwan. Its current distribution range is limited in Yunlin, Chiayi and Tainan areas. R. arvalis inhabits primarily in certain kind of farmland such as bamboo and orchard. In recent years, the conversion of agricultural landuse in Chiayi area raises concerns about it might cause the habitat loss to R. arvalis. The study aims to understand the current distribution and population size of R. arvalis in Chiayi area, and to evaluate the effect of landuse change on potential habitat of R. arvalis from 2006 to 2014. I investigated the distribution and population density using Audio Strip Transects and Visual Encounter Surveys in reproduction seasons of 2014 and 2015, then predicted the potential habitat of R. arvalis by the Maximum Entropy Model. At last, I compared changes of landuse and potential habitat of R. arvalis from 2006 to 2014. The results show that R. arvalis prefers the forest habitat, particularly bamboo fields, but avoids rice, pineapple fields and buildings. The predicted potential habitat is 32.4 % of the studied area of 2014/2015. The population size of farmland green tree frog in Chiayi area was estimated about 7,700. From 2006 to 2014, the predicted potential habitat decreased approximately 3.8 % and isolation of habitat patches increased. I suggest that a relatively small scale landuse classification can be used in the future to perform more precise prediction of potential habitat. In addition, there is a need to implement conservation measures such as expanding the habitat or establishment of stepping stones among habitat patches.
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