Biodiv Sci ›› 2023, Vol. 31 ›› Issue (1): 22523.  DOI: 10.17520/biods.2022523

• Original Papers: Animal Diversity • Previous Articles     Next Articles

Diel and seasonal variability of the forest soundscape in the Northeast China Tiger and Leopard National Park

Yifei Sun1,2,3, Shizheng Wang1,2,3, Jiawei Feng1,2,3, Tianming Wang1,2,3,*()   

  1. 1. National Forestry and Grassland Administration Key Laboratory for Conservation Ecology of Northeast Tiger and Leopard, Beijing 100875
    2. Ministry of Education Key Laboratory for Biodiversity Science and Engineering, Beijing 100875
    3. College of Life Sciences, Beijing Normal University, Beijing 100875
  • Received:2022-09-13 Accepted:2023-01-08 Online:2023-01-20 Published:2023-01-30
  • Contact: *Tianming Wang, E-mail:


Aims: Passive acoustic monitoring (PAM) and acoustic indices could provide an effective method for monitoring changes in forest soundscapes. However, annual dynamics of soundscapes remain poorly understood. We studied the diel, seasonal patterns, and shifts of the biotic component of the acoustic environment in the Northeast China Tiger and Leopard National Park.

Methods: We sampled recordings at 52 sites from June 2020 to June 2021 within the park. For each recording, we calculated the acoustic complexity index (ACI), acoustic diversity index (ADI), acoustic evenness index (AEI), bioacoustic index (BIO), normalized difference soundscape index (NDSI), acoustic entropy (H), and power spectral density (PSD) of each 1 kHz frequency bin within the 1-21 kHz frequency band. We divided a diel cycle into 4 phases (dawn, day, dusk, and night) according to the times the sun rose and set, and utilized generalized additive models (GAMs) to fit the curves of the diel and annual patterns of acoustic indices.

Results: The soundscapes demonstrated a marked distinction among all four phases, especially between night and other time periods. The soundscapes typically had more acoustic complexity, diversity, and biophony intensity during the daytime. However, night soundscapes showed more acoustic complexity throughout the summer season. In spring, the acoustic diversity index and bioacoustic index were higher at dawn due to intensive bird choruses. Acoustic complexity, diversity, and intensity of biophony demonstrate varied annual dynamics and peaked from May to October.

Conclusion: This study identified measurements that effectively summarize baseline soundscape attributes and prioritizes future opportunities for integrating non-acoustic and acoustic variables in research in order to inform area-specific management questions within the Northeast China Tiger and Leopard National Park.

Key words: ecoacoustics, forest soundscape, acoustic indices, Northeast China Tiger and Leopard National Park, biodiversity monitoring