A study of transition in turtle species composition in Japan: A case of Okayama Prefecture

2017 Fiscal Year Final Research Report

• Project/Area Number: 15K07233
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Ecology/Environment
• Research Institution: Okayama University of Science
• Principal Investigator: KAMEZAKI NAOKI 岡山理科大学, 生物地球学部, 教授 (50422366)
• Co-Investigator(Kenkyū-buntansha): 源 利文 神戸大学, 人間発達環境学研究科, 准教授 (50450656) ; 高橋 亮雄 岡山理科大学, 理学部, 准教授 (50452967) ; 鈴木 大 東海大学, 生物学部, 講師 (90647489)
• Project Period (FY): 2015-04-01 – 2018-03-31
• Keywords: カメ / 遷移 / 外来種 / 環境DNA

Outline of Final Research Achievements

A study was conducted to clarify the transition of the freshwater turtle phase in the Okayama plain. Analysis of the bones excavated from the ruins in addition to the literature and art materials, at least from the Middle Ages to the year 1900 was dominated by the Mauremys japonica, but it became clear that in 1990 the Mauremys reevesii was replaced. In this catch survey, 1267 M. reevesii(70.5%), 484 Trachemys scripta elegans (26.9%), 35 M. japonica (1.9%) etc were caught. Including the results of environmental DNA survey, the M. japonica fell sharply and proved to be on the verge of extinction. In addition, the number of T. s. elegans populations has been increasing mainly in rivers, and from the distribution characteristics it is considered that the T. s. elegans has invaded through the river from the sea.

Free Research Field

生態学