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Burgeoning urbanization, development and human activities have led to reduced opportunities for nature experience in quiet acoustic environments. Increasing noise affects both humans and wildlife alike. We experimentally altered human‐caused sound levels in a paired study using informational signs that encouraged quiet behaviours in week‐on, week‐off blocks on the trail system of Muir Woods National Monument, California, USA to test if the soundscape influences both wildlife and human experiences. Using continuous measurements from acoustic recording units (n = 13) spatially distributed within the park, we found signs significantly lowered sound levels by approximately 1.2 decibels (A‐weighted), thereby increasing listening area by 24% and bird availability by approximately 5.8% for every 1 decibel decrease. Visitor‐intercept surveys (n = 537) revealed that our mitigation increased the number of birds perceived by visitors, rankings of soundscape pleasantness, and importantly, preferences for soundscape management. By lowering human‐caused sound levels, we created an acoustic environment equivalent to a ~21% reduction in visitors. The positive feedback cycle we describe may lead to increased conservation support in a time when the extinction of nature experience looms. A free Plain Language Summary can be found within the Supporting Information of this article.

Protected natural areas are not free from noise, especially noise generated by traffic within park boundaries. Natural soundscapes are important for maintaining community structure, providing positive visitor experiences, and increasing visitor support for management actions that reduce impacts on natural resources. To test experimental quieting as a strategy to increase both wildlife habitat quality and visitor experience, we enforced decreased speed limits and presented educational signage to reduce sound levels along a road system in an alternating, on-off block design within Grand Teton National Park, Wyoming, USA. We continuously recorded background sound levels while conducting bird space use assessments and visitor-intercept surveys along the experimental corridor. Our mitigation approach lowered sound levels during sign-present weeks, yet there was no relationship between bird space use near roadways and traffic noise, perhaps due to the increased duration of noise exposure created by lower speed limits. There was, however, a relationship between visitor perception of birdsong diversity and background sound level. Critically, visitors preferred soundscape mitigation strategies limiting personal access in exchange for better experiences in natural soundscapes.

A growing body of evidence suggests that traffic noise negatively affects wildlife. Protected natural areas are not free from noise exposure, both external to and within park boundaries. Natural soundscapes are important in many aspects of animal life histories, for increasing positive visitor experiences, and for providing psychological ecosystem services. To examine the use of signs as an effective traffic noise mitigation strategy, we experimentally altered speed limits from 45 mph to 25 mph, with additional educational signage, along the Oxbow Bend traffic corridor in Grand Teton National Park, USA. We continuously recorded sound levels between alternating week-long blocks while conducting avian point counts at each station. We detected 2,217 individuals of 48 species across all stations throughout the study. To assess visitor experiences with the soundscapes and visitor attitudes towards sign use and management strategies, we conducted stated-choice intercept surveys along a park turnout within the experimental corridor. We administered 471 surveys at an 82% response rate. Future data will evaluate impacts of traffic noise on avian abundance and distributions, visitor attitudes towards mitigation strategies, and the potential coupling between human and natural systems via the soundscape. Featured photo from Figure 2 in report.

Protected areas are critical locations worldwide for biodiversity preservation and offer important opportunities for increasingly urbanized humans to experience nature. However, biodiversity preservation and visitor access are often at odds and creative solutions are needed to safeguard protected area natural resources in the face of high visitor use. Managing human impacts to natural soundscapes could serve as a powerful tool for resolving these conflicting objectives. Here, we review emerging research that demonstrates that the acoustic environment is critical to wildlife and that sounds shape the quality of nature-based experiences for humans. Human-made noise is known to affect animal behavior, distributions and reproductive success, and the organization of ecological communities. Additionally, new research suggests that interactions with nature, including natural sounds, confer benefits to human welfare termed psychological ecosystem services. In areas influenced by noise, elevated human-made noise not only limits the variety and abundance of organisms accessible to outdoor recreationists, but also impairs their capacity to perceive the wildlife that remains. Thus soundscape changes can degrade, and potentially limit the benefits derived from experiences with nature via indirect and direct mechanisms. We discuss the effects of noise on wildlife and visitors through the concept of listening area and demonstrate how the perceptual worlds of both birds and humans are reduced by noise. Finally, we discuss how management of soundscapes in protected areas may be an innovative solution to safeguarding both and recommend several key questions and research directions to stimulate new research.