Have you ever been jolted by a sudden loud noise? Now, imagine experiencing this constantly in your home. For many animals, this is a jarring reality. Recent studies reveal that nearly 14% of the Earth’s land area is affected by anthropogenic noise, a figure that’s doubled in the past five decades. From the deepest oceans where whales communicate to the vast savannahs where elephants roam, noise pollution is changing the very fabric of animal communication, navigation, and even mating rituals. The silent toll of blaring horns, rumbling engines, and distant machinery is reshaping the natural behaviors of countless species. So, in this blog, we’ll discuss the changes in animal behavior due to Noise Pollution.

What is Noise Pollution?

Noise pollution, often an unintended outcome of urbanization, transportation, and industry, is essential to human development and population expansion. It is produced on purpose in some circumstances, such as when seismic surveys are carried out using robust airgun arrays to explore and map the seafloor, or active sonar, which employs sound waves to locate objects in the ocean. All of this noise, whether deliberate or unintentional, can affect the acoustic environment of aquatic and terrestrial environments. This can significantly impact the animals, bringing changes in Animal Behavior due to Noise pollution that lives in them, potentially causing evolutionary change as species adapt to or avoid noisy surroundings.

Noise is not only annoying; we have known for some time that it can directly influence human health. Chronic exposure to noise levels above 55dB significantly increases the danger of heart disease and stroke. In contrast, aviation noise has been proven to impact the development of reading skills in children attending schools near busy airports.

What Are The Difficulties of Sound Level Measurement?

Noise analysis is a difficult task. Unlike temperature, rainfall, and wind speed, sound levels cannot be precisely measured and quantified using a single absolute scale. We frequently refer to decibel levels for ease. However, this does not account for the duration and frequency of the auditory input. Noise’s unique effects must also be distinguished from the sources of disturbance that frequently accompany it, such as human presence, habitat fragmentation, and chemical pollution.

Understanding the complicated biological consequences of noise and establishing scientifically appropriate noise exposure thresholds is a priority for human health and wildlife conservation. Rapid development, urbanization, and population increase are expected to continue. As a result, we must guarantee that science, industry, and government work together to safeguard natural soundscapes wherever possible while supporting innovative technology and practices that lessen the effects of noise.

Artificial noise is a relatively new phenomenon, especially in evolutionary timeframes. Yet, scientific investigations have shown that it can influence behaviour, change physiology, and even reconstruct animal populations. Such a high selective pressure could eventually force evolutionary change. These are complicated problems that professionals are now investigating, from animal behaviour to bioacoustics.

How Can Noise Pollution Affect Animal Behaviour?

Over the last decade, scientific interest in the consequences of noise pollution on wildlife has increased. We are now acquiring a better knowledge of how noise might alter behavioural, population, and community-level processes in various animal species. The evidence obtained from this research, which used experimental and observational methodologies to describe and study the specific effects of different noise sources, is substantial, notably among songbirds and marine mammals, who rely primarily on sound and vocal communication. Ship noise, for example, has been shown to affect the foraging, verbal behaviour, and physiological stress of cetaceans (whales, dolphins, and porpoises). This is especially concerning for endangered species such as the North Atlantic right whale, which lives in coastal US seas with significant shipping traffic. Furthermore, military sonar has been connected to cetacean stranding in addition to distribution and vocal behaviour changes.

Noise has been shown to have significant deleterious effects on marine and freshwater fish, invertebrates, and marine animals. Recent research has shown that crabs and eels exposed to ship noise have poor anti-predator behaviours. Bird diversity and abundance have been demonstrated to reduce terrestrial habitats due to chronic noise levels surrounding cities and along roadways. Several species have altered their vocal behaviour to adapt to the cacophony of human sounds. Urban great tits, for example, can change the frequency of their calls to reduce acoustic masking by mostly low-frequency urban noise. Still, European robins time their singing to correspond with quieter periods in the city.

