NT
Black Scoter Melanitta americana



Taxonomy

Taxonomic source(s)
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.
Livezey, B. C. 1995. Phylogeny and evolutionary ecology of modern seaducks (Anatidae: Mergini). Condor 97(1): 233-255.

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

Red List history
Year Category Criteria
2018 Near Threatened A2bce+3bce+4bce
2016 Near Threatened A2bce+3bce+4bce
2013 Near Threatened A2bce+3bce+4bce
2012 Near Threatened A2bce+3bce+4bce
Species attributes

Migratory status full migrant Forest dependency Does not normally occur in forest
Land mass type Average mass -
Extent of occurrence (EOO)

Estimate Data quality
Extent of Occurrence breeding/resident (km2) 17,700,000 medium
Extent of Occurrence non-breeding (km2) 46,900,000 medium
Number of locations -
Fragmentation -
Population and trend
Estimate Data quality Derivation Year of estimate
No. of mature individuals 350000-560000 poor estimated 2006
Population trend Decreasing suspected -
Decline (3 years/1 generation past) - - -
Decline (5 years/1 generation past) - - -
Decline (10 years/1 generation past) - - -
Decline (10 years/3 generation future) 20-29 - - -
Decline (10 years/3 generation past and future) 20-29 - - -
Number of subpopulations - - -
Largest subpopulations - - -
Generation length (yrs) 7.5 - - -

Population justification: The total population is estimated to number c.530,000-830,000 individuals (Delany and Scott 2006), probably including c.350,000-560,000 mature individuals, on the basis that they account for around 2/3 of the population.

Trend justification: This species is thought to be declining in western Alaska and to be stable on the Arctic coastal plain (per Sea Duck Joint Venture 2003). Numbers also appear to be declining in the Atlantic flyway, whereas no statistically significant population trend is apparent in the results of a fixed-wing aerial survey covering the Atlantic coast for the period 1991-1999 (Sea Duck Joint Venture 2003). Data from the U.S. Fish and Wildlife Service/Canadian Wildlife Service breeding waterfowl survey indicate that the combined population of all three scoter species along survey transects in the western boreal forest may have declined by as much as 75% since the 1950s (Sea Duck Joint Venture 2003). Estimates from a relatively new survey indicate that the breeding population in western Alaska is currently c.160,000 birds and appears to have increased slightly since the survey was initiated in 2004 (R. Stehn per T. Bowman in litt. 2012). Mid-winter inventory data do not indicate any trends on the Pacific coast and only show a weak decline on the Atlantic coast. However, these surveys are said to track scoter populations poorly and all three species are combined in one count (Sea Duck Joint Venture 2003). An analysis of Christmas Bird Count (CBC) data indicates an overall annual change of -1.26% between 1965-1966 and 2005-2006 across about half of the species’s range in North America (Butcher and Niven 2007). This equated to a decline of c.50% over 40 years, and thus suggests a c.32% decline over the last three generations (23 years), under the assumption of an exponential trend. However, CBC data are probably unreliable for tracking trends in this species because it winters predominantly offshore, where a large proportion of birds may not be visible to shore-based observers. Trends are apparently uncertain in far north-east Asia, where the species occurs east of Lena and numbers an estimated 300,000-500,000 birds or 12-24% of the estimated global population (see Delany and Scott 2006); thus more research is required. Limited data and anecdotal evidence from South Korea suggests that the species has declined substantially as a wintering species since the 1960s and 1970s (N. Moores in litt. 2012). On the basis of this mixed evidence, the population is suspected to be undergoing a moderately rapid decline (i.e. 20-29% over three generations).


Country/territory distribution
Country/Territory Occurrence status Presence Resident Breeding Non-breeding Passage
Canada N Extant Yes Yes Yes
China (mainland) N Extant Yes
Japan N Extant Yes
Mexico N Extant Yes
North Korea N Extant Yes
Russia N Extant Yes Yes Yes
Russia (Asian) N Extant Yes
South Korea N Extant Yes
St Pierre and Miquelon (to France) N Extant Yes Yes
USA N Extant Yes Yes Yes

Important Bird and Biodiversity Areas (IBA)
Country/Territory IBA Name
USA Marmot Bay
USA Prince William Sound
USA Kachemak Bay
Denmark Eastern German Bight
Russia (Asian) Karaginskiy Island
Russia (Asian) Bol'shaya River Estuary
Russia (Asian) Lesser Kuril Ridge and Kunashir Island
Russia (Asian) Nevskoye Lake
Russia (Asian) North-east Sakhalin lagoons

Habitats & altitude
Habitat (level 1) Habitat (level 2) Importance Occurrence
Marine Neritic Macroalgal/Kelp major non-breeding
Marine Neritic Pelagic suitable 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
Shrubland Boreal suitable breeding
Wetlands (inland) Tundra Wetlands (incl. pools and temporary waters from snowmelt) major 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 Majority (50-90%) Slow, Significant Declines Medium Impact: 6
Stresses
Indirect ecosystem effects, Ecosystem degradation
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
Future Majority (50-90%) Slow, Significant Declines Low Impact: 4
Stresses
Indirect ecosystem effects, Ecosystem degradation
Climate change & severe weather Other impacts Timing Scope Severity Impact
Ongoing Majority (50-90%) Slow, Significant Declines Medium Impact: 6
Stresses
Indirect ecosystem effects, Ecosystem degradation
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
Invasive and other problematic species, genes & diseases Viral/prion-induced diseases - Avian Influenza Virus (H5N1 subtype) Timing Scope Severity Impact
Future Minority (<50%) Rapid Declines Low Impact: 4
Stresses
Reduced reproductive success, Species mortality
Pollution Agricultural & forestry effluents - Nutrient loads Timing Scope Severity Impact
Ongoing Minority (<50%) Negligible declines Low Impact: 4
Stresses
Ecosystem degradation
Pollution Industrial & military effluents - Oil spills Timing Scope Severity Impact
Ongoing Minority (<50%) Slow, Significant Declines Low Impact: 5
Stresses
Ecosystem degradation, Reduced reproductive success, Species mortality
Transportation & service corridors Shipping lanes Timing Scope Severity Impact
Ongoing Minority (<50%) Negligible declines Low Impact: 4
Stresses
Species disturbance

Utilisation
Purpose Primary form used Life stage used Source Scale Level Timing
Pets/display animals, horticulture - - International Non-trivial Recent
Sport hunting/specimen collecting - - Non-trivial Recent

Recommended citation
BirdLife International (2020) Species factsheet: Melanitta americana. Downloaded from http://www.birdlife.org on 23/10/2020. Recommended citation for factsheets for more than one species: BirdLife International (2020) IUCN Red List for birds. Downloaded from http://www.birdlife.org on 23/10/2020.