Brönmark C, Malmqvist B, Otto C
Department of Animal Ecology, University of Lund, Ecology Building, S-223 62, Lund, Sweden.
Oecologia. 1984 Feb;61(2):189-191. doi: 10.1007/BF00396758.
The risk of a Velia caprai (Heteroptera: Veliidae) individual to fall victim to brown trout (Salmo trutta) was demonstrated experimentally to be markedly lower when several bugs were simultaneously exposed to the trout. V. caprai was found distasteful to brown trout, and a high proportion was ejected alive after being captured. We suggest that school formation in V. caprai lowers the risk of predation because frequent predator-prey encounters may assist in retention of the avoidance learned by the predator. Individual behavioural responses to attacks were variable and the frequency of expansion skating and thanatosis was temperature dependent. Thanatosis postures were either symmetric with the legs pressed to the body or irregular.
通过实验证明，当同时将几只维氏伊蚊（半翅目：宽肩蝽科）个体暴露于褐鳟（Salmo trutta）面前时，其成为褐鳟猎物的风险显著降低。人们发现褐鳟不喜欢维氏伊蚊，并且很大一部分维氏伊蚊在被捕获后仍能活着被吐出。我们认为，维氏伊蚊形成群体可降低被捕食的风险，因为频繁的捕食者 - 猎物相遇可能有助于捕食者记住所学到的回避行为。个体对攻击的行为反应各不相同，扩展滑行和假死的频率取决于温度。假死姿势要么是腿部紧贴身体的对称姿势，要么是不规则姿势。
