Status: Common, locally abundant, regular spring and fall migrant statewide. Common regular breeder north-central Nebraska and Sandhills, uncommon south-central, rare casual elsewhere. Rare, locally uncommon, regular winter visitor Platte, North Platte, and South Platte River Valley counties southward, rare casual elsewhere.
Documentation: Specimen: KSC Olson #20, 20 Mar 1906 Kearney, Buffalo Co.
Taxonomy: No subspecies are recognized. This species was recently moved from genus Anas to genus Mareca, based on genetic studies (Chesser et al 2017).
Occasionally Gadwall hybridizes with Northern Shoveler and Mallard; for Nebraska records, see Hybrids – Birds of Nebraska – Online (outdoornebraska.gov).
Spring: Feb 21, 21, 21 <<<>>> summer
Early dates above are away from the winter range; earlier such dates are 13 Feb 2018 Cedar Co, 17 Feb 2012 two in Garfield Co, and 17 Feb 2017 three in Cedar Co. These dates suggest northward movement beginning in mid- to late Feb, although first arrivals in numbers are typically seen in early Mar as open water becomes available. As many as 31 were in Cedar Co 5 Feb 2019 where only one had been present earlier. Numbers peak in early Apr, and migration is usually over by early May.
- High counts: 2600 at Crescent L NWR, Garden Co 15 Apr 1980, 1800 at Harvard WPA, Clay Co 9 Apr 2000, and 1750 at Crescent Lake NWR 23 Apr 1996.
Summer: It has been shown that Gadwall expanded into North America from Eurasia relatively recently, perhaps ca. 81,000 years ago, although the large confidence interval associated with this estimate, 8500-450,000 years (Peters et al 2008), renders establishing an accurate timeline difficult at best. This species has its North American population center in the Prairie Pothole Region, and expansion to the east, west, and north has occurred only in the latter 20th Century (Leschack et al 2020); it was first reported breeding in the eastern US in 1939, in the Great Lakes in the 1960s, and the west coast in the 1970s. It is thought that man-made structures such as impoundments, dredge spoil areas, and water treatment plants have contributed to its increase in the US (Leschack et al 2020).
Highest breeding densities occur in the Sandhills and to a much lesser extent the Rainwater Basin. In the Sandhills it was the fourth most common dabbling duck after Blue-winged Teal, Mallard, and Northern Shoveler; Vrtiska and Powell (2011) estimated for 2003-2005 an average annual total of 17,516 Gadwalls. Harding (1986) found 32 nests in Clay Co 1981-85, the third most common nester after Blue-winged Teal and Mallard, although a hen and brood in York Co 16 Aug 2003 was the first evidence of Rainwater Basin breeding in at least 15 years (Jorgensen 2012). This 15-year gap corresponds to North American population fluctuations due to changing water conditions from dry conditions in the early 1980s to much higher levels in the 1990s (Leschack et al 2020).
Nesting reports away from the Sandhills and Rainwater Basin are few: Cuming Co (Wensien 1962), Dawes and Sioux Cos (Rosche 1982; Ducey 1988), Scotts Bluff Co, Lancaster Co (Cink 1971, 1975), Saunders Co (Ducey 1988), and Webster Co (Wensien 1962).
Reports mid-Jun through mid-Jul away from the mapped summer range may indicate breeding.
- Breeding phenology:
Incubation: 26 May-14 Jul
Dependent fledglings: 13 May-20 Jul.
Fall: summer <<<>>> Dec 13, 13, 14
Late dates above are away from the winter range. Jul, Aug, and early Sep reports from areas where breeding did not occur are likely of molt migrants, which disperse in any direction, often for long distances (Palmer 1976). True migration becomes evident by late Sep; 200 were in Lincoln Co 14 Sep 2011. Migrating numbers peak in late Oct, although good numbers may be present well into Dec provided open water is available, usually within the winter range. As many as 575 were at Lake McConaughy 30-31 Dec 2011; in the east, 50 were still in Cedar Co as late as 26 Dec 1994. There are few reports after mid-Dec away from the winter range (see Winter).
