Ferruginous Duck, Aythya nyroca, is a species of diving duck found in wetland, river and lake and marine inlet and transitional water ecosystems. It is breeding across the Southern, South-Eastern and Eastern Europe. The species shows a strong preference for fresh standing water. It frequents shallow pools and marshes with abundant emergent, floating and shoreline vegetation such as reeds, willows and alders. In the breeding season, it also frequents saline, brackish or alkaline lakes in some areas, e.g. in Hungary, also well-managed fishponds are important summer habitat locally. Outside breeding season, it may frequent larger lakes, including inland seas, reservoirs, lagoons and coastal marshes (European Red List 2015).

Aythya nyroca has a breeding population size of 13100-20700 pairs and a breeding range size of 182000 square kilometres in the EU27. The breeding population trend in the EU27 is Unknown in the short term and Unknown in the long term. Aythya nyroca has a winter population size of 570-1800 individuals in the EU27. The winter population trend in the EU27 is Increasing in the short term and Increasing in the long term.

The EU population status for Aythya nyroca is Unknown, as the data reported were not sufficient to assess the population status of the species.