ベイト・ボール

映像外部リンク
	Fish bait ball in open water Blue Planet, BBC
	Bait Ball Feast The Great Feast, BBC
	Bluefin tuna eat bait ball National Geographic
	Shearwater attack! - Blue Planet BBC Wildlife
	Amazing bait balls & predatory fishermen BBC
	Marlin feeding on sardine ball YouTube

画像外部リンク
	Bait ball symphony
	Cooperative hunting by sailfish
	Bronze whalers charge a baitball - Nature's finest caught on camera BBC News, 21 October 2004.

ベイト・ボール（英:bait ball, baitball）は、魚類がつくる球形群。被捕食者が捕食者から身を守るためにつくる場合が多いが、群れをなすことで目立つため、捕食者に見つかりやすくなる。

ベイト・ボールを形成する被捕食魚

イワシ
- 直径10-20m
- 水深10m
- 形成時間10分超
アンチョビ

群れの形成

外洋性の魚類は海流に乗り移動し続けているため、海藻や珊瑚、岩影等のセーフティスポットを常に使用できる状況にない。食物連鎖上位の大きな魚であれば群れを作らずとも良いが、下位の小さな魚は単体では捕食者（魚類、ほ乳類、鳥類）への抵抗手段を持たないケースが多いため、生存戦略として群れを形成する場合がある。群れの形成により外敵に発見されやすくなるが、何百何千と群れの総数を増やすことで自らが生き残る確率は高くなる。バラバラに動くのではなく、互いの移動方向を察知することで1つの大きな生命体のようにふるまう。^[1] ^[2]^[3] ^[4]^[5]^[6]

ベイト・ボールは概して、捕食者が被捕食魚類より下位に存在する場合形成される。^[7]

過程

2001年, イルカ、マグロ、ミズナギドリの捕食行動を観察した Clua, Grosvalet の4段階分類^[8]：

準備段階（preparation phase）：イルカは被捕食魚の群れの周りを周回し、群れを小さくする。
強化段階（intensification phase）：ベイト・ボールはより集まり、周縁部の魚は海上の鳥、魚から捕食される
成熟段階（mature phase）：マグロの垂直捕食、イルカの離散、ベイト・ボールの集中
分散段階（dispersion phase）：マグロ、海鳥が離脱、部分的にイルカは残りのベイト・ボールを継続して捕食

捕食者

以下に捕食者および捕食方法を紹介する。

哺乳類

クジラ

海中のベイトボール下方から、開口して加速しながら上部のベイトボールを食べる（lunge feed）^[9] ^[10]。

ザトウクジラ

bubble net feeding 群れでベイト・ボール下方から気泡（bubble net^[11]）を放出、群れを小さくした上で垂直に捕食する（lunge feed） ^[12] ^[13] ^[14]^[15] 。

尾びれで海面を叩く スラッピング（lobtail)も観察される^[16] 。

ニタリクジラ^[17]^[18]

イルカ

浅瀬にベイト・ボールを追い込み、捕食する^[19] 気泡をベイト・ボールに向けて放出する^[20]。

魚類

メカジキ

高速で群れに当たり、被捕食魚を弱らせた後に引き返して捕食する^[21]。

オナガザメ

尾びれで被捕食魚を気絶させる^[22]。長い尾びれを使い、群れのまわりを回転することでベイト・ボールの直径を小さくし、捕食する^[22]。

シャチ

気泡、あるいは、体下面の白い部分を見せて被捕食魚（鮭、ニシン属など）をより小さな群れにし、尾びれで群れを叩いてから捕食する。

carousel feeding：ノルウェーで観測^[23]

ハナザメ

群れの下に位置し、海中で回転しながら下から上に垂直に向かい、開口して捕食する^[24]^[25]。

ジンベエザメ

クロトガリザメ

群れをつくり、被捕食魚を海面近くに追いあげた上で捕食する^[26] ^[27]。

鳥類

カツオドリ

海上30m(10フィート)の高さから降下し、最大時速86km(時速53マイル)で入水して捕食する。最大で34m(111フィート)まで潜り、空気の道筋をつくる。カツオドリには、顔と胸部の皮膚下に衝撃を緩衝する空気袋がある^[28]^[29]。

