The BTO winter atlas showed that Pochards were noted in 10km squares containing suitable fresh water sites 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 95 birds seen in a day.
Up to 462 were recorded at Bosherston, the principal locality for this species.
Graham Rees