LC
Greater Scaup Aythya marila



Taxonomy

Taxonomic source(s)
AERC TAC. 2003. AERC TAC Checklist of bird taxa occurring in Western Palearctic region, 15th Draft. Available at: http://www.aerc.eu/DOCS/Bird_taxa_of_the_WP15.xls.
Cramp, S. and Simmons, K.E.L. (eds). 1977-1994. Handbook of the birds of Europe, the Middle East and Africa. The birds of the western Palearctic. Oxford University Press, Oxford.
del Hoyo, J., Collar, N.J., Christie, D.A., Elliott, A. and Fishpool, L.D.C. 2014. HBW and BirdLife International Illustrated Checklist of the Birds of the World. Volume 1: Non-passerines. Lynx Edicions BirdLife International, Barcelona, Spain and Cambridge, UK.

IUCN Red List criteria met and history
Red List criteria met
Critically Endangered Endangered Vulnerable
- - -

Red List history
Year Category Criteria
2018 Least Concern
2016 Least Concern
2012 Least Concern
2009 Least Concern
2008 Least Concern
2004 Least Concern
2000 Lower Risk/Least Concern
1994 Lower Risk/Least Concern
1988 Lower Risk/Least Concern
Species attributes

Migratory status full migrant Forest dependency does not normally occur in forest
Land-mass type Average mass -
Range

Estimate Data quality
Extent of Occurrence (breeding/resident) 46,400,000 km2 medium
Extent of Occurrence (non-breeding) 92,700,000 km2 medium
Severely fragmented? no -
Population
Estimate Data quality Derivation Year of estimate
Population size 4900000-5199999 mature individuals poor estimated 2015
Population trend decreasing - suspected -
Generation length 8.2 years - - -

Population justification: The global population is estimated to number c. 4,920,000-5,130,000 individuals (Wetlands International 2016). The breeding population in Europe is estimated at 134,000-178,000 pairs, which equates to 269,000-355,000 mature individuals (BirdLife International 2015).

Trend justification: The overall population trend is decreasing, although some populations may be stable or have unknown trends (Wetlands International 2016). This species underwent a significant population increase between 1974 and 2011 in North America (Zimpfer 2011, T. McCoy in litt. 2012). In Europe the breeding population size is estimated to be decreasing by less than 25% in 24.6 years (three grenerations) (BirdLife International 2015).


Country/territory distribution
Country/Territory Presence Origin Resident Breeding visitor Non-breeding visitor Passage migrant
Afghanistan extant vagrant
Albania extant native yes
Algeria extant vagrant
Antigua and Barbuda extant native yes
Austria extant native yes
Azerbaijan extant native yes
Bahamas extant native
Bangladesh extant native
Barbados extant vagrant
Belarus extant native yes
Belgium extant native yes
Bermuda (to UK) extant native
Bosnia and Herzegovina extant native
Bulgaria extant native yes yes
Canada extant native yes yes
China (mainland) extant native
Costa Rica extant native yes
Croatia extant native yes
Cuba extant native
Cyprus extant vagrant
Denmark extant native yes yes
Egypt extant uncertain
Estonia extant native yes yes
Faroe Islands (to Denmark) extant native yes
Finland extant native yes yes
France extant native yes yes
Georgia extant uncertain
Germany extant native yes yes
Gibraltar (to UK) extant vagrant
Greece extant native yes
Greenland (to Denmark) extant vagrant
Guam (to USA) extant uncertain
Hong Kong (China) extant vagrant
Hungary extant native yes
Iceland extant native yes
India extant native
Iran, Islamic Republic of extant native yes
Iraq extant native yes
Ireland extant native yes
Israel extant vagrant
Italy extant native yes
Jamaica extant vagrant
Japan extant native
Kazakhstan extant native
Latvia extant native yes yes
Liechtenstein extant native
Lithuania extant native yes
Luxembourg extant native
Malta extant vagrant
Mexico extant native
Mongolia extant vagrant
Montenegro extant native yes
Morocco extant vagrant
Myanmar extant native
Nepal extant native
Netherlands extant native yes
North Korea extant native
North Macedonia extant native yes
Northern Mariana Islands (to USA) extant native yes
Norway extant native yes
Pakistan extant native
Philippines extant native
Poland extant native yes yes
Portugal extant native yes
Puerto Rico (to USA) extant native
Romania extant native yes yes
Russia extant native yes yes
Russia (Asian) extant native yes
Russia (Central Asian) extant native yes yes
Russia (European) extant native yes yes
Serbia extant native yes
Slovakia extant native yes
Slovenia extant native yes
South Korea extant native
Spain extant native yes
St Pierre and Miquelon (to France) extant native yes yes
Svalbard and Jan Mayen Islands (to Norway) extant vagrant
Sweden extant native yes yes
Switzerland extant native yes
Taiwan, China extant native
Tunisia extant vagrant
Türkiye extant native yes
Turkmenistan extant native
Turks and Caicos Islands (to UK) extant native
Ukraine extant native yes yes
United Kingdom extant native yes
USA extant native yes
Vietnam extant native
Virgin Islands (to USA) extant vagrant

