Table 1.

Diet characteristics

Species	Protection of species	Diet
Common goldeneye Bucephala clangula	Strict legal protection in Poland	Almost entirely animal food, mostly mollusks (Bivalvia), crustaceans, water insects (e.g., caddis larvae), small fish and amphibiansa
Tufted duck Aythya fuligula	Hunting season in Poland: 15 August–21 December	Usually animal food (82–97%), mostly mollusks. Small share of plants in the diet (3–18)b
Common pochard Aythya ferina	Hunting season in Poland: 15 August–21 December	Mostly plant food, especially in spring and summer, and small water animals in autumn and winter—usually insect larvae, and to a smaller extent snails and clamsc
Greater scaup Aythya marila	Strict legal protection in Poland	Mostly mollusks (98%). Small share of plant food in the diet (2%)a

^aStempniewicz and Meissner (1999)

^bOlney (1963)

^cOlney (1968)