Sunday
Sep182011
Gadwall - 1980s BTO winter atlas
Sunday, September 18, 2011 at 4:01PM 
The BTO winter atlas showed that Gadwalls were present in both estuarine and fresh water 10km squares during the winters of 1981-82, 1982-82 and 1983-84.
The darker the colour, the higher the relative total count for each 10km square, the darkest blue represents over 23 birds.
Graham Rees