Churnet Valley Wildlife : Dippers, fungi and dry-stone-walls - a walk from Oakamoor, through Cotton Dell, Whiston and back.

Cotton Dell, where two Dippers were seen (see text below).

Dipper.

Dippers are a resident species that feed on a range of freshwater animals including invertebrates such as caddis fly larvae and even small fish. Creatures such as these can only exist in oxygen-rich waters that range from mildly acid to calcium rich and so water quality is an important factor determining the geographical range of Dippers. The presence of two Dippers on the stream in Cotton Dell suggests the water is of good quality, and it certainly looked much clearer than do many of the streams and rivers in the Churnet Valley.

Dippers formerly occupied many more rivers and streams that they do at present. Water pollution has led to a reduction in food supply and hence the habitat available to the birds. The water pollution is from two sources. In some water courses, the water has become acidified due to acid rain (this was and is caused by the extensive planting of conifer plantations in the 1970s and 1980s and aerial sulphur dioxide from vehicle exhausts and industrial sources). In addition some streams and rivers are polluted by farm effluents, which caused a depletion in oxygen levels in the water (because the nutrients in the effluent feeds microbes such as cyanobacteria which in turn use up much of the available oxygen).

Dippers remain in their territories pretty much all year round as they are able to survive all but the harshest of winters. They start to breed as early as February so winter is a good time to look and listen for them. If you are persistent you may be fortunate enough to hear the lovely warble of a Dipper as it perches on a stone in one of our local streams.