Important Bird and Biodiversity Areas (IBA)
Country/Territory IBA Name
Azerbaijan Aggyol
Azerbaijan Gizilagach
Canada Greater Rondeau Area
Canada Niagara River Corridor
Canada Old Crow Flats
Canada Presqu'ile Provincial Park
Canada Prince Edward County South Shore
Canada West End of Lake Ontario
Canada Wolfe Island
Denmark Bøjden Nor
Denmark Horsens Fjord, Svanegrunden & Endelave
Denmark Northern Kattegat
Denmark Odense Fjord
Estonia Irbe strait
Estonia Northern part of the Gulf of Riga
Estonia Nõva-Osmussaar
Estonia Pakri
Estonia Pärnu bay (NEW)
Estonia Saaremaa South
Estonia Väinameri
Estonia Vilsandi archipelago
Finland Käsivarsi fjelds
Finland Kevo
Finland Sammutinjänkä-Vaijoenjänkä
France Baie de Vilaine
France Boucle de Pose et de Muids
France Estuaire et embouchure de la Seine
France Lac Léman (partie française)
France Littoral Augeron
France Traicts et marais salants de la Presqu'île Guérandaise
Germany Brodtener Ufer
Germany Coast and lagoons of Western Pomerania
Germany Coastline of Probstei
Germany East- and south-east coast of Fehmarn
Germany Eastern bight of the Fehmarnsund
Germany Eastern part of Kiel Bight
Germany Flensburger Innen- and Aussenförde
Germany Greifswalder Bodden
Germany Grosser and Kleiner Binnensee
Germany Neustädter Bucht
Germany Sagasbank and eastern coast of Oldenburg
Germany Traveförde and Dassower See
Germany Wismar bay and Salzhaff
Iceland Miklavatn i Fljotum
Iceland Myvatn - Laxa
Ireland Carlingford Lough
Ireland Lough Gill
Ireland Lough Swilly including Blanket Nook and Inch Lake
Ireland Tralee Bay and Barrow Harbour
Ireland Wexford Harbour and Slobs
Japan Banzu and Futtsu tidal flat
Japan Inner Tokyo bay
Japan Isahaya bay
Japan Lake Furen, On-netou
Japan Lake Hamanako, Enshunada
Japan Lake Nakaumi
Japan Lake Shinjiko
Japan Notsuke, Odaitou
Japan Shiokawa tidal flat
Japan Yahagigawa estuary
Netherlands Lake IJsselmeer
Netherlands Wadden Sea
Norway Dovrefjell
Norway Hardangervidda
Norway Reisa
Norway Varanger Peninsula
Poland Lower Odra river valley
Poland Puck Bay
Poland Szczecin lagoon
Romania Black Sea
Russia (Asian) Abyy lowland
Russia (Asian) Bol'shaya River Estuary
Russia (Asian) Bolon' lake
Russia (Asian) Chaun delta
Russia (Asian) Chelomdzha valley and Kava-Chelomdzha interfluve
Russia (Asian) Gusikha river basin and lower Balakhnya river
Russia (Asian) Kanchalan river basin
Russia (Asian) Karaginskiy Island
Russia (Asian) Kharchinskoye lake
Russia (Asian) Kolyma delta
Russia (Asian) Kolyma-Alazeya lowland
Russia (Asian) Korfa Gulf (northern part)
Russia (Asian) Lebediny refuge (Markovo depression)
Russia (Asian) Lower Anadyr lowlands
Russia (Asian) Malkachan bay
Russia (Asian) Meinypylginski and Kapylgyn lakes
Russia (Asian) Moroshechnaya River
Russia (Asian) Nerpich'ye Lake and Kamchatka River delta
Russia (Asian) North-east Sakhalin lagoons
Russia (Asian) Parapol'skiy valley
Russia (Asian) Utkholok river
Russia (Asian) West Chaun plain
Russia (Central Asian) Basins of the Schuchya and Khadytayakha rivers
Russia (Central Asian) Dvuob'ye
Russia (Central Asian) Kondinskiye lakes
Russia (Central Asian) Lower Ob'
Russia (Central Asian) Lower Yuribey
Russia (Central Asian) Upper and Middle Yuribey
Russia (European) Berezoviye islands of Vyborg Bay
Russia (European) Bulgarski
Russia (European) Floodplains of the Unzha river near Kologriv
Russia (European) Kamsko-Ikski area
Russia (European) Lapland Biosphere Reserve
Russia (European) Lower Eruslan
Russia (European) Manturovo left bank of the Unzha river
Russia (European) Middle reaches of Bolshaya Rogovaya river
Russia (European) North-western subburbs of St.-Petersburg
Russia (European) Petrocrepost' Bay
Russia (European) Russki Zavorot Peninsula and eastern part of Malozemelskaya Tundra
Russia (European) Torna-Shoina watershed
Russia (European) Unskaya bay
Sweden Bay of Strandstugu
Sweden Coastal area of Eastern Gotland
Sweden Lake Ånn – Storlien
Sweden Vindel Mountains (including Lake Tärna)
Ukraine Molochnyj Liman
Ukraine Obytichna peninsula
Ukraine Utlyuk lyman
Ukraine Yagorlyts'ka and Tendrivs'ka Bays
United Kingdom Bridgend Flats, Islay
United Kingdom Carlingford Lough
United Kingdom Loch Ryan
United Kingdom Lochs of Harray and Stenness
United Kingdom Lough Neagh and Lough Beg
United Kingdom Moray Basin, Firths and Bays
United Kingdom Upper Solway Flats and Marshes

