In the coming days the waters of the River Dee, rising in the Cairngorms and flowing east to reach the North Sea at Aberdeen, will burst into life. This neighbor of the River Spey (our namesake) stretches 86 miles across the Highlands of Scotland and is another crucial stronghold of our beloved pearl mussels. Conditions over these next few days, however, are critical. Just once each year the mussels collectively release millions of tiny larvae into the water. The longevity of the threatened species is pinned to these tiny baby mussels, for they face the most extraordinary odds. In order to survive as individuals (and collectively as a population), these larvae must happen upon the gills of a passing fish and anchor themselves to the nutrient-rich surroundings. Fewer than one in four million make it. But thankfully, progress is being made to help turn the tide in favor of this cornerstone species.
As part of the £3.5m Pearls in Peril project, which congruously supports work within the River Spey and others throughout the British Isles, a transformation of the River Dee is underway. A bold plan of terra-rejuvenation, this project seeks to restore the river to its natural course. For too long, man has constructed artificial banks and barriers, funneled water away through man-made channels, and influenced the natural environment to better suit human activity. The cruel irony of all this “planning” is that the river has suffered dramatically – and humans are reliant on the health of the ecosystem around us. Populations of freshwater mussels, for instance, have been halved in the last decade, or wiped out entirely from rivers across Scotland, England and Wales. The meandering shallows, cascades and pools that suit the lifecycle of the mussels are all but disappearing.
Each mussel filters daily the equivalent of 50 liters of water (providing clean drinking water to nearly 200,000 Aberdonians), so it is most disheartening when intentionally-placed boulders, railway sleepers, and junk cars are creating a deleterious blockade to the smooth course of the river. Dredging these hazards is most certainly a step in the right direction, as is replanting native trees along the river that provide cooling shade to the warm waters and prevent erosion. Spey salutes this project and the scientists and environmentalists that are working to reinstate balance within the environment. Let the river do what the river wants to do. Sage advice for the future health of the planet.
For more on the River Dee project, continue reading this recent article in The Guardian newspaper: River Dee’s Pearl Mussels Get a Helping Hand – or Gill.
Image: Jackie Webley, Pearls in Peril project manager for Scottish Natural Heritage, at work in the River Dee. Credit: Martin Hunter for The Observer.