Vocal repertoire of adult captive red pandas (Ailurus fulgens)

Vocal signals are a common communication tool used to recognize different individuals, advertise fertile phases or discriminate amongst potential mates. Therefore, a thorough understanding of vocal repertoires forms the basis for investigating the role of acoustic signaling in the sexual and social behavior of any animal. Red pandas (Ailurus fulgens) are classified as a vulnerable species and have declined by as much as 40% over the past 50 years in China. Adult red pandas are known to call frequently during mating and aggressive encounters; however, no quantitative description of their vocalizations has been attempted. Here, the vocal repertoire of captive red pandas was investigated. Acoustical and statistical analyses indicated seven vocalization types during the breeding season: “growl”, “bark”, “squeal”, “bleat”, “hoot”, “grunt” and “twitter”; the spectrogram for each vocalization type was extracted. The type of vocalizations produced varied with behavioral state and implies different functional contexts. Future studies are needed to uncover the functions of red panda vocalizations in individual recognition, sexual selection and social interaction.

声信号是动物用于识别不同个体、宣告发情周期以及甄别潜在配偶的常见通讯工具。因此，全面解析鸣声库（vocal repertoire）是探究声学信号在任意动物的性与社会行为中所扮演角色的基础。小熊猫（Ailurus fulgens）被列为易危物种，过去50年间中国境内的种群数量降幅最高可达40%。已知成年小熊猫在交配与攻击性互动期间会频繁发出叫声，但目前尚未有针对其鸣声的定量描述研究。本研究针对圈养小熊猫的鸣声库展开了探究。经声学与统计分析，本研究在繁殖季中共识别出7种鸣声类型，分别为"低吼（growl）"、"吠叫（bark）"、"尖叫（squeal）"、"柔鸣（bleat）"、"鸣啼（hoot）"、"咕哝（grunt）"与"唧啾（twitter）"；并提取了每种鸣声类型的声谱图（spectrogram）。所发出的鸣声类型随行为状态发生变化，暗示其对应不同的功能场景。未来仍需开展相关研究，以揭示小熊猫鸣声在个体识别、性选择以及社会互动中的具体功能。