Study on the maintenance system and conservation of the island ecosystem of Iriomote National Park

本计画旨在对日本琉球群岛西表岛的岛屿生态系统进行全面调查，并探讨岛屿生态系统的整体管理程序。本研究以西表岛生态系统的关键物种西表猫为研究对象，对西表岛低营养级的动物群和植物群进行了分析，并对西表岛生境条件进行了评价，包括人为因素的影响。并分析了生物和非生物因素的影响。分析了西表岛猫科动物生态、两栖类丰富度和多样性、土地开发和交通事故发生等3个与西表岛猫科动物生态密切相关的因素。特别是对爬行动物和植物种类以及东南亚样品进行了详细的分析。4.调查了被认为对西表岛动物区系有强烈影响的两种入侵物种野猫和海蟾蜍的情况和影响，在此基础上讨论了濒危西表猫和西表岛生态系统的保护问题。本项目阐明了西表猫的现状、影响因素及该地区陆生动物群和植物群的特征。今后还需要进行详细分析调查，以了解西表岛生态系统。

This project aims to conduct the inclusive surveys and to discuss the total management procedure of island ecosystem of the Iriomote Island, in Ryukyu Archipelago, Japan. The study focused first on the Iriomote cat as the key species of this island ecosystem, secondly on the fauna and flora at the lower trophic level in community and environmental factors, and thirdly on the assessment of habitat condition including the artificial effects.1.We obtained the field data on the ecology of the Iriomote cat, especially home range, habitat utilization and movement pattern, partly using the GIS data, and analyzed the affecting biological and non-biological factors. Furthermore, we compared the results with those of the Tsushima leopard cat, which was also the insular species of wild felid.2.We analyzed the three factors closely relating to the ecology of Iriomote cats, abundance and diversity of Amphibia, land development and occurrence of traffic accidents.3.Taxonomical and biogeographical surveys were conducted on fauna and flora of this island. Especially, detailed analysis were done on reptiles and plant species together with South-eastern Asia samples.4.We conducted the situation and effects by two invasive species those were considered to have a strong impact on fauna of this island, feral cat and marine toad.Based on these results, we discussed the conservation of the endangered Iriomote cat and ecosystem of Iriomote Island. The situation and affecting factors of Iriomote cats and characteristics of terrestrial fauna and flora of this area were clarified in this project. Future surveys on the detailed analysis should be needed to understand the Iriomote ecosystem.