Introduction

Freshwater – usually one of the first things we think about when we think about water, mainly because it is essential to us. At its source, freshwater takes many forms, such as creeks, streams, lakes, and rivers. When most people picture these water forms, they most likely associate both image and sound with each of those words. While the image component of the “picture” is interesting, the sonic part is arguably more so, as there are multiple perspectives involved. Although the soundscape as we hear it above water is generally familiar to everyone, many generally imagine what it sounds like underneath assuming it produces a sound similar to what they hear above the surface. This is a general misconception, and the actual sounds can be played and will be described in the following pages.

 

Freshwater is also interesting because of the life around the scene that is part of the soundscape and because of the flow of water and possible aquatic life underneath that influence the overall soundscape. Questions can be posed that relate to how the animals adapt to their soundscape and how external forces influence their surroundings. Obviously, this is a very difficult question to answer, as it is difficult, as humans, to gauge the feelings and thoughts of animals such as aquatic insects and fish. We can at most guess, based on the reactions of the organisms and behavioral psychology, how this life is being impacted by disturbances. Because of this, the scope of our experiment will be appropriately narrowed in order to focus more on how outside forces, such as animal sounds, etc. possibly affect the nature of the soundscape underneath.

 

Impact

Freshwater is home to many species, some of which are very small, such as insects and arthropods. Small animals must communicate, yet their body size creates mechanical constraints (Sueur). One such example is a very small insect, the water boatman (Micronecta Scholtzi). Their mating call includes three parts differing in temporal and amplitude parameters but not in frequency. They produce a relatively large amount of energy to compensate for their small size. Additionally, "anthropogenic activities such as pile driving, shipping, sonars, and underwater blasting" take a toll on fishes and marine mammals, as have been detected by underwater recording devices (Ren). Many of these human activities create sounds that are able to be detected by fish, and some sources create noise energy that is most sensitive to the fishes' auditory systems, causing possible damage to auditory sensitivity. Hearing loss, temporary or not, can diminish the awareness of fish and pose a survival risk. Because of this, it is worthwhile to study the impact of external forces (human or not) on an aquatic soundscape to better understand how the changes in soundscape could potentially affect other life.

 

"Natural Sounds"

What exactly is a natural sound? In this day and age, technology is so advanced that sometimes it can be difficult to clearly distinguish what is natural. Since humans have successfully integrated some technologies into daily life, this difference can sometimes be quite arguable. Take the example of boats on a river. Boats are a commonplace part of human life, but are boat sounds therefore "natural", or do we still limit the definition of the word in the sense that only sounds found in mother nature are "natural"?

 

In his 2013 article, "What should nature sound like", O'Schwarz writes, "[t]he sounds of nature are ... the sounds that have the best mental impact on me, more than any music, and music would ruin it", where mental impact was described as "elevating the soul" and liberat[ing] the whole body." This is generally true of how most people tend to perceive nature. Generally the more pleasant and soothing sounds are considered to be natural, and unpleasant sounds or "noise" is considered to be manmade and unnatural. Additionally, some argue that music inhibits the ability to pay closer attention to surroundings, essentially that non-natural sounds drown out natural sounds.

 

An interesting application of "natural sounds" is in tourism and deals with regulation, as "different modes of engagement with nature sites ... pose different demands to the sensory regulation of space. Nature users care about these experiences, and prefer sonic ambiences that are compatible with their modes of engagement" (O'Schwarz). Different people also have different sonic preferences, so this might lead to conflict in regulation and policy of what the ideal soundscape should sound like. This is relevant to the "nature sounds" of freshwater, as there is generally a lack of regulation in aquatic sound. Should aquatic sound be regulated, as to avoid harmful or negative impact on other beings (not necessarily human)?

 

Case Studies

The case studies involved with this portion include a sampling of different types of aquatic environments recorded in different locations, such as various settings in Puerto Rico and in the local North Carolina region. Even within a location, recordings are varied in order to capture the multitude of different aspects that give aquatic soundscapes their distinctive nature and beauty. The trickling of water in a stream and the powerful fall of water in a waterfall are both formed by the same essentials, yet are so different in terms of sonic environment. Each case study will be analyzed, after which I will write about natural soundscapes, what they sound like above and below the surface of the water, and how we as humans interact with this soundscape. During this, I will seek answers to the following quesitons, using recordings and their edits to aid me: What does "nature" or the "natural sounds" sound like, once the external interference is removed? Do natural sounds inhibit us from hearing other natural sounds, and if so, are they "noise"? What does an aquatic soundscape sound like underwater, how does this contrast from how it sounds above the surface, and how does the underwater soundscape actually sound like compared to most people's ideas? How are freshwater soundscapes impacted by external forces, and how does this affect the soundscape?

 

Findings:

After performing all of the case studies and accompanied analyses, it can be said that while the external soundscape might sound very diverse, the aquatic soundscape sounds very similar in terms of sound types present, and this might be due to the medium itself – sound propagates less quickly and scatters more quickly in water, leading to very localized sounds. The aquatic soundscapes do not sound as we would expect, as what we imagine as the aquatic soundscape is based on our perception of our experiences above the water. Because of this, regulation of aquatic soundscape is probably not a priority issue. Additionally, it is not possible to replicate nature sounds. What does nature sound like anyways? The overall soundscapes also vary quite noticeably depending on the circumstances. While these generally do not affect the underwater sounds much, as the water seems to act as a sonic shield, insulating the aquatic soundscape from external ones, they vary the overall soundscape. When these two are then put together to get a more unified and holistic representation of the total sonic "mesh" at a particular location, the overall soundscape can be very different, with the hydrophones adding a nice touch to the recordings themselves.

 

Citations:

O'Schwarz, C. 2013. "What Should Nature Sound Like?: techniques of engagement with nature sites and sonic preferences of Israeli visitors". Annals of Tourism Research 42: 382–401.

 

Ren, Huiying, Michele B. Halvorsen, Zhiqun Daniel Deng, and Thomas J. Carlson. 2012. "Aquatic Acoustic Metrics Interface Utility for Underwater Sound Monitoring and Analysis." Sensors 12 (6): 7438-7450.

 

Sueur, Jerome, David Mackie, and James F. C. Windmill. 2011. "So Small, So Loud: Extremely High Sound Pressure Level from a Pygmy Aquatic Insect (Corixidae, Micronectinae)". PLoS ONE 6 (6): 1-6.