Impact of Noise on Animals and Birds
Even though we might consider loud noises as a nuisance and might crib about it, our misery is nowhere near as fatal as compared to animals and birds.
Without the myriad technological and cultural mediums of escape at their disposal that we humans tend to take for granted and abuse, birds and animals are irrevocably dependent on their immediate environment for survival.
Fauna has a much deeper association with their surrounding environment, in which sound forms a fundamental part, especially when it comes to threat detection, presence of food, availability of mating partners, and many more aspects.
What happens when the rich system of stimuli that is the habitat of animals and birds is bombarded with human-made noises, disrupting natural signals and disorienting almost every species in its natural functioning?
The effects are disheartening to say the least.
Noise can cause PTSD in Birds
A study that appeared in the Proceedings of the National Academy of Sciences detailed an experiment in which differing levels of noise was used to test and analyze the reactions of different species of birds.
The results should that high levels of noise induced PTSD-like (Post Traumatic Stress Disorder) symptoms in birds, with reactions that were quite similar to that of humans who suffered from debilitating psychological trauma due to war or other intense experiences.
One of the fundamental reasons behind these symptoms amongst birds was that they were not able to understand and coordinate their hatching and nurturing cycles in accordance to fundamental natural cues.
Without access to the natural sounds of their immediate environment, which was muffled by loud noises, birds were unable to understand whether there were low enough levels of predatory presence and thereby, were confused as to whether or not to lay their eggs.
Those bird species that laid eggs in this noisy environment where further confronted with the decision to either stay guard or to go foraging for food. The loud noises triggered an instinctive sound-based impulse that a predator was near, forcing the parent to stay guard on the young. The constant noise disrupted foraging cycles while also increasing stress levels considerably.
The poor birds were constantly bombarded with predatory cues, putting them in a similar situation as how a human would feel in a warzone.
Furthermore, stunted growth amongst hatchlings was also observed in high noise areas. Simultaneously, rates of successful hatching also fell considerably due to high levels of noise in the environment.
Noise can Cause Birth Defects in Animals
A study conducted in 1998 by researchers Anders Mollen and John Swaddle, titled ‘Asymmetry, Developmental Stability, and Evolution’ found that increased exposure to noise amongst pregnant mice resulted in deformed pups which showed signs of skewed bone growth.
Other studies, conducted as early as back in the 1970s show that growth rates amongst species such as the brown shrimp is reduced to a considerable extent even when environmental noise levels increase by 30%.
It is clear that noise impacts animals even in their embryonic stages within the womb, a fact that rings true even for humans. A study found that the young ones of a species of duck known as the Muscovy Duck, showed behavioral changes that were a direct result of the noise prevalent in the environment around the mother.
Environmental noise, specifically those generated from human activities, also tend to disrupt a subtle form of communication in the animal kingdom which most people might not even have heard about before.
Did you know that there is a form of communication known as inter-egg communication which occurs between embryos and facilitates a phenomenon called hatching synchrony?
The foundations of inter-egg communication come from the ability of one embryo to detect the heart beat of another that is present in the egg besides it. Based on the heart rate of the embryos in the surrounding eggs, an embryo is able to adjust its metabolism rate so as to coordinate hatching in such a way that all the young emerge at a similar time from their respective eggs.
Environmental noise makes it difficult for embryos to detect subtle cues such as heart beats from their surrounding environment, thereby wreaking havoc with embryonic metabolism levels, hatching times, and overall development within the egg in species like snakes, turtles, and others.
Noise Impairs Cognitive and Physiological Development
One debilitating impact of noise that has been studied over the years is the fact that increased exposure to noise can in fact decrease the ability amongst bird species to “sing” the tunes that they normally produce in the wild.
This impact was observed amongst species such as the Zebra finch, which were found unable to produce the natural vocalizations that they utilize in mating rituals and communication in general, after exposure to short and long term extreme decibel levels.
Birdsong has been associated with fundamental cognitive development in birds, similar to how linguistic ability in humans has been associated directly with cognitive growth, especially amongst children. This showcases that noise has the ability to impair cognitive functions and debilitate the normal everyday capabilities required for basic activities amongst animals.
Noise exposure has been linked to learning deficits amongst species of rats in controlled conditions, where it was found that they demonstrated lower levels of spatial cognitive understanding (awareness of immediate environment) when exposed to high decibel levels.
Numerous species have also found to be suffering from neural degeneration due to exposure to noise. As soon as these animals/birds were moved away from a noisy environment to a quieter one, their neurons started regenerating and growing again at nominal rates of development.
Noise exposure has even been linked to genetic changes and chemical cascades that can cause fundamental changes in the micro-biological functioning of animals and birds. Studies showed that high levels of noise reduce the proliferation of a specific type of receptor in the brains of animals, such as rats, pertaining to a neurotransmitter known as GABA (Gamma Amino Butyric Acid). GABA is especially involved in reducing stress in the body and bringing the body back to baseline “peace” after a stressful episode.
Nature Finds a Way – Directions for the Future
Noise is a direct result of development, especially on an industrial level, and hence is a defining factor when it comes to the modern way of life adopted by humans. However, even though the source of noise is advancement, its impacts and consequences, especially for other species of animals and birds, are destructive in nature.
Amidst this cacophony that has been created by humans, nature has found its own way out of a messy situation. Some species of birds have adapted to high noise environment by modulating vocal patterns accordingly.
An Australian study found that species of birds known as ‘Silvereyes’ have evolved differently in urban and rural areas. Birds in urban areas were found to sing at higher frequencies in order to ensure that they were heard about the din of man-made noises. Their songs were also slower as compared to rural birds, signifying that the birds were making changes in order to ensure higher clarity amidst the chaos of noisy urban spaces.
Another interesting finding in numerous studies across the years was that music had a profound positive impact on all aspects of animal/bird life, from hatching cycles and embryonic development to cognitive development and genetic growth. This shows that music is a definitive universal blessing that is highly beneficial to both humans and animals.
Maybe, it is time to make our cities more musical and do away with noise that is pleasing to neither human nor animal.
Let’s join hands to bring down
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