The scuffle of fallen leaves swishing in mini-whirlwinds along the gravel path and the hollow beat of a swan’s wings as it lifts from the river.
The shrill call of a heron on the far bank mingles with the bellow of stags from a nearby deer farm. Crows craw in among the branches and the rain starts to fall at first with a few noisy plops onto the river before rising into a thrum.
Despite this natural aural symphony, many of those walking along the riverbank have their heads encased in a helmet of headphones. Somehow it seems that, for some, walking has become a necessary evil, best undertaken with some distraction until the requisite number of steps have been registered on their wrist step-counter.
Or maybe they are simply trying to cut out the underlying hum of modern civilization.
For despite the bird songs, and sounds of the rutting deer, the wind shifting through the browning autumn leaves and drum of the rain, there is another background noise.
The furthest part of my walk is a couple of miles from the nearest town and is well away from the main roads, sheltered by woodland and drumlins. Yet there is still a constant drone, the collective noise of cars and lorries and other aural detritus from the nearby urban sprawl.
Occasionally a car with some contraption attached to its exhaust will rip into the soundscape – like a an embarrassing drawn-out fart.
The ancient Greek philosopher Plato used the allegory of a group of chained prisoners sitting in cave and facing a wall to illustrate how human perception of nature and the wider cosmos has become dulled.
Behind them is a fire and all that they can see is the shadows cast by the glowing flames which they come to assume is reality. But when one of the prisoners escape and emerges from the cave into daylight he comes to realise that the mere flickering shadows on the wall are only a fragment of the totality of reality which exists outside the cave.
In the same way, particularly for those of us who live in towns and cities, we have become imprisoned by a collective tinnitus, a constant industrial drone that has become an aural backdrop to our lives.
And even for those who live in the countryside, how many ever turn off the television or radio, or music player or whatever?
In the same way that light pollution has obscured our skies and blinded us to the magnificence of the planets and stars and sweep of the Milky Way on a clear night, noise pollution is deafening us to the sounds of nature.
During Earth Hour in March this year, millions of people across the globe switched off their lights in a largely symbolic act to highlight how much energy the planet could save by a simple collective act.
Maybe something similar could be done if we switched off all our car engines, turned off the TVs and radios and music players, even just for five minutes, to show how rich our natural aural landscape is.
