Data from: Learning to cope: vocal adjustment to urban noise is correlated with prior experience in black-capped chickadees

Urban noise can interfere with avian communication through masking, but birds can reduce this interference by altering their vocalizations. Although several experimental studies indicate that birds can rapidly change their vocalizations in response to sudden increases in ambient noise, none have investigated whether this is a learned response that depends on previous exposure. Black-capped chickadees (Poecile atricapillus) change the frequency of their songs in response to both fluctuating traffic noise and experimental noise. We investigated whether these responses to fluctuating noise depend on familiarity with noise. We confirmed that males in noisy areas sang higher-frequency songs than those in quiet areas, but found that only males in already-noisy territories shifted songs upwards in immediate response to experimental noise. Unexpectedly, males in more quiet territories shifted songs downwards in response to experimental noise. These results suggest that chickadees may require prior experience with fluctuating noise to adjust vocalizations in such a way as to minimize masking. Thus, learning to cope may be an important part of adjusting to acoustic life in the city.城市噪音可通过掩蔽效应（masking）干扰鸟类的通讯行为，而鸟类可通过调整鸣声以降低此类干扰。尽管多项实验研究表明，鸟类可随环境噪音的骤然升高而快速调整鸣声，但目前尚无研究探究此类响应是否属于依赖过往噪音暴露经历的习得性反应。黑头山雀（Poecile atricapillus）会针对波动的交通噪音与实验性噪音调整其鸣声频率。本研究旨在探究此类针对噪音波动的响应是否依赖于个体对噪音的熟悉程度。本研究证实，栖息于噪音区域的雄鸟鸣声频率高于安静区域的雄鸟；但仅栖息于已有噪音领地的雄鸟，会在遭遇实验性噪音时立即上调鸣声频率。出乎意料的是，栖息于更为安静领地的雄鸟，在遭遇实验性噪音时反而会下调鸣声频率。上述结果表明，黑头山雀或许需要过往在噪音波动环境中的经历，才能通过调整鸣声最大限度地规避掩蔽效应。因此，学会应对噪音或许是适应城市声学环境的重要环节。