Sound as an Element in Coupled Natural and Human Systems

Recent scientific research has demonstrated that human-generated sound can have a significant impact on the functioning and character of natural ecosystems and on human well-being. This interdisciplinary research project will study the interactions between natural and human systems as they are influenced by human-generated sound through analyses of the role of acoustics in affecting the number and diversity of birds and related human activity. The project will enhance basic understanding of the interactive effects that noise has on bird diversity and on the perceptions and actions of people. The project will provide a test of the hypothesis that as bird diversity declines when human-made noise fills the soundscape, individual and group valuation of wildlife and the acoustic environment decline, thereby reducing support for nature conservation, which ratchets declines in bird diversity further downward. The project also will test the corollary hypothesis that when natural sounds are a dominant input to the acoustic environment, the natural sounds have positive effects though the maintenance of biodiversity and more positive human perceptions of the natural world and the overall human experience with nature. Because the research will be conducted by an interdisciplinary team of researchers drawn from a diverse set of fields, including ecology, zoology, economics, resource management, human-environmental interactions, engineering, and education, it will advance the integration of social and ecological sciences to better assess and explore varied management approaches to contribute to the effective management of natural areas. The investigators will further the project's impact by actively employing citizen scientists in the collection of data, thereby increasing knowledge, awareness, and understanding of scientific concepts and techniques among those involved in the research effort. The project also will provide special interdisciplinary education and training opportunities for undergraduate and graduate students and for post-doctoral researchers. This project is supported by the NSF Dynamics of Coupled Natural and Human Systems (CNH) Program.

The investigators will conduct this project at both local and regional scales. At the local-scale, they will conduct playback experiments of the natural and human-related components of acoustic environments to examine sensory awareness gauged through changes in bird diversity, the use of space by people, and human well-being. They will experimentally examine the relationship between background sound level and urban biodiversity as well as its coupled relationship with human experience in nature. They will manipulate the soundscape of local natural areas using arrays of speakers. In one set of experiments, they will artificially elevate noise levels in natural areas by adding additional traffic noise to assess its impact on bird biodiversity and human perceptions. They also will experiment with the playback of bird choruses containing varying numbers of bird species but the same acoustic power in laboratory and city park settings, coupling data from these experiments with data from surveys and biomarkers to measure the psychological benefits and physiological response to different sound stimuli. At the regional scale, the investigators will evaluate how sound-management strategies affect space use by birds and people in Grand Teton National Park, and they will assess the human valuation of their experiences under different strategies.