Damini Silvia, Blum Christian R, Sumasgutner Petra, Bugnyar Thomas
Department of Behavioral & Cognitive Biology, Faculty of Life Sciences, University of Vienna, Vienna, Austria.
Konrad Lorenz Research Center for Behavior and Cognition, Core Facility, Faculty of Life Sciences, University of Vienna, Vienna, Austria.
Anim Cogn. 2025 Jul 3;28(1):55. doi: 10.1007/s10071-025-01976-9.
The ability to respond appropriately to predators is essential for survival. Because response options vary with predation context, anti-predator behavior is often flexible, context dependent and shaped by learning. Corvids engage in predator mobbing, which contains a vocal component (scolding) and predator-directed behaviors (approaches, attacks). Individuals typically gang up for mobbing and pass on information about predators; yet their expression of antipredator behavior is influenced by factors such as social status, age, and rearing conditions. Here we investigated the development of antipredator behavior in ravens, specifically the onset of mobbing and the extent to which these responses are affected by parental agitation. We exposed 12 captive families to a potentially dangerous human (DH) at two stages of offspring development: shortly after fledging and near independence. We tested the hypotheses that (i) parents are more protective when the offspring are young and that (ii) offspring show more predator-directed behaviors with increasing age. We found that (i) adults mobbed significantly more during the early test period and (ii) offspring were less likely to ignore the DH and showed increased engagement during the late test period. These findings suggest that parental anti-predator investment diminishes as offspring develop greater motoric and cognitive abilities. This reduced investment may encourage offspring to independently assess and respond to threats. Yet, they hardly engage in mobbing while they are with their parents. Future studies may clarify if the increase in offsprings' interindividual variance in both mobbing components are indicative for the emergence of individuality.
对捕食者做出适当反应的能力对生存至关重要。由于应对方式会因捕食情境而异，反捕食行为通常具有灵活性、情境依赖性且受学习影响。鸦科鸟类会进行捕食者围攻，其中包括一个发声成分（责骂）和针对捕食者的行为（靠近、攻击）。个体通常会成群结队地进行围攻并传递有关捕食者的信息；然而它们的反捕食行为表现会受到社会地位、年龄和饲养条件等因素的影响。在这里，我们研究了渡鸦反捕食行为的发展，特别是围攻行为的开始以及这些反应受亲代激动影响的程度。我们在后代发育的两个阶段让12个圈养家庭接触一个潜在危险的人类（DH）：刚 fledging 后不久和接近独立时。我们检验了以下假设：（i）后代年幼时父母更具保护欲，以及（ii）后代随着年龄增长会表现出更多针对捕食者的行为。我们发现：（i）在早期测试阶段成年个体围攻行为显著更多，以及（ii）后代在后期测试阶段更不太可能忽视DH且参与度增加。这些发现表明，随着后代发展出更强的运动和认知能力，亲代的反捕食投入会减少。这种减少的投入可能会鼓励后代独立评估和应对威胁。然而，它们在与父母在一起时几乎不参与围攻。未来的研究可能会阐明后代在两种围攻成分上个体间差异的增加是否表明个性的出现。
