Tadorna tadorna -- (Linnaeus, 1758) ANIMALIA -- CHORDATA -- AVES -- ANSERIFORMES -- ANATIDAE Common names: Common Shelduck; Shelduck; Tadorne de Belon European Red List Assessment European Red List Status LC -- Least Concern, (IUCN version 3.1) Assessment Information Year published: 2015 Date assessed: 2015-03-31 Assessor(s): BirdLife International Reviewer(s): Symes, A. Compiler(s): Ashpole, J., Burfield, I., Ieronymidou, C., Pople, R., Wheatley, H. & Wright, L. Assessment Rationale European regional assessment: Least Concern (LC) EU27 regional assessment: Least Concern (LC) In Europe this species has an extremely large range, and hence does not approach the thresholds for Vulnerable under the range size criterion (Extent of Occurrence 10% in ten years or three generations, or with a specified population structure). 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). For these reasons the species is evaluated as Least Concern in Europe. Within the EU27 this species has a very large range, and hence does not approach the thresholds for Vulnerable under the range size criterion (Extent of Occurrence 10% in ten years or three generations, or with a specified population structure). 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). For these reasons the species is evaluated as Least Concern in the EU27. Occurrence Countries/Territories of Occurrence Native: Albania; Armenia; Austria; Azerbaijan; Belarus; Belgium; Bosnia and Herzegovina; Bulgaria; Croatia; Cyprus; Czech Republic; Denmark; Estonia; Finland; France; Germany; Greece; Hungary; Iceland; Ireland, Rep. of; Italy; Latvia; Lithuania; Macedonia, the former Yugoslav Republic of; Malta; Moldova; Montenegro; Netherlands; Norway; Poland; Portugal; Romania; Russian Federation; Serbia; Slovakia; Slovenia; Spain; Sweden; Switzerland; Turkey; Ukraine; United Kingdom Vagrant: Liechtenstein; Luxembourg; Canary Is. (to ES); Gibraltar (to UK) Population The European population is estimated at 50,800-68,900 pairs, which equates to 102,000-138,000 mature individuals. The population in the EU27 is estimated at 40,800-53,900 pairs, which equates to 81,700-108,000 mature individuals. For details of national estimates, see Supplementary PDF. Trend In Europe and the EU27 the population size is estimated to be increasing. For details of national estimates, see Supplementary PDF. Habitats and Ecology The species shows a preference for saline habitats and frequents mudflats (Carboneras and Kirwan 2014) and muddy or sandy estuaries in coastal regions, and occurs inland on saline and brackish lakes in steppe or semi- desert (Madge and Burn 1988). Breeding begins in April and May in single pairs or small groups. The nest is commonly positioned in a tree-hollow (Carboneras and Kirwan 2014) up to 8 m above the ground (Kear 2005) or in a mammal burrow (Kear 2005, Carboneras and Kirwan 2014). Rarely nests may also be placed in the open or in dense vegetation up to 1 km from water (Madge and Burn 1988, Kear 2005). The species will also nest in artificial nest boxes (Kear 2005). Its diet consists predominantly of saltwater molluscs (e.g. Hydrobia spp.) as well as other aquatic invertebrates (e.g. insects, crustaceans and worms), small fish, fish spawn and plant material. Most populations of this species are migratory (although European populations are largely sedentary) and undertake extensive moult migrations to favoured moulting sites after breeding (Carboneras and Kirwan 2014). Habitats & Altitude Habitat (level 1 - level 2) Importance Occurrence Marine Intertidal - Mud Flats and Salt Flats major breeding Marine Intertidal - Mud Flats and Salt Flats major non-breeding Marine Neritic - Estuaries major breeding Marine Neritic - Estuaries major non-breeding Wetlands (inland) - Permanent Freshwater Lakes (over ha) suitable breeding Wetlands (inland) - Permanent Freshwater Lakes (over ha) suitable non-breeding Wetlands (inland) - Permanent Saline, Brackish or Alkaline Lakes suitable breeding Wetlands (inland) - Permanent Saline, Brackish or Alkaline Lakes suitable non-breeding Altitude Occasional altitudinal limits Threats The species is threatened by habitat loss as a result of tidal barrage schemes in Europe (Kear 2005, Burton 2006). It also suffers predation from American Mink (Neovison vison) on islands (Nordstrom et al. 2002) and is susceptible to avian influenza so may be threatened by future outbreaks of the virus (Melville and Shortridge 2006). Its eggs used to be (and possibly still are) harvested in Iceland (Gudmundsson 1979). Threats & Impacts Threat (level 1) Threat (level 2) Impact and Stresses Biological resource Hunting & trapping Timing Scope Severity Impact use terrestrial animals Ongoing Minority (<50%) Negligible declines Low Impact (intentional use - species is the target) Stresses Species mortality Energy production Renewable energy Timing Scope Severity Impact & mining Ongoing Minority (<50%) Slow, Significant Low Impact Declines Stresses Ecosystem conversion Invasive and other American Mink Timing Scope Severity Impact problematic (Neovison vison) Ongoing Minority (<50%) Negligible declines Low Impact species, genes & diseases Stresses Species mortality Invasive and other Avian Influenza Timing Scope Severity Impact problematic Virus (H subtype) Past, Likely to Majority (50-90%) Rapid Declines Past Impact species, genes & Return diseases Stresses Species mortality Conservation Conservation Actions Underway CMS Appendix II. Bern Convention Appendix II. There are currently no known conservation measures for this species. Conservation Actions Proposed Predator control at breeding sites would help this species locally and the construction of artificial caves may increase local breeding pair numbers (HELCOM 2013). Important areas for this species need to be protected. Environmental impact assessments for new tidal energy schemes should be undertaken. Bibliography Burton, N.H.K. 2006. The impact of the Cardiff Bay barrage on wintering waterbirds. In: Boere, G., Galbraith, C. and Stroud, D. (ed.), Waterbirds around the world, pp. 805. The Stationary Office, Edinburgh, UK. Carboneras, C. and Kirwan, G.M. 2014. Common Shelduck (Tadorna tadorna). In: del Hoyo, J., Elliott, A., Sargatal, J., Christie, D.A. and de Juana, E. (eds.) 2014. Handbook of the Birds of the World Alive. Lynx Edicions, Barcelona. (retrieved from http://www.hbw.com/node/52839 on 3 March 2015). Gudmundsson, F. 1979. The past status and exploitation of the Myvatn waterfowl populations. Oikos 32(1-2): 232-249. HELCOM (2013). Species Information Sheet – Tadorna tadorna. HELCOM Red List Bird Expert Group Kear, J. 2005. Ducks, geese and swans volume 1: general chapters; species accounts (Anhima to Salvadorina). Oxford University Press, Oxford, U.K. Madge, S. and Burn, H. 1988. Wildfowl. Christopher Helm, London. Melville, D.S. and Shortridge, K.F. 2006. Migratory waterbirds and avian influenza in the East Asian- Australasian Flyway with particular reference to the 2003-2004 H5N1 outbreak. In: Boere, G., Galbraith, C. and Stroud, D. (ed.), Waterbirds around the world, pp. 432-438. The Stationary Office, Edinburgh, UK. Nordström, M., Högmander, J., Nummelin, J., Laine, J., Laanetu, N. and Korpimäki, E. 2002. Variable responses of waterfowl breeding populations to long-term removal of introduced American mink. Ecography 25: 385-394. Map (see overleaf) .