Data from: A test for repertoire matching in eastern song sparrows

Repertoire matching occurs when one songbird replies to another with a song type that the two birds share. Repertoire matching has previously been demonstrated to occur at well above chance levels in a western population of song sparrows, where it is hypothesized to serve as a low level threat in a hierarchy of aggressive signals. Here we test for repertoire matching in an eastern population of song sparrows. Previous work indicates that this eastern population differs from the western one in having lower levels of song sharing between neighboring males and in showing no association between song sharing and territory tenure. Here we confirm that males in this eastern population on average share few whole songs with their neighbors. The eastern males are familiar with their neighbors’ repertoires, as evidenced by a stronger singing response to stranger song than to neighbor song. Males in the eastern population did not repertoire match: when played an unshared song type from a specific neighbor, they did not reply with a song type shared with that neighbor more often than expected by chance or more often than in response to playback of a control song (an unshared stranger song). The results thus demonstrate a qualitative difference in vocal signaling strategies between two populations of the same species.

曲目匹配（repertoire matching）指一只鸣禽以双方共有的鸣唱类型回应另一只鸣禽的行为。既往研究已证实，西部歌带鹀（song sparrows）种群中曲目匹配的发生概率显著高于随机水平，且该行为被假设为攻击性信号层级中的低烈度威胁手段。本研究针对东部歌带鹀种群开展曲目匹配检测。既往研究表明，该东部种群与西部种群存在两方面差异：其一，相邻雄鸟间的鸣唱共享程度更低；其二，鸣唱共享与领地保有期无显著关联。本研究证实，该东部种群的雄鸟平均仅与邻居共享少量完整鸣唱。东部雄鸟能够识别邻居的鸣唱曲目，具体表现为对陌生鸣唱的鸣唱反应强度显著高于对邻居鸣唱的反应。东部种群的雄鸟未表现出曲目匹配行为：当播放来自特定邻居的未共享鸣唱类型时，它们并未以高于随机概率的频率，亦未比对照鸣唱（陌生未共享鸣唱）回放时更频繁地使用与该邻居共享的鸣唱类型进行回应。综上，本研究结果表明，同一物种的两个种群在鸣唱信号策略上存在质的差异。