The species may breed on low-lying Arctic coasts and estuaries but is more common on freshwater pools, lakes or rivers in the Arctic tundra (Billerman et al. 2020). Optimum habitats include lakes where the water does not completely freeze, which have dependable supplies of fish, highly convoluted shorelines and aquatic vegetation providing habitats for fish and sites for nesting and brood rearing (Earnst et al. 2006). Outside of the breeding season the species inhabits inshore waters (Billerman et al. 2020), fjords with muddy substrates (Byrkjedal et al. 2000) and inlets (Snow and Perrins 1998) along sheltered coasts. It breeds from early June (largely depending upon the timing of the spring thaw) in solitary pairs. The nest is a heap of plant matter or turf built near the water's edge, usually on the shore of a clear-water lake with good visibility over surrounding areas. Clutch size is two. Its diet is little known but may consist predominantly of fish as well as crustaceans, molluscs and marine annelids. This species is fully migratory. After breeding it travels southwards and towards the coast (Billerman et al. 2020) to its wintering grounds, where it is present between October and May (Snow and Perrins 1998).

Although the generation length for both EU and Europe regional assessments were calculated using the same methodology, new information arriving after the EU assessments were undertaken gave rise to an update in the generation lengths. This new information was then used for the Europe level assessments giving rise to a difference between the generation lengths used for the EU and Europe regions.

In Europe, the species occurs in winter at sea, off the coasts of Norway.

The species has not been recorded in the breeding season in Europe (Russia) since 2005.

Conservation Actions Underway
Western Palearctic population is CMS Appendix II. There are no known conservation measures in place.

Conservation Actions Proposed
Update the current population estimate and establish a monitoring programme to elucidate trends. Assess current levels of harvest and initiate control measures should they be unsustainable. Assess comparative ecology and possible impact of climate change.