Impacts of Noise Pollution Animal Behaviour

Meanwhile, black-chinned hummingbirds and house finches actively seek out noisy regions near active gas wells to prevent nest predation by more sensitive species. Road noise has also been demonstrated to reduce the effectiveness of bat foraging and disrupt vocal communication in frogs and invertebrates. Although many animals rely on their hearing for survival, they are especially vulnerable to the difficulties that noise pollution (prolonged noise exposure) can create. Here are four activities that can be hampered by noise:

1. Communication

Animals, like humans, communicate by sound, and many species have developed individual sounds to warn others of danger, attract mates, or recognize their offspring or groups in a crowd. Soundscape ecologists’ recordings imply that various species within a habitat have specific acoustic niches, sounding out their calls at different pitches or intervals than other species to be heard. Humans can upset this equilibrium by making noise (e.g., aeroplane engines, construction equipment, lawnmowers), which drowns out critical communications.

2. Navigation

Nocturnal and watery animals have evolved differently to their low-light surroundings. Echolocation is a process used by bats and dolphins in which they make calls at a specific frequency and use echoes to identify obstacles and prey in the surroundings. Human-made disturbances (such as traffic or sonar) might confuse these animals by impairing their hearing or leading them to change the tone of their cries in ways that yield less helpful echoes.

3. Foraging

Owls and cats have evolved complex ears to assist them in hearing prey, but it is more arduous for them to do so in noisy situations. A one-decibel difference is scarcely perceptible to humans, but research indicated that for every 1dB increase in noise, owls in the region were 8% less successful at catching prey. The psychological effects of noise can have an impact on herbivory. One study discovered that noise attracted nectar-eating hummingbirds (raising pollination) but discouraged many seed-eating birds (decreasing seed distribution), showing that noise can alter the plant community of an environment.

4. Mating

Males in many species (especially birds and frogs) rely on specific cries to attract mates. Most beautiful sounds are low-pitched. However, some animals have been observed raising their voices to compete with low-frequency noises such as car engines. These less appealing vocalizations can impair males’ capacity to attract and retain mates. Furthermore, the calls resonate in loud situations over a narrower range, resulting in smaller breeding pools. Scientists are concerned about how noise pollution may reduce population levels and genetic diversity.

Some Measures To Protect Animals From Noise Pollution

1. When performing maintenance work, use quieter, non-mechanical tools and travel by foot if possible. If mechanical equipment must be used, become familiar with the behaviour and lifecycles of local species to avoid noisy maintenance during peak forage or breeding seasons. When acquiring new mechanical tools, search for quieter, more energy-efficient options!

2. Acoustic monitoring has become popular as a non-intrusive technique of recognizing animals with characteristic cries, such as birds, frogs, and bats. Listen for any human noises that dominate the soundscape so you can think about ways to lessen them. Compare the recordings over time to identify any changes in animal cries’ presence, pitch, or patterns.

3. Properly placed plants might aid in noise reduction. The ideal sound barriers are dense, native vegetation that spreads to the ground. An evergreen tree and shrub mix can provide year-round soundproofing. Put the vegetation near the noise source (such as a motorway or equipment room) rather than the natural area you want to protect for optimal impact.

Conclusion

Nature’s sounds, like bird songs and animal calls, are super important for our planet’s wildlife. But with all the noise we humans make, now we know how animals and noise pollution are related. From cars to machines, the natural sounds of animals are getting lost. Noise caused by humans messes with the way animals talk, find their way, find food, and even find friends! It’s like trying to chat with your buddy at a loud concert – pretty tough, right?

But here’s the good news: we can make a difference. We can use quieter tools, plant trees to block out noise, and be careful about when and where we make a lot of noise. By doing these things, we can make sure that animals can still live their best lives, and we get to enjoy the beautiful sounds of nature, too. Let’s work together to keep our world both lively and peaceful!

Also Read: Effects of Noise Pollution on Plants and Animals