首次迁徙雀形目鸟类的多模态感觉操控

文献信息

中文摘要

背景： 迁徙过程中导航线索如何整合仍知之甚少，尤其是鸟类首次迁徙期间。为检验首次迁徙鸟类导航受多感觉系统（来自磁性颗粒的地磁地图信息和嗅觉线索）影响的假说，我们对正在开展首次秋季迁徙的普通红尾鸲 Phoenicurus phoenicurus 和黑顶林莺 Sylvia atricapilla 进行了实验性操控。方法：我们给予高强度磁脉冲、硫酸锌嗅觉缺失处理或两者兼施。利用自动无线电遥测在自然环境中确定迁徙出发方向。我们预测，如果鸟类以冗余或层级方式使用这些感觉系统，单一处理不会改变其迁徙行为；然而，如果鸟类同时依赖多模态感觉线索进行导航，则两种感觉的破坏将导致错误或改变的迁徙定向。结果：仅接受磁脉冲处理的鸟样本以与对照组相当的季节性适宜方向出发。然而，这种标准定向的集中度显著高于嗅觉缺失样本，提示嗅觉缺失破坏了自由飞行雀形目鸟类首次迁徙中的正常迁徙定向飞行（可能还有向量导航）。对嗅觉缺失的反应令人惊讶，因为迄今为止仅发现嗅觉参与有经验鸟类在后续迁徙中的导航。此外，同时接受磁处理和嗅觉处理的样本定向与其他组不同。结论：尽管样本量较小，本研究强调景观水平的迁徙行为和策略可能对于解释迁徙动物线索使用研究具有根本重要性。

英文摘要

How navigational cues are integrated during migration is still poorly understood, particularly in birds during their first migration. To test the hypothesis that first-year avian navigation is informed by multiple sensory systems (geomagnetic map information from magnetic particles and olfactory cues), we experimentally manipulated common redstarts Phoenicurus phoenicurus and blackcaps Sylvia atricapilla, undertaking their first autumn migration. We administered either a high-intensity magnetic pulse, or zinc sulphate anosmic treatment, or both. Migratory departure directions were determined in the natural environment using automated radiotelemetry. We predicted that if birds used these sensory systems with redundancy or in a hierarchical manner, single treatments would not change their migratory behaviour, however if birds simultaneously rely on multimodal sensory cues for navigation, the disruption of both senses will lead to incorrect or altered migratory orientation. The sample of birds which received the magnetic pulse only treatment departed in a seasonally appropriate direction equivalent to controls. This standard orientation was however significantly higher in concentration than the anosmic sample, suggesting anosmia disrupts normal migratory directed flight (and possibly vector navigation) in free-flying passerines on their first migration. The response to anosmia is surprising as olfaction has so far only been found to be involved in navigation of experienced birds during subsequent migrations. Furthermore, the sample treated with both magnetic and olfactory treatment oriented differently to other groups. Despite the low sample sizes, this study highlights that landscape level migratory behaviours and strategies are likely fundamental to the interpretation of studies on cue use in migratory animals.