A Review on the Interpretation of Avian Distress Calls in Fowl (Gallus gallus) and Egret (Ardea alba)

Abstract

This review examines the significance of distress calls in birds, focusing on two species: the domestic chicken (Gallus gallus) and the great egret (Ardea alba). Distress calls are vital vocalizations produced in response to immediate threats such as predators, environmental disturbances, or social conflict. These calls serve to alert conspecifics and facilitate survival by either startling predators or eliciting mobbing behaviors. The review explores the physiological and acoustic characteristics of distress calls, highlighting their complexity in domestic chickens, where calls are influenced by multiple stimuli, and the simpler, predator-related calls of great egrets. Additionally, the review addresses the evolutionary significance of these calls, their role in social dynamics, and their seasonal and environmental variability. The impact of habitat types on distress call characteristics is discussed, with birds in urban environments adapting their calls to higher frequencies to avoid masking by ambient noise. Moreover, the paper explores the use of distress calls in conservation strategies, particularly in monitoring bird populations and detecting environmental stressors. Distress calls can serve as early warning signals of ecosystem health and offer a non-invasive method to assess avian welfare. Finally, the review identifies gaps in current research, including the need for better standardization in methods and further investigation into the neurological and hormonal responses triggered by distress calls. The integration of advanced technologies like bioacoustic monitoring and machine learning is recommended to enhance the study of avian vocalizations, ultimately contributing to improved wildlife management and conservation efforts.