Habitats & altitude
Habitat (level 1) Habitat (level 2) Importance Occurrence
Grassland Tundra suitable breeding
Marine Neritic Estuaries major non-breeding
Marine Neritic Macroalgal/Kelp major non-breeding
Marine Neritic Pelagic marginal non-breeding
Marine Neritic Seagrass (Submerged) major non-breeding
Marine Neritic Subtidal Loose Rock/pebble/gravel major non-breeding
Marine Neritic Subtidal Rock and Rocky Reefs major non-breeding
Marine Neritic Subtidal Sandy major non-breeding
Marine Neritic Subtidal Sandy-Mud major non-breeding
Wetlands (inland) Bogs, Marshes, Swamps, Fens, Peatlands suitable breeding
Wetlands (inland) Permanent Freshwater Lakes (over 8ha) suitable non-breeding
Wetlands (inland) Permanent Freshwater Lakes (over 8ha) suitable breeding
Wetlands (inland) Permanent Rivers/Streams/Creeks (includes waterfalls) suitable breeding
Altitude   Occasional altitudinal limits  

Threats & impact
Threat (level 1) Threat (level 2) Impact and Stresses
Biological resource use Fishing & harvesting aquatic resources - Unintentional effects: (large scale) [harvest] Timing Scope Severity Impact
Ongoing Minority (<50%) Slow, Significant Declines Low Impact: 5
Stresses
Indirect ecosystem effects, Ecosystem degradation, Species mortality
Biological resource use Hunting & trapping terrestrial animals - Intentional use (species is the target) Timing Scope Severity Impact
Ongoing Minority (<50%) Negligible declines Low Impact: 4
Stresses
Species mortality
Climate change & severe weather Habitat shifting & alteration Timing Scope Severity Impact
Ongoing Majority (50-90%) Negligible declines Low Impact: 5
Stresses
Indirect ecosystem effects, Ecosystem degradation
Climate change & severe weather Other impacts Timing Scope Severity Impact
Ongoing Whole (>90%) Unknown Unknown
Stresses
Indirect ecosystem effects
Energy production & mining Oil & gas drilling Timing Scope Severity Impact
Ongoing Minority (<50%) Negligible declines Low Impact: 4
Stresses
Species disturbance, Ecosystem degradation, Ecosystem conversion
Energy production & mining Renewable energy Timing Scope Severity Impact
Ongoing Minority (<50%) Negligible declines Low Impact: 4
Stresses
Species disturbance
Pollution Industrial & military effluents - Oil spills Timing Scope Severity Impact
Ongoing Minority (<50%) Slow, Significant Declines Low Impact: 5
Stresses
Indirect ecosystem effects, Ecosystem degradation, Species mortality

Utilisation
Purpose Scale
Food - human subsistence, national
Pets/display animals, horticulture international
Sport hunting/specimen collecting subsistence, national

Recommended citation
BirdLife International (2024) Species factsheet: Greater Scaup Aythya marila. Downloaded from https://datazone.birdlife.org/species/factsheet/greater-scaup-aythya-marila on 22/11/2024.
Recommended citation for factsheets for more than one species: BirdLife International (2024) IUCN Red List for birds. Downloaded from https://datazone.birdlife.org/species/search on 22/11/2024.