The European Dipper has a UK population of less than 7000 pairs. Their population has undergone a substantial decline in recent decades (nearly 40% since 1995), and the species is now AMBER rated on the Birds of Conservation Concern list.
UK Dippers are ecologically reliant on freshwater rivers, and normally associated with more upland areas, where landscape gradients result in faster river flow and higher levels of water oxygenation.
The species is extremely sensitive to changes in water pH (mediated through impacts on invertebrate communities), and it does not tolerate highly acidic waters. It is thus an extremely useful and reliable indicator species for the ecological impacts of human activities and environmental change.
The ongoing and long-term population declines have been linked to both pollution of the UK’s river systems and increased acidification. The latter problem is being exacerbated and accelerated by climate change, mediated through CO2 dissolving into water as carbonic acid.
This process occurs more readily and rapidly during periods of hot weather, and is a known impact of longer and hotter summers. This has been coupled with atmospheric pollution that increases both sulphur and nitric oxide deposition in freshwater systems, and these also result in further acidification.
