Shadows, undercurrents and the aliveness machines

Introduction: resident in expanded ecologies The River Torridge catchment (Devon, South West UK) is a picturesque and serene wooded river valley setting, with a largely undeveloped estuary coastal zone. It has been selected as one of six sites in England to be designated a UNESCO Biosphere Reserve. Beneath this seemingly idyllic surface however, there exist some serious ecological-health issues that are being actively addressed by the reserve’s operational staff. Key indicators of declining health include the freshwater pearl-mussel, whose habitat lies within the gravel-beds of the river. This shellfish species is rare in the UK, and noted for its longevity and high sensitivity to water quality. An individual’s age can be determined by counting the annual growth rings on the shell. In the River Torridge, the local population has not reproduced for over 50 years. Thus, unless the water quality and habitat conditions can become conducive to reproduction again, the concern is that the freshwater mussel will become locally extinct.