Shelduck. Historical artwork of a shelduck (Tadorna tadorna). This duck inhabits coastal areas throughout much of Europe, Asia and north Africa. It feeds on marine invertebrates such as shellfish and crustaceans. Birds from the northernmost part of the range travel south during the winter. It is a large duck, with a maximum length of around 70 centimetres. This artwork was drawn by Archibald Thorburn (1860-1935).