脚注

[脚注の使い方]

出典

^ Megurran, AE (1990) "The adaptive significance of schooling as an anti-predator defense in fish" Annales Zooligici Fennici, 27: 51-66.
^ Partridge BL (1982) "The structure and function of fish schools" Archived 2011年7月3日, at the Wayback Machine. Scientific American, 246(6) 114–123.
^ Magurran AE and Pitcher TJ (1987) "Provenance, shoal size and the sociobiology of predator-evasion behaviour in minnow shoals" Proc. R. Soc. Lond. B, 229(1257): 439-465. doi:10.1098/rspb.1987.000
^ Reynolds CW (1987) "Flocks, herds and schools: A distributed behavioral model" Computer Graphics, 21(4), 25–34. doi:10.1145/37401.37406
^ Parrish JK , Viscido SV and Grunbaumb D (2002) "Self-organized fish schools: An examination of emergent properties" Biol. Bull. 202: 296 –305.
^ Seifert DD (2010) Water Column: Finishing School Archived 2010年1月24日, at the Wayback Machine. November 2010, Dive Magazine UK.
^ Hamilton WD (1971) "Geometry for the selfish herd" Archived 2011年7月21日, at the Wayback Machine. Journal of Theoretical Biology 31: 295-311.
^ Clua and Grosvalet F (2001) "Mixed-species feeding aggregation of dolphins, large tunas and seabirds in the Azores" Aquatic Living Resources, 14(1): 11 - 18. doi:10.1016/S0990-7440(00)01097-4
^ Reeves RR, Stewart BS, Clapham PJ and Powell J A (2002) National Audubon Society Guide to Marine Mammals of the World Chanticleer Press. ISBN 9780375411410=.
^ Potvin J and Goldbogen JA (2009) "Passive versus active engulfment: verdict from trajectory simulations of lunge-feeding fin whales Balaenoptera physalus J. R. Soc. Interface, 6(40): 1005–1025. doi:10.1098/rsif.2008.0492
^ Bubble net feeding Archived 2011年9月3日, at the Wayback Machine. Alaska Whale Foundation. Retrieved 31 March 2011.
^ Hain JHW, Carter GR, Krau, SD, Mayo CA and Winn HE (1982) "Feeding behaviour of the humpback whale, Megaptera novaeangliae, in the Western North Atlantic". Fishery Bulletin, 80: 259–268.
^ Sharpe FA and Dill LM (1997) "The behavior of Pacific herring schools in response to artificial humpback whale bubbles" Canadian Journal of Zoology, Can J Zool, 75:725–730.
^ Acklin, Deb (2005年8月5日). “Crittercam Reveals Secrets of the Marine World”. National Geographic News 2007年11月1日閲覧。
^ Prepared by the Humpback Whale Recovery Team for the National Marine Fisheries Service, Silver Spring, Maryland (1991). Recovery Plan for the Humpback Whale (Megaptera novaeangliae). National Marine Fisheries Service. pp. 105
^ Weinrich MT, Schilling MR and Belt CR (1992) "Evidence for acquisition of a novel feeding behaviour: lobtail feeding in humpback whales, Megaptera novaeangliae" Animal Behaviour, 44: 1059–1072. doi:10.1016/S0003-3472(05)80318-5
^ Arnold PW, Birtles RA, Sobtzick S, Matthews M and Dunstan A (2005) "Gulping behaviour in rorqual whales: underwater observations and functional interpretation" Memoirs of the Queensland Museum, 51, 309–332
^ Goldbogen JA, Calambokidis J, Shadwick RE, Oleson EM, McDonald MA and Hildebrand J A (2006) "Kinematics of foraging dives and lunge-feeding in fin whales" Journal of Experimental Biology, 209, 1231–1244.
^ Coastal Stock(s) of Atlantic Bottlenose Dolphin: Status Review and Management Proceedings and Recommendations from a Workshop held in Beaufort, North Carolina, 13 September 1993 – 14 September 1993, http://www.nmfs.noaa.gov/pr/pdfs/species/coastalbottlenosestock.pdf, U.S. Department of Commerce, National Oceanic and Atmospheric Administration, National Marine Fisheries Service
^ Neumann D R and Orams MB (2003) "Feeding behaviours of short-beaked common dolphins, Delphinus delphis, in New Zealand". Aquatic Mammals, 29: 137–149.
^ Helfman GS, Collette BB and Facey DE (1997) The diversity of fishes Page 326, Wiley-Blackwell. ISBN 9780865422568.
^ ^a ^b Seitz, J.C. Pelagic Thresher. Florida Museum of Natural History. Retrieved on December 22, 2008.
^ http://rparticle.web-p.cisti.nrc.ca/rparticle/AbstractTemplateServlet?calyLang=eng&journal=cjz&volume=71&year=1993&issue=8&msno=z93-210^{[リンク切れ]}, 1993, Surface and underwater observations of cooperatively feeding killer whales
^ Compagno, L.J.V. (1984). Sharks of the World: An Annotated and Illustrated Catalogue of Shark Species Known to Date. Rome: Food and Agricultural Organization. pp. 466–468. ISBN 9251013845
^ “Carcharhinus brevipinna, Spinner Shark”. MarineBio.org. May 9, 2009閲覧。
^ Bonfil, R. (2008). “The Biology and Ecology of the Silky Shark, Carcharhinus falciformis”. In Camhi, M., Pikitch, E.K. and Babcock, E.A.. Sharks of the Open Ocean: Biology, Fisheries and Conservation. Blackwell Science. pp. 114–127. ISBN 0632059958
^ Martin, R.A. Open Ocean: Silky Shark. ReefQuest Centre for Shark Research. Retrieved on September 12, 2009.
^ Ropert-Coudert Y, Gremillet D, Ryan P, Kato A, Naito Y and Le Maho Y (2004) "Between air and water: the plunge dive of the Cape Gannet Morus capensis" Ibis , 146: 281–290.
^ Brierley AS and Fernandes PJ (2001) "Diving depths of Northern Gannets: acoustic observations of Sula bassana from an autonomous underwater vehicle". Auk, 118: 529–534.