- High counts: 5800 at Lake McConaughy, Keith Co 31 Oct 2006, 2200 at Crescent Lake NWR 9 Oct 1996, and 2030 in Lancaster Co 3 Nov 1998.
Winter: This species usually over-winters in the Platte, North Platte, and South Platte River Valley counties southward, including the lower Missouri River counties, given open water conditions. The few records away from these locations in mid-winter are mostly from Cedar Co: 4-20 Jan 2018, 4 Jan 2019, 5 Jan 2012, 2-10 Feb 2020. The only records elsewhere are 9 Jan 2020 Madison Co and 25 Jan 2020 Loup Co.
Previously, only small numbers wintered, but more recently these numbers have increased. Of about 82 reports for the period 12 Jan-5 Feb, 48 were in the winters 2012-2021. Best counts were 24 at Scottsbluff SL 14 Jan 2016 and 16 there 23 Jan 2015 increasing to 27 on 13 Feb as migrants began arriving.
- High counts: 373 at Lake Ogallala, Keith Co 29 Jan 2000, 62 at Clear Creek WMA, Keith Co 16 Jan 2000, and 32 at Two Rivers SP, Douglas Co 16 Jan 1995.9 J
KSC: Kearney State College (now University of Nebraska-Kearney)
NWR: National Wildlife Refuge
SL: Sewage Lagoons
SP: State Park
WPA: Waterfowl Production Area (Federal)
Photograph (top) of a Gadwall pair at Fontenelle Forest, Sarpy Co, 6 Mar 2009 by Phil Swanson.
Chesser, R.T., K.J. Burns, C. Cicero, J.L. Dunn, A.W. Kratter, I.J. Lovette, P.C. Rasmussen, J. V. Remsen, Jr., J.D. Rising, D.F. Stotz, and K. Winker. 2017. Fifty-eighth supplement to the American Ornithological Society’s Check-list of North American Birds. Auk 134: 751-773.
Cink, C.L. 1971. Some interesting summer bird records for Lancaster County in 1970. NBR 39:58-59.
Cink, C.L. 1975. Some waterfowl breeding records for Lancaster County. NBR 43: 40-41.
Ducey, J.E. 1988. Nebraska birds, breeding status and distribution. Simmons-Boardman Books, Omaha, Nebraska, USA.
Harding, R.G. 1986. Waterfowl nesting preferences and productivity in the Rainwater Basin, Nebraska. Master’s thesis, Kearney State College, Kearney, Nebraska.
Jorgensen, J.G. 2012. Birds of the Rainwater Basin, Nebraska. Nebraska Game and Parks Commission, Lincoln, Nebraska, USA.
Leschack, C.R., S.K. McKnight, and G.R. Hepp. 2020. Gadwall (Mareca strepera), version 1.0. In Birds of the World (S. M. Billerman, Editor). Cornell Lab of Ornithology, Ithaca, NY, USA. https://doi.org/10.2173/bow.gadwal.01.
Palmer, R.S., ed. 1976. Handbook of North American birds. Vol. 2. Waterfowl (Parts 1 and 2). Yale University Press, New Haven, Connecticut, USA.
Peters, J.L., Y.N. Zhuravlev, I. Fefelov, E.M. Humphries, and K.E. Omland. 2008. Multilocus phylogeography of a Holarctic duck: colonization of North America from Eurasia by Gadwall (Anas strepera). Evolution 62: 1469-1483. https://doi.org/10.1111/j.1558-5646.2008.00372.x.
Rosche, R.C. 1982. Birds of northwestern Nebraska and southwestern South Dakota, an annotated checklist. Cottonwood Press, Crawford, Nebraska, USA.
Vrtiska, M.P., and L. Powell. 2011. Estimates of Duck Breeding Populations in the Nebraska Sandhills Using Double Observer Methodology. Waterbirds 34: 96-101.
Wensien, R. 1962. Nesting report, 1961. NBR 30: 24-25.
Silcock, W.R., and J.G. Jorgensen. 2021. Gadwall (Mareca strepera). In Birds of Nebraska — Online. www.BirdsofNebraska.org
Birds of Nebraska – Online
Updated 5 Jul 2021