Oberlin Natural Spaces Soundscape Study:
Considering Anthrophonic Noise in "Wild" Spaces
By: Katherine Karson, Cate Lytle and Heidi Yarger
Our soundscape study centers on human activity and intervention in the natural landscapes of Oberlin. The Arboretum and Plum Creek Corridor are areas that are designated as “natural”, while George Jones Farm contains ecological phenomena within it. We explored the three locations during various times of day and under different conditions to investigate the similarities and differences in their soundscapes. Mainly, we focused on the presence of anthrophonic sounds in these natural spaces, and the concept of human-sourced noise and its interaction with the natural biophony. While this is not strictly a study of one soundscape, it is the study of several locations that are more rural, and therefore presents the opportunity to question and analyze patterns of sonic characteristics within the Oberlin soundscape as a whole. Specifically, we found it difficult, if not completely impossible, to separate the distant anthrophony from biophony within these natural spaces.
Location 1: George Jones Farm
George Jones Farm is a 70-acre farm and nature preserve. It is built with a permaculture framework in mind, so while there are what one might consider typical fields that have been plowed for crop cultivation, most of the farm is covered in meadows and dense forest. The path leading up the beehives runs between a small, man-made pond, and a dense forest/shrub area. The amount of “wild” space coupled with the farm’s organic practices (no pesticide usage, for example) provides habitat for many insects, birds, and animals. There are two beehives, both located atop a small hill that is surrounded at the moment by goldenrod plants.
Recordings were taken on separate days during different time periods, meaning that weather and time-period played a role in what was recorded. For example, I could only record the beehives on sunny days because bees do not leave the hive when it is raining, nor do they leave at nighttime. The distance of the path to the apiary itself from the roadway, as well a its position on the farm itself, made for very little anthrophony (human-sourced sound). In fact, the only human-made sounds audible in my recordings are those of my own footsteps as I made my way through the tall grasses of the meadow.
Throughout all of the recordings, crickets are audible—denoting the cricket chorus as a keynote sound (a sound that is consistently in the background sound environment). One recording was taken during a rainstorm by the edge of the forest. In that recording, the raindrops hitting the microphone are a sound signal of that moment in time—the transition from summer into fall as the recording was taken right after the fall equinox (track 2). In the recordings of the bees themselves, not much is audible outside of the bees buzzing around the microphone, occasionally bouncing off its surface. Here, the sound signal, or particular sound of the moment, is the buzz of the bee, which, even to someone who hasn’t visited the hives, communicates the chaotic and lively nature of the soundscape (track 1).
Currently, the hives are being attacked by wasps and are in a state of emergency, this is sonically reflected in the volume of their buzzing as well as the “bouncing” off of the microphone—bees bounce off of objects as an act of warning to intruders that they are ready to sting. The aggression of the bee recording contrasts the recording of the forest during a rainstorm. In the latter recording, the sound of rain is consistent without much variation, while in the former, the bees as they fly back and forth from the entrance of the hive (which is where the microphone was set) creates a variable sonic experience depending on how close bees are to the microphone as well as the speed that they are flying by.
Location 2: Plum Creek Corridor
The next area that we investigated was the "Plum Creek Riparian Corridor Research and Maintenance Site". A riparian corridor is the land that is situated next to a body of water and one of its many uses is that it acts as a buffer and helps reduce flooding. The Oberlin Public Works Department’s Riparian Corridor Restoration Project believes that “improving the buffers in the Plum Creek riparian corridor will help improve the overall health, functionality and beauty of the Plum Creek corridor.” They are working on this by suppressing the growth of invasive plants such as Japanese, Knotweed and Multiflora Rosa, and have germinated the area with plants such as native shrubs and trees.
While the existence of a restoration project was set out with good intentions in preserving the overall health of the ecosystem, the human intervention must have affected the soundscape in ways that may go unnoticed. We compared rush hour on Thursday afternoon (22nd September at 4pm) and Friday evening (17th September at 8pm) and the results were astonishing.
It was very surprising that while we expected heavier anthrophony on Thursday afternoon due to rush hour, on Friday evening there were more hi-fi sounds that reached the soundscape from a community event in downtown Oberlin: we found an earwitness that affirmed fireworks for the Eid celebration at Lewis House so that could be one plausible explanation. So while there was more immediate anthrophony affecting the soundscape during the day, the sounds in the evening were affecting the soundscape from a much greater distance. The latter is more dangerous because it implies that the producers of the sound are unaware of the distance their sound can travel and therefore cannot see the extent to which they are potentially affecting or not affecting the health of soundscapes.
Furthermore we can hear the difference in the density of the soundscape during the day and at night, when there is much more perceivable biophony. It is difficult to attribute the difference of biophony solely to the influence of anthrophony because there was an equal amount of traffic in the evening as there was during the day. It would be interesting to consider how the soundscape changes when there are people directly working in the corridor and see to what extent that affects the biophony of the ecosystem. Even though the evening soundscape suggests a much healthier environment when there less immediate anthrophony affecting the area, the corridor is still situated within a greater urban soundscape with multiple houses situated on either side which would imply that there is a certain level of adaptation already having been made by the animals.
