Justification This species has an extremely large range, and hence does not approach the thresholds for Vulnerable under the range size criterion (Extent of Occurrence <20,000 km2 combined with a declining or fluctuating range size, habitat extent/quality, or population size and a small number of locations or severe fragmentation). The population trend appears to be increasing, and hence the species does not approach the thresholds for Vulnerable under the population trend criterion (>30% decline over ten years or three generations). The population size is very large, and hence does not approach the thresholds for Vulnerable under the population size criterion (<10,000 mature individuals with a continuing decline estimated to be >10% in ten years or three generations, or with a specified population structure). For these reasons the species is evaluated as Least Concern.

Family/Sub-family Anatidae

Species name author (Linnaeus, 1758)

Taxonomic source(s) AERC TAC (2003), Cramp and Simmons (1977-1994), Dowsett and Forbes-Watson (1993), Sibley and Monroe (1990, 1993)

Population estimate

Population trend

Range estimate (breeding/resident)

Country endemic?

580,000 - 710,000

unset

9,390,000 km²

No

Important Bird Areas Click here to view map showing IBAs where species is recorded and triggers any of the IBA criteria.

Ecology: Behaviour Most populations of this species are migratory (although European populations are largely sedentary) and undertake extensive moult migrations to favoured moulting sites after breeding¹ (Asiatic breeding populations may also moult near their breeding grounds)². The species breeds in single pairs or small groups^{1, 4}, non-breeders usually remaining in flocks throughout the year². After breeding (between July and October) the species moults and becomes flightless for 25-31 days², during which it is highly gregarious³ and may aggregate into large flocks of up to 100,000 individuals or more^{2, 1}. Habitat The species shows a preference for saline habitats and frequents mudflats¹ and muddy or sandy³ estuaries^{1, 3} in coastal regions, and occurs inland on saline and brackish lakes in steppe or semi-desert³. Asiatic populations also occupy freshwater rivers or marshes² and other populations utilise freshwater habitats on migration⁴. Diet Its diet consists predominantly of salt-water molluscs (e.g. Hydrobia spp.) as well as other aquatic invertebrates (e.g. insects, crustaceans and worms), small fish, fish spawn and plant material¹ (e.g. algae, seeds and agricultural grain)². Breeding site The nest is commonly positioned in a tree-hollow¹ up to 8 m above the ground² or in a mammal burrow (e.g. of European rabbit Oryctolagus cuniculus)^{1, 2}. Rarely nests may also be placed in the open or in dense vegetation up to 1 km from water^{2, 3}. The species will also nest in artificial nest-boxes². Management information 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 diversity⁶. In the outer archipelago of south-west Finland experimental removal (extermination) of the nest predator American mink Neovison vison resulted in an increase in the breeding density of this species⁵.

Threats The species is threatened by habitat loss as a result of tidal barrage schemes in Europe^{2, 8}. It also suffers predation from American mink Neovison vison on islands⁵ and is susceptible to avian influenza so may be threatened by future outbreaks of the virus⁷. Utilisation The species is hunted for commercial and recreational purposes in Iran⁹, and its eggs used to be (and possibly still are) harvested in Iceland¹⁰.

References 1. del Hoyo et al. (1992). 2. Kear (2005a). 3. Madge and Burn (1988). 4. Flint et al. (1984). 5. Nordstrom et al. (2002). 6. Bregnballe et al. (2004). 7. Melville and Shortridge (2006). 8. Burton (2006). 9. Balmaki and Barati (2006). 10. Gudmundsson (1979).

Further web sources of information

Detailed species account from Birds in Europe: population estimates, trends and conservation status (BirdLife International 2004)

Text account compilers Stuart Butchart (BirdLife International), Jonathan Ekstrom (BirdLife International), Lucy Malpas (BirdLife International)

IUCN Red List evaluators Jeremy Bird (BirdLife International), Stuart Butchart (BirdLife International)

Recommended citation BirdLife International (2009) Species factsheet: Tadorna tadorna. Downloaded from http://www.birdlife.org on 10/2/2010

This information is based upon, and updates, the information published in BirdLife International (2000) Threatened birds of the world. Barcelona and Cambridge, UK: Lynx Edicions and BirdLife International, BirdLife International (2004) Threatened birds of the world 2004 CD-ROM and BirdLife International (2008) Threatened birds of the world 2008 CD-ROM. These sources provide the information for species accounts for the birds on the IUCN Red List.

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