An Explanation of Migration Routes of Little Terns breeding in Okinawa

2018 Fiscal Year Final Research Report

• Project/Area Number: 15K06935
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Conservation of biological resources
• Research Institution: Uekusa Gakuen University
• Principal Investigator: HAYAKAWA MASAHARU 植草学園大学, 発達教育学部, 准教授 (60710928)
• Research Collaborator: FUJII takashi ; KITAMURA wataru ; MUROFUSHI alexander ryoh ; KANAZAWA satoshi ; MORIYAMA akihiko ; SUZUKI mieko ; MATHUBARA kazumi
• Project Period (FY): 2015-10-21 – 2019-03-31
• Keywords: コアジサシ / 渡り / GPS / 沖縄 / 台湾 / 中国 / mtDNA

Outline of Final Research Achievements

Little terns breeding in East Japan migrate to between Southeast Asia and the southeastern Australia, and Little terns breeding in Taiwan migrate to the northwestern Australia.
I tried to investigate where Little terns bred in Okinawa geographically near Taiwan migrated, using GPSs. However, I couldn't collect GPSs. From the data by the geo-locater which I carried out as a precedent study, it turned out that Little terns wintered in the northeastern Australia.
In addition, as a result of mtDNA investigation, it was revealed that "the group breeding in East Japan" and "the group breeding in Okinawa" were divided into the group of the different gene constitution, but the possibility that both groups interchanged was suggested.

Free Research Field

保全生態学

Academic Significance and Societal Importance of the Research Achievements

絶滅危惧種のコアジサシは渡り鳥であることから、保護のためには繁殖地・越冬地・中継地をセットにした保全が必要である。さらに、コアジサシの遺伝的な多様性を維持するためには、種としての保護だけでなく、個体群レベルでの保護が必要と考えられる。今回の研究により沖縄で繁殖する個体群は、東日本で繁殖する個体群と異なる可能性が高くなったので、沖縄の繁殖地の保全の重要性が明らかになったと考えられる。この先移動経路が明らかになっていくことで、保全すべき越冬地や中継地が明らかになっていくものと考えられる。