Department of Biology, Universidad Autónoma de Madrid. C/ Darwin 2, Campus Universitario de Cantoblanco, 28049 Madrid, Spain,
Institute of Science and Environment, University of Saint Joseph, Macau, China.
Zoolog Sci. 2023 Aug;40(4):273-277. doi: 10.2108/zs230004.
While mobbing, individuals utter distinctive calls and perform visual threatening displays. Like any other antipredatory strategies, it involves some costs (time, energy, injuries, and even death). Therefore, mobbing would be expected to vary depending on the perceived magnitude of the predation risk. Moreover, harassment behavior can also serve as a demonstration of social status and to teach juveniles to recognize predators and related behaviors. Therefore, mobbing could also persist even when predation risk is particularly low. To test our hypotheses, we used tawny owl playbacks and a taxidermy mount to elicit the mobbing response in azure-winged magpies throughout the daylight period. To classify mobbing intensity, we created five categories depending on the proximity to the owl model at which the mobbing was performed. The results revealed that mobbing behavior in azure-winged magpies was more intense where predation risk was higher: in the most suitable habitat for the tawny owl, the forest, although considerable levels of mobbing were found in the dehesa and the ecotone, which indicate that mobbing has different purposes. However, we did not find statistically significant differences in mobbing intensity depending on the time of the day. We could not show a daily adjustment of antipredator response, but magpies modulated mobbing depending on the perceived risk linked to the habitat.
在群体攻击时，个体发出独特的叫声并展示视觉威胁。与任何其他防御策略一样，它涉及一些成本（时间、能量、受伤甚至死亡）。因此，群体攻击的程度应该会根据感知到的捕食风险的大小而有所不同。此外，骚扰行为还可以作为社会地位的展示，并教导幼鸟识别捕食者和相关行为。因此，即使捕食风险特别低，群体攻击也可能持续存在。为了验证我们的假设，我们在白天使用了茶隼的叫声和标本来激发蓝翅八色鸫的群体攻击反应。为了对群体攻击的强度进行分类，我们根据进行群体攻击时与猫头鹰模型的接近程度创建了五个类别。结果表明，在捕食风险较高的地方，蓝翅八色鸫的群体攻击行为更为激烈：在最适合茶隼生存的森林中，尽管在德氏松林和生态过渡区也发现了相当程度的群体攻击，但这表明群体攻击具有不同的目的。然而，我们没有发现群体攻击强度与一天中的时间之间存在统计学上的显著差异。我们无法证明这种针对捕食者的反应存在日常调整，但蓝翅八色鸫会根据与栖息地相关的感知风险来调节群体攻击。
