Work

BirdNET provides superior diversity estimates compared to observer-based surveys in long-term monitoring

Year: 2025

Type: article

Abstract: Bird population monitoring is crucial for understanding biodiversity trends, with various methods differing in effectiveness. This study compared traditional observer-based methods, including point counts and manual analysis of passive acoustic monitoring (PAM) recordings, with automated species detection using BirdNET during springtime in the European primaeval forest, Białowieża National Park in Poland. We evaluated 97 10-minute surveys from each method and introduced all-day recordings into BirdNET to explore the differences in alpha richness and beta diversity at the survey level and cumulative from the entire breeding season.The results showed that BirdNET detected the highest alpha richness when processing all-day recordings. However, its performance during short-term surveys was less effective compared to that of human observers, with PAM yielding the highest species count among the observer-based methods. Beta diversity also differed according to the site and method used. The number of species detected during all short-term surveys showed a weak correlation with the number of species obtained from all-day BirdNET analysis, questioning the adequacy of short-term surveys in species-rich habitats like primaeval forests.Our findings demonstrate the need to adjust the monitoring method, whether automated or manual, to achieve more comprehensive monitoring results. Automated analysis offers scalability and efficiency, but it still requires significant time dedicated to processing, and manual review remains essential for validating automated classifications and ensuring data accuracy. In contrast, point counts and recording analysis can provide valuable insights in situations where time is limited or when finer verification of species detection is necessary.

Source: Ecological Indicators

DOI: 10.1016/j.ecolind.2025.113747