Temporal patterns and environmental drivers of the red junglefowl vocalization.

The vocalization behaviour of birds is influenced by multiple factors, such as reproductive status, photoperiod and climatic conditions, which drive adjustments in their calls to respond to environmental changes. This study employed passive acoustic monitoring and automated signal recognition technology to analyse the daily and seasonal variations in the vocal rhythms of the red junglefowl Gallus gallus jabouillei over a complete annual cycle, examining the impact of climatic factors on their calling activity. Results revealed significant diurnal and seasonal variations in the vocalization behaviour of red junglefowls. The daily activity patterns showed distinct morning and evening peaks, occurring one hour before sunrise and sunset, respectively. During the breeding season, calling activity progressively increased, reaching its peak during the incubation and brooding periods. The vocal intensity of red junglefowls fluctuated with environmental changes, showing significant associations with daily precipitation and morning temperatures but was unaffected by daily maximum wind speeds. During the full moon, the morning peak was observed to occur earlier than during other lunar phases, whereas the evening peak consistently coincided with sunset. This study further suggested the optimal sampling periods and minimum monitoring durations required to track red junglefowl vocal behaviour, offering guidance for call-based population surveys and passive acoustic monitoring.