Effects of masting on Asian black bear populations

• Project/Area Number: 16K21702
• Research Category: Grant-in-Aid for Young Scientists (B)
• Allocation Type: Multi-year Fund
• Research Field: Forest science; Cultural assets study and museology
• Research Institution: National Agriculture and Food Research Organization
• Principal Investigator: KOZAKAI Chinatsu 国立研究開発法人農業・食品産業技術総合研究機構, 中央農業研究センター, 任期付研究員 (90637670)
• Project Period (FY): 2016-04-01 – 2019-03-31
• Project Status: Completed (Fiscal Year 2018)
• Budget Amount: ¥4,030,000 (Direct Cost: ¥3,100,000、Indirect Cost: ¥930,000); Fiscal Year 2018: ¥780,000 (Direct Cost: ¥600,000、Indirect Cost: ¥180,000); Fiscal Year 2017: ¥650,000 (Direct Cost: ¥500,000、Indirect Cost: ¥150,000); Fiscal Year 2016: ¥2,600,000 (Direct Cost: ¥2,000,000、Indirect Cost: ¥600,000)
• Keywords: ツキノワグマ / マスティング / 堅果 / 豊凶 / 繁殖成功 / 個体群動態 / 頭骨標本 / 育児成功 / 繁殖 / 豊凶周期 / 成長動態 / 博物館資料 / 頭骨

Outline of Final Research Achievements

We investigated relationship between hard mast productivity and population dynamics of Asian black bears. We found high site fidelity over the years from the denning to summer season, and there was spatial proximity among related females. Female bears returned to sites near their primary range before den entry. This suggested that female bears could gain benefits on reproductive success from settling in familiar areas (in turn matrilineal site fidelity during spring, summer, and the denning season). In addition, we found reproductive success (parturition and lactation) in female bears decreases cementum annulus width of tooth, which appears to be a useful index of past reproductive history.

Academic Significance and Societal Importance of the Research Achievements

2000年代に入り気候変動に伴うと考えられる堅果類の豊凶の周期パターンの変化が観測されている中、堅果類の豊凶とツキノワグマ等の大型哺乳類の個体群動態との関係を正しく理解した上で、農作物被害や出没対策を行わなければならない。本研究はこれまで難しかったツキノワグマの繁殖履歴の推定手法を確立するなど、今後のクマ類の科学的な保護管理に大きく貢献する成果を得た。

Research Products

• [Journal Article] Does hard mast production affect patterns of cementum annuli formation in premolar teeth of Asian black bears (Ursus thibetanus)? (2019)
  • Author(s): Tochigi Kahoko、Aoki Yukino、Maruyama Tetsuya、Yamazaki Koji、Kozakai Chinatsu、Naganuma Tomoko、Inagaki Akino、Masaki Takashi、Koike Shinsuke
  • Journal Title: PLOS ONE Volume: 14 Issue: 2 Pages: e0211561-e0211561
  • DOI: 10.1371/journal.pone.0211561
  • Peer Reviewed / Open Access
• [Journal Article] Reproductive Histories of Asian Black Bears Can be Determined by Cementum Annuli Width (2018)
  • Author(s): Tochigi Kahoko、Tamatani Hiroo、Kozakai Chinatsu、Inagaki Akino、Naganuma Tomoko、Myojo Hiroaki、Yamazaki Koji、Koike Shinsuke
  • Journal Title: Mammal Study Volume: 43 Issue: 4 Pages: 261-261
  • DOI: 10.3106/ms2018-0016
  • NAID: 40021760746
  • Peer Reviewed
• [Journal Article] Influence of Food Availability on Matrilineal Site Fidelity of Female Asian Black Bears (2017)
  • Author(s): Kozakai Chinatsu、Nemoto Yui、Nakajima Ami、Koike Shinsuke、Ohnishi Naoki、Yamazaki Koji
  • Journal Title: Mammal Study Volume: 42 Issue: 4 Pages: 219-230
  • DOI: 10.3106/041.042.0404
  • NAID: 210000181032
  • Peer Reviewed
• [Presentation] Impact of beechnut masting on reproductive success of Asian black bear (2019)
  • Author(s): Kahoko Tochigi, Kiyoshi Yamauchi, Shigekazu Kurakake, Chinatsu Kozakai, Koji Yamazaki, Tomoko Naganuma, Shinsuke Koike
  • Organizer: 日本生態学会第66回全国大会
• [Presentation] ツキノワグマの行動とブナ科堅果類の豊凶との関係解明／現場の実情に即した保護管理に向けて2018年度（日本哺乳類学会奨励賞受賞講演） (2018)
  • Author(s): 小坂井千夏
  • Organizer: 2018年度日本哺乳類学会
  • Invited
• [Presentation] ツキノワグマの歯の年輪幅への繁殖履歴の反映の解明 (2018)
  • Author(s): 栃木香帆子、玉谷宏夫、小坂井千夏、稲垣亜希乃、長沼知子、名生啓晃、山﨑晃司、小池伸介
  • Organizer: 2018年度日本哺乳類学会