Abstract:

Background & Aims: Rapid urbanization has proved the importance of effectively monitoring and evaluating urban bird diversity, making it a crucial area of technique inquiry within urban ecology and biodiversity conservation. Passive acoustic monitoring (PAM), a technique that utilizes the environment to assess biodiversity, provides long-term and continuous data on urban avian population dynamics. This approach offers valuable insights into the influence of human activities on natural habitats. Although PAM technology has been adopted globally for urban biodiversity monitoring and has resulted in extensive acoustic datasets, variations in monitoring and assessment methodologies show significant challenges in effectively evaluating urban avian diversity.

Review Results: We synthesize representative cases of urban avian diversity research conducted using PAM technology, focusing on aspects such as spatio-temporal experimental design, recording device parameters, and quantification techniques of acoustic signals. The results indicate that current case studies exhibit general routines in experimental frameworks, parameter selection, and quantification methods. However, variability in monitoring and evaluation technologies, along with their effects on factors such as signal-to-noise ratio and representativeness of sound signals, remains a significant challenge that hinders the application of PAM in urban bird diversity research, yet this issue has not received adequate attention. Therefore, this paper advocates for a comprehensive examination of passive acoustic monitoring and evaluation techniques for urban bird sounds, which would facilitate the creation of eco-acoustic big data and address broader ecological questions.

Perspectives: Given the increasing prevalence of PAM applications, there is an urgent need for the development of technical standards for passive acoustic monitoring and evaluation of urban birdsong. Establishing these standards would promote the standardization of sound data collection and analysis, leading to the creation of a comprehensive urban bird sound database. Such advancements would enable the utilization of big data to elucidate the impacts of urbanization on birdsong diversity and response mechanisms, thereby enriching urban avian studies and supporting biodiversity conservation efforts in urban environments. This paper summarizes current monitoring schemes and technological applications, providing a foundation for future theoretical frameworks. Methodological approaches and technological implementations are proposed for future passive acoustic monitoring and evaluation of urban bird diversity in China.

Key words: passive acoustic monitoring, urban ecology, bird diversity, ecoacoustics