International cooperative research on migration mechanism and conservation of endangered sea turtles in theASEAN seas

海龟种类包括棱皮龟、绿色龟、赤海龟、玳瑁、橄榄棱纹龟、肯普橄榄棱纹龟和平背龟，分布于世界亚热带和热带地区，并从觅食地迁移到筑巢地。它们的数量减少，所有这些物种在世界上包括东南亚都面临灭绝。减少海龟数量的原因有很多。全球气候变化引起了海洋环境的变化，对海龟产生了影响。否则，人为的原因，例如沿海发展和捕鱼活动，现在也是严重的问题。本研究以“ASEAS海域绿色海龟的野生迁移机制分析研究”（KAKENHI，2002 - 2004）的研究成果为基础，进行了一些实验，以阐明幼海龟和幼海龟的迁移机制，并比较野生孵化场幼海龟和人工孵化场幼海龟的游泳能力。结果表明，仔稚鱼具有较好的游走能力，但随着年龄的增长，这种能力逐渐丧失。此外，野生幼海龟的潜水行为可能与人工饲养的幼海龟存在差异。

Sea turtle species including leatherback turtles, green turtles, loggerhead turtles, hawksbill turtles, olive ridley turtles, Kemp's olive ridley turtles and flatback turtle distribute subtropical areas and tropical areas in the world and migrate from feeding ground to nesting ground. The number of their population decreases and all these species face extinction in the world including the Southeast Asia. There are many reasons to decrease the number of the sea turtles. The global climate change caused the change of marine environment and affected the sea turtle. Otherwise, artificial reasons such as a coastal development and fishing activity are also serious matters now. Based on the result the former project, "Analytical study on the mechanism of wild migration of green turtles in the ASEAS sea areas" (KAKENHI, 2002 - 2004), this study performed some experiments to clarify a mechanism of migration of juvenile and young sea turtles and to compare the swimming ability between wild hatchery juveniles and artificial ones. Judging from the results, it is indicated that the hatchling juveniles have good ability to swim off but the ability is lost with their growth. Moreover, there may be difference in the diving behavior between the wild young sea turtles and the artificial rearing ones.