For those who know how to listen, the most deafening noise in nature, is the sound of silence. It may come as a surprise to learn that what we measure or hear, is the creaking, groaning and often-times, slow shattering of ecosystemsHow ecosystems function An ecosystem is a community of lifeforms that interact in such an optimal way that how ecosystems function best, is when all components (including humans and other animals) can persist and live alongside each other for the longest time possible. Ecosystems are fuelled by the energy created by plants (primary producers) that convert the Sun's heat energy More. Acoustics, as scientists call it, is the measure of things under stress. It’s the ultimate in cognitive bias. What we think we are studying is the part of nature that animals are always trying to avoid. That should teach us that a quieter world is one we need, as it’s the world animals need to restore ecosystems for us. Successful animals manipulate silence to build a liveable world.
How successful animals manipulate silence
Animals use sound very carefully. Have you wondered why forests are often silent? When animals make sound, it’s not to attract other animals, it’s to keep them at bay. Making too much sound attracts unnecessary attention.
Birdsong happens at dawn and dusk, as this is the time least likely to interfere with feeding. A quick reminder early morning that this is your patch, minimises the risk of competition. Competition, after all, is the antithesis of survival. Animals that fight fail in the evolutionary arms race. In actual fact, it’s not a race at all … and it’s not a call to arms. It’s a constant struggle to yield to greater forces that constantly undermine a species’ existence. It’s about fitting in.
Animals couldn’t exist, unless they used sound sparingly, to avoid interference with others.
Earth’s disappearing silence
The BBC just published a lovely article with Gordon Hempton where he talks about the most endangered sound of all: silence. An increasingly noisy world isn’t just threatening our peace but undermines the functioning of ecosystems, by disrupting harmony between animals.
There are only two places in the world I’ve experienced silence in the last ten years. The first was sitting on board the Pindito on one of our expeditions to West Papua one evening after sunset. Everyone had gone to bed. Generators were turned off and it was completely dark, apart from starlight. The second was with Andrew Skeoch in the rainforest of far east Gippsland. It took travelling several hours from Melbourne to find the only place Andrew knows within several hundred kilometres, where there is no road noise.
How sound and silence defines animal society success
Noise has become such a dominant part of our existence that it almost defines everything we do now. Thirty years ago I would sit in the Fat Cat pub in Norwich (UK) and apart from the chat between guests, there was no other noise. Today, restaurants and cafes turn music up so loud, you can’t even have a conversation. Numerous times, I have had to ask owners to turn down the sounds, so I can hear what someone sitting opposite, is saying.
Is there a better example of how blind (or deaf) we have become to our needs? We deliberately create eating spaces so noisy, we cannot even talk to each other.
As hunter gatherers, we would have used silence to find prey in the bush. We would have also kept silent, to avoid becoming prey ourselves. Animals like whales and dolphins use communication with each other as a way to create society and maintain family bonds. For the most part, they are silent, only using sonar to gather information about the world around. Even this can’t work in a noisy environment. Seismic surveys by the oil and gas industry threaten the ocean not so much by damaging animals’ hearing but by creating lasting damage to the acoustic fabric that holds the system together.
Seismic surveys (booming) and Sperm Whale Clicks. The noise is often continuous for many months. It makes prey more nervous and predators less likely to hear. Noise impacts have been found throughout the food chainA single thread in a food web illustrating the chain of animals that eat each other. At the base of the food chain are small high-energy (fast metabolism) animals and at the other end large low metabolism animals. An example would be whales eating krill that eat plankton that eat algae. Or lions that eat gazelles that eat grass. More all the way from planktonA soup of micro-organisms. Usually refers to all the zooplankton and algae in the ocean but can also be used to describe tiny insects in the atmosphere (see aerial plankton). More to whales. Visit https://ocean-sounds.org/
Shipping noise recorded from a container ship doing 16 knots in Washington. Thanks, Gerald Graham.
Predators can’t detect prey in noise and prey can’t relax when they can’t hear. This is why land animals tend to get nervous on windy days. Most mammals have more acute hearing than us and for them, noise is like having a bright torch shone in your eyes.
We need to embrace the value of silent ecosystems to be successful
As ecologists, we too often study change in landscapes, which is an after-effect. When it comes to soundscapes, noise is both a consequence and driver for this change. As ecosystems break down, they become noisier, because animals are thrown into competition. Fights ensue and as fewer animals survive, ecosystems break down and we lose out.
Scientists can hear and describe noise, whereas an intact world is too abstract to comprehend. How can you measure silence? This cuts to the heart of one of our greatest cognitive flaws. Science usually measures things by altering them, at which point it’s too late to know whether what came before, would have been better for us. It’s like we spend our time concentrating on the opposite of what’s natural and good for us.
Sound is the ultimate metaphor for what we can get wrong in ecology. Successful animals manipulate silence but we focus instead, on the rarer moments when they break the silence. So we convince ourselves that noise is used to survive, whereas it’s actually silence.
A great musician, they say, becomes a master at playing the gaps between the sounds, not just the sounds themselves.
