|Common Pochard (Aythya ferina)
(aka Pochard, Eurasian Pochard)
The Pochard forms a superspecies with the Canvasback (Aythya valisineria) of North America although it looks superficially more like the Redhead (Aythya americana) also of North America but which has a yellow iris rather than a red one in the male.
The Pochard is present throughout the year in central and north-west Europe but more northerly breeding populations in Europe and Asia winter in southern Europe, Africa, India, southeast Asia and Japan.
|Although a relatively scarce breeder in Britain, it is fairly widespread during winter though in small numbers in many areas.
Valerie Thom mentions the fascinating decline and fall of the wintering Pochard flock at Duddingston Loch, Edinburgh. Average peak numbers reported rose from 2,500 in the early 1960's to about 6,000 in the early 1970's. The population slumped in the winter of 1978/79 to an average peak of 200. The Lothian Bird Report 1999 gives a peak count of 22 for Duddingston.
The explanation for this is that the Duddingston flock did not feed on the Loch but were found to feed on the nearby Firth of Forth particularly around the sewage outfalls. Early in 1978 Edinburgh's new sewage disposal plant came into operation.
There is an illustration in HBW, Volume 1, Page 614.