参考文献

Burgess EA (2006) "Foraging ecology of common dolphins (Delphinus sp.) in the Hauraki Gulf, New Zealand" MSc thesis, Institute of Natural Resources, Massey University.
Dement J Species Spotlight: Atlantic Sailfish (Istiophorus albicans) littoralsociety.org. Retrieved 28 March 2011.
Leighton TG, PR White and Finfer DC (2009) "Hypotheses on the acoustics of whales, dolphins and porpoises in bubbly water" Proceedings of the Third International Conference on Underwater Acoustic Measurements, Technologies and Results.
Fetecau R (2010) "Collective behavior of biological aggregations in two dimensions: a nonlocal kinetic model" Mathematical Models and Methods in Applied Sciences, August 2010.
Marshall Cavendish Corporation (2004) Encyclopedia Of The Aquatic World Page 164, Marshall Cavendish. ISBN 9780761474180.
Mate BR (2010) "Sperm whales instrumented with ARGOS-GPS-TDR tags demonstrate coordinated dive behavior suggesting cooperative "bait-ball" feeding on Humbolt squids" Proceedings from the 2010 AGU Ocean Sciences Meeting.
Robinson KP, Stevick PT and MacLeod CD (2007) An integrated approach to non-lethal research on minke whales in European waters European Cetacean Society, Special publication series, No 47.
Robinson KP and Tetley MJ (2007) "Behavioural observations of foraging minke whales (Balaenoptera acutorostrata) in the outer Moray Firth, north-east Scotland" J. Mar. Biol. Ass. U.K., 87: 85–86. doi:10.1017/S0025315407054161
Sfakiotakisa M and Tsakiris DP (2007) "Neuromuscular control of reactive behaviors for undulatory robots" Neurocomputing, 70(10-12): 1907-1913.
Steiner L (1995) "Rough-toothed dolphin, Steno bredanensis: a new species record for the Azores, with some notes on behaviour" Life and Marine Sciences, 13A: 125–127.
Waters, Hannah (2010) Now in 3-D: The shape of krill and fish schools Scientific American. Invited commentary, 10 November 2010.

