Greater Scaup

Aythya marila

General Status Rank: 
Secure
ELCODE: 
ABNJB11060
Common Name: 
Greater Scaup
Scientific Name: 
Aythya marila
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Taxonomy
Group: 
Bird
Kingdom: 
Animalia
Phylum: 
Chordata
Class: 
Aves
Order: 
Anseriformes
Family: 
Anatidae
References: 
B004
General Biology

Longevity

average age unknown, oldest known male 22 years, oldest female 19 years
References: 
CS21

Economic/Human Considerations

important to sport hunters in southern Canada and US
References: 
B999
Habitat
deep freshwater
References: 
B004
H126
Distribution

Ecozones

Southern Arctic, Taiga Cordillera, Taiga Plains, Taiga Shield
References: 
B004

Distribution

0.65 (B004); ~85% of total NWT area. Range extent visually estimated from range map in "Distribution of birds in NWT & Nunavut: 2009 Review" (CWS).
Score: 
G
References: 
B004
Winter Distribution Description: 
almost exclusively marine, Pacific and Atlantic Coasts of Canada and US, Great Lakes

Number of Occurrences

dispersed breeder
References: 
H127

Historical Distribution

unknown, but possibly similar to present
References: 
H127

Area of Occupancy

unknown but prob stable
Score: 
-
References: 
W119
R265
Population

Population Size

1.7 million scaup spp. in NWT in 2014 (data from 2014 USFWS waterfowl breeding surveys, strata 13-18 (W119 accessed Feb 10, 2015)). GRSC make up ~15% of the continental scaup population (B999); ~255,000 in NWT.
Score: 
G
References: 
B999
W119

Density

dispersed breeder
Trends

Trends

Scaup spp. declined 16% since 1955 (W119 C. & N. Alberta–N.E. British Columbia–NWT transects (strata 13-18, 20, & 77)(R265)
Score: 
F
References: 
W119
R265
Threats

Threats

In the north, pollution, development, global climate change. In the south, potential over-hunting, habitat loss, pollution on wintering grounds and migration stops.
Score: 
C
References: 
B999
H308

Intrinsic Vulnerability

In north, pollution, development, global climate change
Score: 
-
References: 
B999
H308
General Status Rank
Rank: 
Secure
Status Rank Description: 
but declines are noted
S Rank: 
S5
Decision Process Description: 
Drafted by Jim Hines with review by S. Carriere, mostly based on printed material in 2000, Reviewed in 2005 by J. Hines and C. Swoboda based on printed literature only, no change in status; Reviewed in 2010;no change ; Reviewed by Ian Fife and Cindy Wood CWS in 2015, no change
Last Updated: 
February 17, 2015

References

Area of Occupancy

  • USFWS (2014) Accessed by CWS Region (Ian Fife and Cindy Wood) February 2015 https://migbirdapps.fws.gov/mbdc/databases/mas/maydb.asp - W119 Return
  • Zimpfer, Nathan L., Walter E. Rhodes, Emily D. Silverman, Guthrie S. Zimmerman, and Ken D. Richkus. (2014) U.S. Fish and Wildlife Service. Administrative Report July 2, 2014. http://www.fws.gov/migratorybirds/Newreportspublications/PopulationStatus/Trends/2014%20Trends%20in%20Breeding%20Duck%20Populations.pdf - R265 Return

Economic Status

  • Bellrose, RC (1980) Ducks, geese, and swans of North America. Wildlife Mangement Institute and Stackpole Books 3rd edition CWS office. Yellowknife - B999 Return

Ecozones

  • Godfrey WE (1986) The Birds of Canada. National Museums of Canada Revised Edition RWED Library Call #QL685.G6 - B004 Return

Habitat

  • Godfrey WE (1986) The Birds of Canada. National Museums of Canada Revised Edition RWED Library Call #QL685.G6 - B004 Return
  • Carrière, S. (2000) Pers. communication. Ecosystem Management Biologist; RWED - H126 Return

Historical Distribution

  • Hines, Jim (2000) Pers. communication. Wildlife biologist, CWS, Yellowknife - H127 Return

Intrinsic Vulnerability

  • Bellrose, RC (1980) Ducks, geese, and swans of North America. Wildlife Mangement Institute and Stackpole Books 3rd edition CWS office. Yellowknife - B999 Return
  • Cindy Wood and Ian Fife (2015) e-copy - H308 Return

Longevity

  • Kessel, B., D. A. Rocque, and J. S. Barclay (2002) Greater Scaup (Aythya marila) in The Birds of North America. The Academy of Natural Sciences and The American Ornithologists' Union No. 650 - CS21 Return

NWT Known Subspecies

Bellrose, RC (1980) Ducks, geese, and swans of North America. Wildlife Mangement Institute and Stackpole Books 3rd edition CWS office. Yellowknife - B999 Return

Number of Occurrences

  • Hines, Jim (2000) Pers. communication. Wildlife biologist, CWS, Yellowknife - H127 Return

Population Size

Bellrose, RC (1980) Ducks, geese, and swans of North America. Wildlife Mangement Institute and Stackpole Books 3rd edition CWS office. Yellowknife - B999 Return
,
USFWS (2014) Accessed by CWS Region (Ian Fife and Cindy Wood) February 2015 https://migbirdapps.fws.gov/mbdc/databases/mas/maydb.asp - W119 Return

Range Extent

  • Godfrey WE (1986) The Birds of Canada. National Museums of Canada Revised Edition RWED Library Call #QL685.G6 - B004 Return

Short Term Trends

  • USFWS (2014) Accessed by CWS Region (Ian Fife and Cindy Wood) February 2015 https://migbirdapps.fws.gov/mbdc/databases/mas/maydb.asp - W119 Return
  • Zimpfer, Nathan L., Walter E. Rhodes, Emily D. Silverman, Guthrie S. Zimmerman, and Ken D. Richkus. (2014) U.S. Fish and Wildlife Service. Administrative Report July 2, 2014. http://www.fws.gov/migratorybirds/Newreportspublications/PopulationStatus/Trends/2014%20Trends%20in%20Breeding%20Duck%20Populations.pdf - R265 Return

Taxonomy

  • Godfrey WE (1986) The Birds of Canada. National Museums of Canada Revised Edition RWED Library Call #QL685.G6 - B004 Return

Threats

  • Bellrose, RC (1980) Ducks, geese, and swans of North America. Wildlife Mangement Institute and Stackpole Books 3rd edition CWS office. Yellowknife - B999 Return
  • Cindy Wood and Ian Fife (2015) e-copy - H308 Return