Often over- and mis- used, the word noise means something specific in the context of acoustic ecology and field recording. It is generally an unwanted element, whether natural or a product of equipment/software. We can talk about wind noise in a calm soundscape, or microphone self noise in a very soft recording, or digital noise generated by quantisation. 

From an acoustic ecology perspective, anthropogenic noise (alternatively anthropophony or anthrophony) is an ever-increasing side effect (and sometimes desired outcome) of urbanisation, modernisation, globalisation etc. Very clear examples of this include the sounds of aircraft flying over, road traffic, industry, ocean traffic, sonar, weapons testing and many others. A slightly different way to look at it is to consider natural quiet - the absence of human-made noise and the presence of natural sounds. 

Sound recordists try to get the best signal to noise ratio by getting very close to their sources, using high quality kit (microphones, preamps, recorders) and by recording at the correct gain values. For someone like me who records natural soundscapes for a living, anthropophony is a perpetual nemesis. It’s also a challenge I’ve worked hard to overcome - learning a lot in the process. 

I take considerable pride in having had a pretty feral childhood, roaming the wild hills and forests in NE Romania. My childhood memories are mostly of pristine natural spaces full of birdsong, of heavy winters with crazy blizzards and mountains of snow, or of clear streams and rivers full of wildlife. I have no recollection of distant sounds of traffic though.

That does not mean it was not there. Our brains (the auditory cortex in particular) are adept at stripping away irrelevant content, like the distant sound of road traffic when you’re a 7-year old exploring a previously unknown part of the local forest. 

Even later in life, most people don’t register all the various elements of anthropophony they can hear at any given time. Whether it’s the din of traffic, the voices of neighbours arguing that filter through walls or low vibrations from heavy vehicles passing on the roads nearby - this is all discarded in favour of more immediately relevant acoustic information.

I won't go into the wider implications of anthropogenic noise and its effects on animals, including humans. Here’s a bit of reading if you’re interested in this: 

https://royalsocietypublishing.org/doi/10.1098/rsbl.2019.0649

https://www.frontiersin.org/articles/10.3389/fpsyg.2020.570694/full

So how did I become aware of my newly identified nemesis? Well, the first time I put on a pair of headphones so I could listen to the world through microphones, all this content that my brain was not registering became painfully apparent. I was in a semi-urban park and I could hear birds singing, soft wind in the trees and ducks at a pond, but listening through headphones added vehicle engines, aircraft and people playing a football game nearby to the mix. I was not expecting this to be a pristine, untouched soundscape, but I wasn’t ready for all the anthropophony either. 

Many years later, I can disengage the management part of my auditory cortex so that I can be fully aware of what I’m listening to. If I’m in the recording mindset, I can identify sounds that I would normally not be aware of. Sometimes I can hear things I’m not supposed to or don’t want to hear. 

Even so, certain sounds can be masked in a complex soundscape. Others are just below the threshold of hearing, but will still come up in recordings. This is where, as a sound recordist, I have to work extra hard to avoid capturing distant man-made sound when I’m after clean nature ambience.

It’s worth mentioning that clean or pristine natural soundscapes are mainly relevant for purposes like sound design or meditation. In other fields it can be argued that focusing on clean ambience is missing the point, and the best way to do it is to record everything as it is. I have mixed feelings about this - on one hand I agree that only presenting clean recordings might be misleading, but on the other hand these recordings are needed, if only to preserve the sound of these spaces for posterity. Let me offer some examples so you can better understand where I’m coming from.

In the Amazon rainforest I had to contend with the constant sound of distant boats, from Peru to Colombia and Brazil. During the day, it was mostly people fishing or travelling from village to village. At night, smugglers, cocaleros, loggers, miners, pirates and other illegal activities. Close to rivers, the din never died down. I had to walk through the jungle for many miles away from navigable waterways before I could get away from man-made sound. It was a similar story in mangrove forests in Borneo, coastal deltas in Senegal or estuaries in Madagascar.

In the inland rainforest in Borneo and Madagascar it’s very difficult to avoid the sound of mopeds and motorcycles. People living and working in plantations (oil palm, fuelwood eucalyptus, cash crop vanilla etc) move around on these very noisy vehicles, and have to do so constantly day and night. The sad reality is there is much more plantation than old growth rainforest in these areas, and the disparity keeps growing. It’s almost impossible to get far enough away from man-made sound, because there is rarely enough forest to offer shelter from it and to preserve some natural quiet.

In the savanna areas of sub-saharan Africa, subsistence agriculture and cattle farming permeates the boundaries of most “wild” areas. The Masai Mara has become home to many cattle herds, with the tacit approval of authorities and at the expense of wildlife populations because of increased human-wildlife conflict. While the sound of cattle mooing isn’t as damaging as distant engines, it is still associated with humans in the minds of wild creatures, with all the expected implications. It is also something I try to stay away from when recording wild soundscapes, with varying degrees of success.

The high altitude plateaus of Ethiopia - which are home to the Ethiopian wolf, the rarest canid in the world - have become grazing grounds for sheep and goat herds that bring guard dogs along. In similar fashion, Fulani herders move constantly around the Sahel and south into savanna. While they’ve done this for aeons, it is now becoming a problem because of overgrazing, human-wildlife conflict and conflict with non-nomadic populations. As more people move in, the natural quiet goes away.

These are extremely complex issues that involve humans, wildlife and nature equally. They are not clearly negative or positive, and require sensible approaches at a variety of levels. I don’t have any answers or suggestions on how to keep wild spaces wild. I don’t even know how realistic or beneficial it is to intervene in these situations. Knee-jerk reactions like banishing people from national parks can be even more damaging in the long term. 

From an acoustic ecology perspective, it’s a difficult proposition to draw the line between what should be there and what is considered noise. Sometimes it is a matter of labelling a soundscape as countryside rather than wilderness. That sounds fair if the recording includes the sounds of cattle, roosters or people tilling the fields. It might also work if there’s the occasional distant engine. But anything more “human” is where it becomes clear that it is not a naturally quiet soundscape anymore.

As soon as you start asking these questions, you have to consider the philosophical implications of where humans sit in the overarching order of things. There are clear arguments for separating what’s natural from what is man-made or man-introduced. The sound of constant city traffic is damaging for your mental wellbeing, according to many authoritative sources. Exposure to naturally quiet nature is beneficial, according to many of the same sources. What sets these two extremes apart is how much influence humans have on these environments. 

At the other end of this spectrum, we humans live in the environment, and thinking of ourselves as superior and/or separate from it can only deepen this divide. There’s an argument for considering ourselves as part of nature so that we feel more connected to it and hopefully more inclined to protect the wild spaces left - soundscapes included. 

Over the years I have worked in countless places that might seem amazingly wild. The Congo basin rainforest, the Atacama and Namib deserts, South Luangwa in Zambia, Yucatan peninsula in Mexico, the Sahel in Senegal/Mauritania to name only a select few. In each and every one of these places, humans have lived for ages, in smaller or larger numbers. They have left their mark on the environment, to greater or lesser extent. They’ve influenced the soundscapes and continue to do so. While some effects can be detrimental, successful conservation endeavours require working with the humans who call these places home, and that includes the soundscape as well.

Originally written for Earth.fm. George Vlad is a sound recordist, photographer and expedition leader who specialises in recording remote soundscapes, rare wildlife and extreme environments. Fore more information check out his website - listen to his work on his Youtube channel.