The characteristic inking behaviour of cephalopods is a secondary defence mechanism that helps them to escape predation. However, although it has been postulated that ink creates a decoy by disrupting the visual information received by the predator, the underlying mechanisms by which ink helps squid to escape from predators remain unknown. Therefore, we observed the inking behaviour of the Japanese pygmy squid (Idiosepius paradoxus). Field observations showed the squid intermittently and linearly ejected ink while rapidly swimming backwards in response to a predator and also changed their bodies to a light colour. This behaviour was then followed by a sudden and sharp change in swimming direction or sometimes a sudden break from swimming with a concurrent change in body colour to black. We also recorded the escape behaviour with inking under captive conditions in response to predatory sculpins, which allowed the successful escape from a predatory attack. Furthermore, the greater the number of ink ejections, the higher the probability that the sculpins would initiate a predatory attack on the ink rather than the squid. Together, these results suggest that squid inking behaviour exhibits a substantial decoy effect on predators and is associated with a series of complex, spatio-temporally regulated behaviours. Digital video images related to the article are available at http://www.momo-p.com/showdetail-e.php?movieid=momo200107ip01a, http://www.momo-p.com/showdetail-e.php?movieid=momo200107ip03a, and http://www.momo-p.com/showdetail-e.php?movieid=momo200107ip04a.

中文翻译：

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精心设计的行为序列加强了墨在对鱿鱼进行掠夺性攻击时的诱饵效果

头足类动物特有的着墨行为是一种辅助防御机制，可帮助它们逃脱捕食。然而，虽然假设墨水通过破坏捕食者接收到的视觉信息来制造诱饵，但墨水帮助鱿鱼逃离捕食者的潜在机制仍然未知。因此，我们观察了日本侏儒鱿鱼（Idiosepius paradoxus）的着墨行为。实地观察显示，鱿鱼间歇性地、线性地喷射墨水，同时快速向后游动以响应捕食者，并将它们的身体变成浅色。这种行为随后是游泳方向的突然急剧变化，或者有时突然停止游泳，同时身体颜色变为黑色。我们还记录了在圈养条件下对掠食性杜松鱼的反应，用墨水来逃避行为，这使得成功逃脱掠夺性攻击。此外，墨水喷射的次数越多，杜鹃花对墨水而不是鱿鱼发起掠夺性攻击的可能性就越大。总之，这些结果表明，鱿鱼上墨行为对捕食者表现出显着的诱饵效应，并且与一系列复杂的、时空调节的行为有关。与文章相关的数字视频图像可在 http://www.momo-p.com/showdetail-e.php?movieid=momo200107ip01a、http://www.momo-p.com/showdetail-e.php? movieid=momo200107ip03a 和 http://www.momo-p.com/showdetail-e.php?movieid=momo200107ip04a。这使得成功逃脱掠夺性攻击。此外，墨水喷射的次数越多，杜鹃花对墨水而不是鱿鱼发起掠夺性攻击的可能性就越大。总之，这些结果表明，鱿鱼上墨行为对捕食者表现出显着的诱饵效应，并且与一系列复杂的、时空调节的行为有关。与文章相关的数字视频图像可在 http://www.momo-p.com/showdetail-e.php?movieid=momo200107ip01a、http://www.momo-p.com/showdetail-e.php? movieid=momo200107ip03a 和 http://www.momo-p.com/showdetail-e.php?movieid=momo200107ip04a。这使得成功逃脱掠夺性攻击。此外，墨水喷射的次数越多，杜鹃花对墨水而不是鱿鱼发起掠夺性攻击的可能性就越大。总之，这些结果表明，鱿鱼上墨行为对捕食者表现出显着的诱饵作用，并且与一系列复杂的、时空调节的行为有关。与文章相关的数字视频图像可在 http://www.momo-p.com/showdetail-e.php?movieid=momo200107ip01a、http://www.momo-p.com/showdetail-e.php? movieid=momo200107ip03a 和 http://www.momo-p.com/showdetail-e.php?movieid=momo200107ip04a。杜鹃花对墨水而不是鱿鱼发起掠夺性攻击的可能性就越大。总之，这些结果表明，鱿鱼上墨行为对捕食者表现出显着的诱饵效应，并且与一系列复杂的、时空调节的行为有关。与文章相关的数字视频图像可在 http://www.momo-p.com/showdetail-e.php?movieid=momo200107ip01a、http://www.momo-p.com/showdetail-e.php? movieid=momo200107ip03a 和 http://www.momo-p.com/showdetail-e.php?movieid=momo200107ip04a。杜鹃花对墨水而不是鱿鱼发起掠夺性攻击的可能性就越大。总之，这些结果表明，鱿鱼上墨行为对捕食者表现出显着的诱饵作用，并且与一系列复杂的、时空调节的行为有关。与文章相关的数字视频图像可在 http://www.momo-p.com/showdetail-e.php?movieid=momo200107ip01a、http://www.momo-p.com/showdetail-e.php? movieid=momo200107ip03a 和 http://www.momo-p.com/showdetail-e.php?movieid=momo200107ip04a。