Can large urban woodlands be a core habitat?

2020 Fiscal Year Final Research Report

• Project/Area Number: 17K08186
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Environmental agriculture(including landscape science)
• Research Institution: The Open University of Japan
• Principal Investigator: Katoh Kazuhiro 放送大学, 教養学部, 教授 (60242161)
• Project Period (FY): 2017-04-01 – 2021-03-31
• Keywords: 都市緑地 / 鳥類 / 移動 / エコロジカルネットワーク / 都市忌避種 / 緑道 / 生物多様性

Outline of Final Research Achievements

1) In the residential areas outside the studied urban woodlands, the abundance of urban-avoider woodland species decreased with the distance from the nearest woodland. Few individuals of urban-avoider woodland species were observed in the areas 250 m or more apart from the nearest woodland. 2) In the case of urban-adapter species such as Brown-eared Bulbul, some individuals distributed in the residential areas about 1 km or more apart from the nearest woodland. 3) Bird individuals recorded in the residential areas around the studied woodlands tended to move more easily in areas with less vegetation cover and stay there in areas with more vegetation cover. 4) Land use in the adjacent part of the woodland may influence the movement of bird individuals across the woodland boundaries. High artificial structures, such as elevated highways, may reduce the movement of avian individuals, except some urban birds such as Jungle Crows and Rock Doves.

Free Research Field

ランドスケープ科学

Academic Significance and Societal Importance of the Research Achievements

現在、都市の生物多様性を向上させるための方策として、既存の生物生息場所を移動路となる緑道や河川、あるいは移動の中継点となる小規模な生息場所で連結させる、エコロジカルネットワークの構築が検討されている。その際、鳥類の移動可能な範囲として500ｍが目安とされることがあるが、本研究の結果は、都市化の影響を受けやすい種に関してはより短い距離を基準として考える必要があることを示している。人為的な構造物が鳥類の移動の妨げになる可能性も明らかとなった。これらの知見は、実効性のあるエコロジカルネットワークの構築に寄与すると期待できる。