Aythya marila nearctica
Status: Uncommon regular spring and fall migrant statewide. Locally common winter visitor statewide. Rare casual summer visitor statewide.
Documentation: Specimen: UNSM ZM14529, 9 Apr 1904 Waco, York Co.
Taxonomy: Eurasian Greater Scaup have been separated from Western Hemisphere birds as A. m. marila (Gill and Donsker 2017). Nebraska birds are presumed nearctica, the Western Hemisphere subspecies.
Spring: Feb 3, 3, 5 <<<>>> May 18, 19, 19
This species is an early migrant, arriving as water opens. There is an earlier date 27 Jan 2016 of eight at Lake Ogallala, Keith Co. Peak numbers occur in late Mar. There areis a surprising number of reports into late May; because Greater Scaup do not breed until two years old (Baldassarre 2014), we consider these non-breeding immatures. The records are 1-2 on 21-24 May Valentine NWR, Garden Co, 26 May 2013 Douglas Co, 27 May 2016 Lake Ogallala, Keith Co, 28 May 1982 Sheridan Co, 31 May 2016 York Co, and a male photographed at Heron WPA, York Co 31 May 2016. (see Summer).
- High counts: 60 at Keystone Lake, Keith Co 25 Mar 2000, 50 there 23 Mar 2011, and 43 there 17 Mar 2001.
Summer: There are only four reports Jun-Sep, all of photographed females: Lancaster Co 6-26 Jun 2018, Scotts Bluff Co 16 Jun 2019, Fillmore Co 3 Jul 2005, and at Harvard WPA, Clay Co 20 Jul 2013.
Fall: Oct 18, 20, 20<<<>>> Jan 5, 5, 5
There are earlier reports 3 Oct 1987 Washington Co, 11 Oct 2014 Lancaster Co, 11 Oct 2018 Lancaster Co (3), and 12 Oct 2000 Lake Ogallala, and a later report 13 Jan 2013 Carter Lake, Omaha. Most reports are in late Nov and early Dec. Late dates above are from areas where wintering did not occur.
- High counts: 86 at Lake Ogallala 27 Dec 2006, 77 there 14 and 19 Nov 2000, 65 there 2 Jan 2011, and 54 there 16 Dec 2001.
Winter: Since about 1990 this species has become a regular winter visitor at certain locations. At Lake Ogallala, it was described as a “locally fairly common to common winter visitant” (Rosche 1994); as many as 74 have been recorded there in mid-winter. Less regular locations include Scottsbluff SL, Scotts Bluff Co, where there were 2-3 on 15-19 Jan 1998, two on 12 Jan 2002, three from 30 Jan to 13 Feb 2006, and Alma SL, Harlan Co, where there were two on 18 Jan 2013, one on 27 Jan 2013, a female 29 Jan-1 Feb 2003, and four wintering 1999-2000.
The only midwinter reports elsewhere are of one in Madison Co 18 Jan 2014, four below Gavin’s Point Dam, Cedar Co 20 Jan 2018 and one there 22 Jan 2009, and one in Douglas Co 1 Feb 2019.
- High counts: 74 at Lake Ogallala winter 1999-2000, 40 there 31 Dec 2016, and 32 in Keith Co 13 Jan 1991 (Rosche 1994).
NWR: National Wildlife Refuge
SL: Sewage Lagoons
UNSM: University of Nebraska State Museum
WPA: Waterfowl Production Area (Federal)
Photograph (top) of a Greater Scaup in the Central Nebraska Public Power and Irrigation District canal downstream of Lake Ogallala, Keith Co, on 24 Mar 2018 by Boni Edwards.
Baldassarre, G. 2014. Ducks, geese, and swans of North America. Johns Hopkins University Press, Baltimore, Maryland, USA.
Gill, F., and D. Donsker (Eds). 2017. IOC World Bird List (v 7.3), accessed 30 January 2018.
Rosche, R.C. 1994. Birds of the Lake McConaughy area and the North Platte River valley, Nebraska. Published by the author, Chadron, Nebraska, USA.
Silcock, W.R., and J.G. Jorgensen. 2020. Greater Scaup (Aythya marila), Version 1.0. In Birds of Nebraska — Online. www.BirdsofNebraska.org