Behaviour In temperate regions breeding populations of this species are sedentary or dispersive, often making local movements during severe weather (Scott and Rose 1996). Other populations are fully migratory (Kear 2005) with females and juveniles leaving the breeding grounds in the western Palearctic from September and returning as early as February (Kear 2005). The species breeds between March and June (Madge and Burn 1988) in single pairs or loose groups (del Hoyo et al. 1992) although the exact timing varies with latitude (Madge and Burn 1988). While the females are incubating (Johnsgard 1978) (from mid-May) (Flint et al. 1984, Scott and Rose 1996) the males gather (Madge and Burn 1988) in small flocks and migrate to moulting areas (Flint et al. 1984) where they undergo a flightless moulting period lasting for c.4 weeks (Scott and Rose 1996) (females moult near the breeding grounds) (Flint et al. 1984). Outside of the breeding season the species can be found in small to very large flocks (Madge and Burn 1988) numbering up to several hundreds or even thousands of individuals (Snow and Perrins 1998) especially when moulting (Scott and Rose 1996), on migration (Snow and Perrins 1998) and during the winter (Kear 2005). The species may also roost both nocturnally and diurnally in communal groups when not breeding (Brown et al. 1982). Habitat The species occurs in almost every wetland type (del Hoyo et al. 1992) although it generally avoids fast-flowing, oligotrophic (del Hoyo et al. 1992, Scott and Rose 1996, Snow and Perrins 1998), deep, exposed, rough, rockbound waters and hard unvegetated areas such as rocky ground, sand dunes and artificial surfacing (Snow and Perrins 1998). It requires water less than 1 m deep for foraging (Snow and Perrins 1998) and shows a preference for freshwater habitats (Madge and Burn 1988) although it may frequent shallow brackish waters as long as they provide the cover (del Hoyo et al. 1992, Scott and Rose 1996) of submerged, floating, emergent or riparian vegetation, dense reedbeds or overhanging branches (Snow and Perrins 1998). Habitats commonly frequented include flooded swampy woodlands, seasonal floodlands (Snow and Perrins 1998), wet grassy swamps and meadows, oxbow lakes (Flint et al. 1984), open waters with mudflats, banks or spits, irrigation networks, reservoirs, ornamental waters (del Hoyo et al. 1992, Scott and Rose 1996, Snow and Perrins 1998), canals and sewage farms (Snow and Perrins 1998). During the winter the species may also be found in saline habitats along the coast (Madge and Burn 1988) where water is shallow, fairly sheltered and within site of land (Snow and Perrins 1998) (e.g. brackish lagoons [Snow and Perrins 1998], brackish estuaries [del Hoyo et al. 1992, Snow and Perrins 1998] and bays [del Hoyo et al. 1992]). Diet The species is omnivorous and opportunistic (del Hoyo et al. 1992, Snow and Perrins 1998), feeding by dabbling in water and by grazing on the land (Snow and Perrins 1998). Its diet consists of seeds and the vegetative parts of aquatic and terrestrial plants (e.g. crops) (del Hoyo et al. 1992), as well as terrestrial and aquatic invertebrates (especially in the spring and summer) such as insects, molluscs, crustaceans, worms and occasionally amphibians and fish (del Hoyo et al. 1992). Breeding site The nest is a shallow depression (Snow and Perrins 1998) or bowl of vegetation that can be situated in many different locations such as within vegetation on the ground, in natural tree cavities (del Hoyo et al. 1992) up to 10 m high (Africa) (Brown et al. 1982), under fallen dead wood, on tree stumps (Flint et al. 1984), under bushes (Brown et al. 1982) and even in abandoned nests of other species (e.g. herons or crows) (Flint et al. 1984). Nests are generally placed close to water (Kear 2005) although occasionally they may be some distance away (Madge and Burn 1988). Management information "Extensive" grazing of wetland grasslands (c.0.5 cows per hectare) was found to attract a higher abundance of the species in Hungary (Baldi et al. 2005). Studies in Danish coastal wetlands found that the spatial restriction of shore-based shooting was more successful at maintaining waterfowl population sizes than was the temporal restriction of shooting, and therefore that wildfowl reserves should incorporate shooting-free refuges that include adjacent marshland in order to ensure high waterfowl species diversity (Bregnballe et al. 2004). The species will also nest in artificial nest boxes (Brown et al. 1982, del Hoyo et al. 1992).

Conservation Actions Underway
CMS Appendix II. EU Birds Directive Annex II and III. Studies in Danish coastal wetlands found that the spatial restriction of shore-based shooting was more successful at maintaining waterfowl population sizes than was the temporal restriction of shooting, and therefore that wildfowl reserves should incorporate shooting-free refuges that include adjacent marshland in order to ensure high waterfowl species diversity (Bregnballe et al. 2004). However, no conservation measures are currently targeted at this species.

Conservation Actions Proposed
The species is not threatened and does not require any immediate conservation action but is likely to benefit from conservation measures implemented for other wetland species.