Acoustic diversity of forested landscapes: Relationships to habitat structure and anthropogenic pressure

Abstract

Understanding how human-dominated landscapes affect biodiversity and ecosystems is essential for effective conservation planning. This work aims to understand the relationship between the acoustic diversity of forested landscapes, and descriptors of habitat structure, composition, and anthropogenic pressure, as well as to identify the characteristic scale at which acoustic community diversity relates to those metrics in central Massachusetts.Ten passive acoustic recorders were placed within forest areas in central Massachusetts, during the breeding season. Mono audio recordings were collected during the dawn chorus. The relationship between acoustic indices (AI), and core habitat quality, connectivity, vegetation productivity, percent tree cover, human edge, artificial illumination, and traffic noise were assessed.Significant relationships were found between AI and variables related to habitat structure and human pressure. Sounds related to biota (biophony) and acoustic complexity were positively correlated with core habitat quality, connectivity, and vegetation while negatively correlated with human pressure variables, including nighttime lights, traffic noise, and human edge. AI can therefore act as successful indicators of habitat quality in highly modified landscapes The highest correlations were found at buffers between 1.5 and 3 Km. This response of AI to the broad spatial context and not to the local site characteristics indicate that they can act as robust landscape-scale indicators.The large characteristic scale indicates that urban planning should consider potential impacts acting at scales beyond site planning. Moreover, conservation planning can benefit from managing the context matrix to support biodiversity, particularly traffic noise and artificial illumination reduction initiatives.