Species similar to Hardhead

Tufted Duck

Aythya fuligula

Ring-necked Duck

Aythya collaris

Lesser Scaup

Aythya affinis

Common Pochard

Aythya ferina

Greater Scaup

Aythya marila

Redhead

Aythya americana

Canvasback

Aythya valisineria

Ferruginous Duck

Aythya nyroca

New Zealand Scaup

Aythya novaeseelandiae

Baer's Pochard

Aythya baeri

Madagascar Pochard

Aythya innotata