外部リンク

Queuing up for dinner: Dolphins enjoy sardine feeding frenzy Daily Mail, 15th July 2009. – this article has some spectacular images
Computer simulations of bait balls

[Megurran-1] Megurran, AE (1990) "The adaptive significance of schooling as an anti-predator defense in fish" Annales Zooligici Fennici, 27: 51-66.

[Partridge1982-2] Partridge BL (1982) "The structure and function of fish schools" Archived 2011年7月3日, at the Wayback Machine. Scientific American, 246(6) 114–123.

[3] Magurran AE and Pitcher TJ (1987) "Provenance, shoal size and the sociobiology of predator-evasion behaviour in minnow shoals" Proc. R. Soc. Lond. B, 229(1257): 439-465. doi:10.1098/rspb.1987.000

[4] Reynolds CW (1987) "Flocks, herds and schools: A distributed behavioral model" Computer Graphics, 21(4), 25–34. doi:10.1145/37401.37406

[5] Parrish JK , Viscido SV and Grunbaumb D (2002) "Self-organized fish schools: An examination of emergent properties" Biol. Bull. 202: 296 –305.

[Seifert-6] Seifert DD (2010) Water Column: Finishing School Archived 2010年1月24日, at the Wayback Machine. November 2010, Dive Magazine UK.

[7] Hamilton WD (1971) "Geometry for the selfish herd" Archived 2011年7月21日, at the Wayback Machine. Journal of Theoretical Biology 31: 295-311.

[8] Clua and Grosvalet F (2001) "Mixed-species feeding aggregation of dolphins, large tunas and seabirds in the Azores" Aquatic Living Resources, 14(1): 11 - 18. doi:10.1016/S0990-7440(00)01097-4

[9] Reeves RR, Stewart BS, Clapham PJ and Powell J A (2002) National Audubon Society Guide to Marine Mammals of the World Chanticleer Press. ISBN 9780375411410=.

[10] Potvin J and Goldbogen JA (2009) "Passive versus active engulfment: verdict from trajectory simulations of lunge-feeding fin whales Balaenoptera physalus J. R. Soc. Interface, 6(40): 1005–1025. doi:10.1098/rsif.2008.0492

[11] Bubble net feeding Archived 2011年9月3日, at the Wayback Machine. Alaska Whale Foundation. Retrieved 31 March 2011.

[12] Hain JHW, Carter GR, Krau, SD, Mayo CA and Winn HE (1982) "Feeding behaviour of the humpback whale, Megaptera novaeangliae, in the Western North Atlantic". Fishery Bulletin, 80: 259–268.

[13] Sharpe FA and Dill LM (1997) "The behavior of Pacific herring schools in response to artificial humpback whale bubbles" Canadian Journal of Zoology, Can J Zool, 75:725–730.

