Video S2. Temporary division of roles in a group of the false cleanerfish Aspidontus taeniatus raiding a nest of the three-spot dascyllus Dascyllus trimaculatus.

(90.8MB, 00:01:48)
撮影日：2019/09/14
撮影場所：瀬底島

佐藤　初
(Hajime Sato)
2024/05/13登録

種類：ニセクロスジギンポ, Aspidontus taeniatus
キーワード：cooperation division of roles egg eating false cleanerfish group hunting

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動物界 >脊索動物門 >硬骨魚綱 >スズキ目 >イソギンポ科 >クロスジギンポ属 >

3個体のニセクロスジギンポがミツボシクロスズメダイ（以下，ミツボシ）の巣を狙っている（0:00～0:13）．匍匐前進で巣の近くまで接近し，窪みに身を隠す（0:13～0:23）．先頭個体がミツボシを監視するウォッチャー（Watcher：監察役）となり，他の2個体が身を隠すハイダー（Hider：潜伏役）となる（0:23～0:29）．ミツボシがウォッチャーに気が付き攻撃する（0:29～0:30）．その隙にハイダーが巣へ突入する（0:30～0:31）．しかし，戻ってきたミツボシに攻撃され失敗する（0:31～0:32）．再度スローモーションで再生（0:33～0:48）．一度，巣を離れ，再び同じミツボシの巣を狙う．今度は同じ岩のやや後ろのポジションに隠れ機会を伺う（0:48～1:01）．ミツボシがハイダーを攻撃すると同時に，ウォッチャーと別のハイダーが巣へ突入する（1:01～1:08）．引き続き，追いかけられたハイダーも巣へ突入する（1:08～1:13）．ミツボシの両親ペアがニセクロスジギンポに噛みついて激しく巣を防衛する（1:13～1:21）．しかし，強引にも巣への突入を繰り返して卵の捕食に成功する（1:21～1:45）．

Below is the abstract from the article containing this video:

Division of roles was observed during group hunting by the false cleanerfish, Aspidontus taeniatus (Blenniidae), when they raid the nests of the damselfish (Pomacentridae) and eat their guarded eggs. In this paper, we provide the first description of the collaborative group egg-eating behavior by the false cleanerfish. When raiding the nests of the three-spot dascyllus, Dascyllus trimaculatus, whose eggs are guarded by parents, the false cleanerfish divided roles as follows: “decoy” or “watcher” to draw attention and attract attacks from the parents, and “hider” or “intruder” to avoid detection by the parents and invade the nest. The potential differential costs associated with each role are unique among examples of group hunting strategies in fishes. However, once any individual in the group successfully invaded the nest, all individuals quickly achieved successful predation of the eggs and gained immediate shared benefit. We propose that the group egg-eating behavior of the false cleanerfish not only reinforces the evidence that fish can collaborate with other individuals but also suggests the hypothesis that collaborative hunting can evolve through mutualism even in fishes. Digital video images related to the article are available at http://www.momo-p.com/showdetail-e.php?movieid=momo240411at01a, and http://www.momo-p.com/ showdetail-e.php?movieid=momo240411at02a.

Hajime Sato, Yoichi Sakai, and Tetsuo Kuwamura (2024). Temporary division of roles in group hunting for fish eggs by a coral reef fish. J. Ethol. 10.1007/s10164-024-00812-w