Location 3: Oberlin Arboretum
The third location we explored for our soundscape study was the “Arb” - Oberlin’s Arboretum, a 17-acre nature preserve located at the southernmost point of the campus. This area could be considered one of the most “wild” spaces of Oberlin, as it has many natural pathways, two large ponds, densely wooded areas with a flowing creek, and clearings of tall grasses and weeds. Because of this diversity of landscapes within the Arb, I focused the recordings around three areas. These included a wooded pathway that runs on the outermost side of the reservoir pond and leads to a more wooded area, a sloping cleared grass hill, and a wide flat field thick with tall grasses and goldenrod. I visited these locations on two separate dates and times, midday on Saturday, September 17th at 12pm and at sunset on Monday, September 19th at 6pm. In terms of weather conditions, Saturday was a warmer, damp and cloudy day with shifting periods of rain, while Monday was cooler and dry with frequent gusts of strong wind.
Solely based on these climatic factors, I could already hear a difference in the acoustic texture of the soundscape. The Saturday recordings have a more compact, reverberant quality to them, likely influenced by the humidity of the day and cloudy conditions. On the forest path, the diverse biophony of the soundscape included the keynote of the fast chirps and trills of crickets mixing with the deeper underlying buzz of cicadas. There were several types of birds that called out periodically, and their calls bounced and echoed around the forest. I also came across a squirrel with a fast, sharp-pitched chattering (track 6). The soundscape shifted as I left the forest and moved to the hill and clearing, where the open space made the similar sounds more open and distant. The crickets hiding in the tall grasses became the keynote of these spaces, and while bird calls were still present, they were further apart in frequency. Additionally, buzzing bees and wasps that hovered around the goldenrod.
The muddy conditions in the Arb’s spaces on Saturday meant few others were exploring its paths, so most anthrophonic noise in close range, besides my own footsteps and rustling, was absent in the locations I visited.
However, I quickly realized that these “wild” spaces were not free from the distant anthrophonic noises of downtown Oberlin. In the recordings of each of the three locations I visited on Saturday, there was always some human-centered sound present that filled the spaces (and sometimes masked) the acoustic patterns of the Arb’s biophony. In the hi-fi nature of the Arb’s soundscape, the low ambient noise made these “urban” sounds very distinct in and often obtrusive to the sound cycles of the habitat. For example, the rushing jets of passing airplanes were present in both my Saturday and Monday recordings, and this low frequency noise often altered and masked the cricket, cicada and bird calls (track 5).
Specifically, on my Monday visit at sunset to the three locations, there was considerable external anthrophonic noise that competed with the chorus of crickets, birds and other insects. I heard the constant whining whir of a leafblower’s engine, the pervasive bark of dogs, and the deep rumbling rush and honking of passing cars (tracks 7 and 8). At one point the loud echoing siren of an ambulance cut through the soundscape unexpectedly, and the birds and insects seemed to increase the rate and sound level of their calls in an alarmed response (track 9).
By recording three separate locations, George Jones Farm, the Plum Creek Corridor and the Arb, we were able to consider how time and climate affects the soundscape of a given space, specifically in relation to human-sourced sounds. While we do not go as far as to consider these anthrophonic sounds “noise pollution” or sounds that detract from the soundscape in our study, it is hard not to consider them as an interference. There is an expectation for “natural” spaces such as the Arb to be tranquil places free from the noise of the automated world. The echoing drawl of a leaf blower or the bark of a neighborhood dog has a definite presence against the ambience of cricket and bird calls. Even spaces where there is little anthrophony are subject to sound interference of other sorts. The beehives at George Jones Farm, in their current state of distress, sound chaotic and have an increased volume compared to unstressed hive conditions, much like the increased sonic reaction of the Arb's organisms at the passing ambulance siren. The soundscape of a given space is constantly in a state of flux - factors such as weather, human activity, and time of day all play a role in the patterns of sonic activity at a given moment. Rather than classifying such sonic shifts as solely “good” or “bad,” we wish to instead consider each sound as a way to interact with and gain information from our environments.
An ambulance's siren cuts through the biophony of the evening chorus at the Arb. You can see on the spectrogram the rise and fall of the siren's pitch, in comparison to the steady hum of crickets and periodic sharp chirp of a bird, and cicada buzz in the background. Notice how the frequency and intensity of the bird call increases around the 42 second mark, likely as an alarmed response to the loud siren.
A particularly intense period of bee activity starts around the 12 second mark of track 1. The bees fast-paced buzzing wings dominate the soundscape as the clear keynote, although the higher pitched chirp of crickets can be heard moderately in the background. Each time a bee bumps the microphone the buzz sound increases dramatically.
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