Transition of decapod crustacean fauna in Tokyo Bay based on the museum specimens and environmental change

2022 Fiscal Year Final Research Report

• Project/Area Number: 19K01146
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Review Section: Basic Section 03070:Museology-related
• Research Institution: Natural History Museum and Institute, Chiba
• Principal Investigator: Okuno Junji 千葉県立中央博物館, その他部局等, 研究員(移行) (60280749)
• Project Period (FY): 2019-04-01 – 2023-03-31
• Keywords: 自然史博物館 / 標本 / 横浜 / 高度経済成長 / 個体群絶滅 / 陸水

Outline of Final Research Achievements

In order to clarify the decapod crustacean fauna at the time of the old Tokyo Bay kept the favorable natural environment, the present study investigated the decapod specimens collected in Yokohama, the gateway to Japan during the Meiji era, based on the natural history museum collections in the United Kingdom, Germany and Austria. A total 52 species of 28 families of decapods were confirmed to have inhabited Yokohama in the Meiji era. These species were compared with the specimens newly collected in Yokohama, and the coastal environment at that time was verified on the basis of the old maps and photographs. The results suggest that after the period of rapid economic growth, the population of some species that prefer the seagrass beds and that of a part of coastal terrestrial species became extinct. On the other hand, numerous species were found to have maintained their populations in freshwater and offshore environments from the Meiji Era to the present days.

Free Research Field

博物館学

Academic Significance and Societal Importance of the Research Achievements

わが国の博物館では、環境の変遷を追跡するために動植物の標本を定期的に収集し、これを恒久的に保管するという考え方が定着していない。明治初頭、博物館とほぼ同時期にわが国に導入された動植物の分類学とそれに付随する標本の収集と保管は、東京帝国大学との結びつきが強かった。そのため、欧米では自然史博物館の中心的な活動であるにもかかわらず、自然史資料に関する位置付けは、博物館活動のフォーマットを検討する中から抜け落ちていた。今回、自然史博物館の甲殻類標本を調査することで、120年前の東京湾の動物相やそれらの生息する環境を再認識することができ、改めて博物館の自然史資料が持つ社会的意義を問い直す契機となる。