Human Noise Hurting Animals—Possibilities and Challenges of Noise Reduction Technology

Human Noise Hurting Animals—Possibilities and Challenges of Noise Reduction Technology

The COVID-19 pandemic was an unprecedented crisis for humanity, but it also enabled a kind of “experiment.” Jennifer Phillips (first name only) made an unexpected observation during the pandemic: with urban traffic noise gone and flights drastically reduced, sparrow songs became far more audible.

This phenomenon provided an unprecedented situation in human history—one of simply “becoming quiet.” MIT Technology Review’s April 2026 article published a detailed survey report on how the “anthropogenic noise” humans produce day and night affects wildlife.

Ecological Impacts of Noise Pollution

In our daily lives, sound is not merely a “noisy” problem. According to ecology experts, artificial noise is fundamentally altering animal behavior patterns.

Taking birds as an example, singing is an important means of courtship and territory declaration. However, when it’s covered by traffic noise or construction sounds, communication between males and females is hindered, and breeding success rates are affected—findings that have been confirmed by multiple studies. Furthermore, noise stress has been shown to elevate corticosterone (stress hormone) levels in birds and negatively affect immune function.

The situation is equally dire in the ocean. Noise from ship engines and sonar surveys interferes with communication among marine mammals like whales and dolphins, potentially disrupting behavioral patterns essential for population survival. In some areas, declines in breeding behavior in waters with concentrated ship traffic have been reported.

The Value of “Silence” Shown by the Pandemic

Behavioral restrictions during the COVID-19 pandemic provided valuable data on this issue. In cities where people were confined to their homes, traffic drastically decreased, and flights were significantly reduced, background noise levels dropped dramatically. As a result, bird songs traveled farther than usual, and improved communication between individuals was noted.

Phillips’ question arises from this temporary silence: can we transform this into “permanent silence”? If we actively introduce noise reduction technology in urban design and transportation systems, coexistence with wildlife could make significant progress.

Technological Solutions

Currently, efforts are underway to apply noise reduction technology to wildlife conservation. The main approaches include:

Electroacoustic Reduction Technology: Research is advancing on applying active noise control technology to vehicles and aircraft. This analyzes surrounding noise and generates counter-phase sounds to cancel it out, making it more efficient than traditional passive soundproofing.

Low-Noise Pavement Materials: Development of special pavement materials to reduce tire-road noise on roads is also progressing. These materials have sound-absorbing properties and can significantly reduce noise from vehicle passage.

Soundscape in Urban Planning: An approach considering distance from noise sources and placement of sound barriers and green spaces at the urban planning stage is also being proposed. This method aims to achieve coexistence by properly separating wildlife habitats from human residential areas.

Future Challenges and Prospects

However, many challenges remain before these solutions can become widespread. The biggest issue is economic cost. Introducing low-noise technology requires higher expenses compared to conventional equipment and materials, making it difficult to apply to all vehicles and infrastructure immediately.

Additionally, the effectiveness of noise reduction technology is known to vary depending on the wildlife species. In some species, reduced human activity can反而 cause maladaptation, so standardized solutions rather than species-specific approaches are needed.

Phillips’ article concludes: “The pandemic made us realize how much noise we produce, while also teaching us how precious quiet can be. Applying this lesson to achieve harmony between humans and nature through technology may be the mission of our generation.”

Through future research and technological development, there is hope for achieving the difficult balance of maintaining urban life and transportation convenience while reducing the impact of human activity noise on wildlife.