[14] Acklin, Deb (2005年8月5日). “Crittercam Reveals Secrets of the Marine World”. National Geographic News 2007年11月1日閲覧。

[Recplan91-15] Prepared by the Humpback Whale Recovery Team for the National Marine Fisheries Service, Silver Spring, Maryland (1991). Recovery Plan for the Humpback Whale (Megaptera novaeangliae). National Marine Fisheries Service. pp. 105

[16] Weinrich MT, Schilling MR and Belt CR (1992) "Evidence for acquisition of a novel feeding behaviour: lobtail feeding in humpback whales, Megaptera novaeangliae" Animal Behaviour, 44: 1059–1072. doi:10.1016/S0003-3472(05)80318-5

[17] Arnold PW, Birtles RA, Sobtzick S, Matthews M and Dunstan A (2005) "Gulping behaviour in rorqual whales: underwater observations and functional interpretation" Memoirs of the Queensland Museum, 51, 309–332

[18] Goldbogen JA, Calambokidis J, Shadwick RE, Oleson EM, McDonald MA and Hildebrand J A (2006) "Kinematics of foraging dives and lunge-feeding in fin whales" Journal of Experimental Biology, 209, 1231–1244.

[19] Coastal Stock(s) of Atlantic Bottlenose Dolphin: Status Review and Management Proceedings and Recommendations from a Workshop held in Beaufort, North Carolina, 13 September 1993 – 14 September 1993, http://www.nmfs.noaa.gov/pr/pdfs/species/coastalbottlenosestock.pdf, U.S. Department of Commerce, National Oceanic and Atmospheric Administration, National Marine Fisheries Service

[20] Neumann D R and Orams MB (2003) "Feeding behaviours of short-beaked common dolphins, Delphinus delphis, in New Zealand". Aquatic Mammals, 29: 137–149.

[21] Helfman GS, Collette BB and Facey DE (1997) The diversity of fishes Page 326, Wiley-Blackwell. ISBN 9780865422568.

[seitz-22] Seitz, J.C. Pelagic Thresher. Florida Museum of Natural History. Retrieved on December 22, 2008.

[23] ttp://rparticle.web-p.cisti.nrc.ca/rparticle/AbstractTemplateServlet?calyLang=eng&journal=cjz&volume=71&year=1993&issue=8&msno=z93-210^{[リンク切れ]}, 1993, Surface and underwater observations of cooperatively feeding killer whales

[compagno466-24] Compagno, L.J.V. (1984). Sharks of the World: An Annotated and Illustrated Catalogue of Shark Species Known to Date. Rome: Food and Agricultural Organization. pp. 466–468. ISBN 9251013845

[marinebio-25] “Carcharhinus brevipinna, Spinner Shark”. MarineBio.org. May 9, 2009閲覧。

[bonfil-26] Bonfil, R. (2008). “The Biology and Ecology of the Silky Shark, Carcharhinus falciformis”. In Camhi, M., Pikitch, E.K. and Babcock, E.A.. Sharks of the Open Ocean: Biology, Fisheries and Conservation. Blackwell Science. pp. 114–127. ISBN 0632059958

[martin-27] Martin, R.A. Open Ocean: Silky Shark. ReefQuest Centre for Shark Research. Retrieved on September 12, 2009.

[28] Ropert-Coudert Y, Gremillet D, Ryan P, Kato A, Naito Y and Le Maho Y (2004) "Between air and water: the plunge dive of the Cape Gannet Morus capensis" Ibis , 146: 281–290.

[29] Brierley AS and Fernandes PJ (2001) "Diving depths of Northern Gannets: acoustic observations of Sula bassana from an autonomous underwater vehicle". Auk, 118: 529–534.

[1]

[2]

[3]

[4]

[5]

[6]

[7]

[8]

[9]

[10]

[11]

[12]

[13]

[14]

[15]

[16]

[17]

[18]

[19]

[20]

[21]

[22]

[23]

[24]

[25]

[26]

[27]

[28]

[29]

映像外部リンク
Fish bait ball in open water Blue Planet, BBC
Bait Ball Feast The Great Feast, BBC
Bluefin tuna eat bait ball National Geographic
Shearwater attack! - Blue Planet BBC Wildlife
Amazing bait balls & predatory fishermen BBC
Marlin feeding on sardine ball YouTube

ベイト・ボールを形成する被捕食魚

群れの形成

過程

捕食者

哺乳類

魚類

鳥類

脚注

出典

関連項目

参考文献

外部リンク