Order: Anseriformes
Family: Anatidae
Aythya marilla
Greater Scaup

Size: 42-51 cm
Habitat
They live in marshes, lagoons, dams, ponds, pools, and also in the sea.
They do not nest (breed) in Spain. They are a regular but scarce hibernating species.
Distribution: North-America, Europe and Asia. They can be seen in the lagoons of the centre of the Iberian Peninsula, as well as in some areas in the south-east, particularly in Doñana. Even though they are sparse, they can be seen in deep lagoons during winter. 
They are included in the National List of Endangered Species, and their conservation status is ‘Special Interest’.