Photo Credit: Gadwall – Brima Battle/UFWS

Gadwall

Anas Strepera

Compiled by Niyati Acharya

Gadwall is a wigeon-sized duck that nests in freshwater marshes and on lakes and impoundments.  Gadwall’s range has expanded to include the Atlantic coast and the Northwestern U.S.  The species fly swiftly in tight flocks.    Courting males perform complex displays, including aerial chases.  Listen for a Mallard-like quack (female), a sweet, squeaky piping; a flat, nasal map(male).  The adult male has pale, rusty-edged scalpulars, gray tertials, white inner secondaries (prominent in flight), and black tail coverts.  The adult female has plumage more strikingly patterned than female Mallards, a dark bill with narrow, orange siders, and a contrasting, white belly patch.  They have a life-span of 5 – 10 years.

Gadwall numbers have increased since the 1980s, partly because of conservation of wetlands and adjacent uplands in their breeding habitat through the Conservation Reserve Program and the North American Waterfowl Management Plan. Their habit of nesting on islands within marshes gives them some protection from predators.

Gadwalls eat submerged aquatic vegetation such as algae, grasses, rushes, sedges, pondweed, widgeon grass, and water milfoil, including leaves, stems, roots, and seeds.  They also eat snails, midges, water beetles, and other invertebrates.  During the breeding season, animal matter can account for nearly 50 percent of an adult Gadwall’s diet, but this proportion drops to only about 5 percent animal matter during winter.

The Gadwall is sometimes referred to as the “gray duck” because of its overall gray-brown color.   Their population increased by about 1.7% per year between 1966 and 2019, according to the North American Breeding Bird Survey.  Partners in Flight estimates the global breeding population at 4.4 million individuals, indicating a species of low conservation concern.   

Gadwalls are the third most hunted duck species (after Mallard and Green-winged Teal).  Duck harvests are carefully managed, and Gadwall numbers are still strong, in part because of the conservation of both wetlands and adjacent upland nesting habitat through the Conservation Reserve Program and the North American Waterfowl Management Plan, as well as the efforts of private conservation groups such as Ducks Unlimited.

Gadwalls will use marshes, small ponds, and lakes for breeding habitats.  They like water in open areas that are not bordered by dense forests or other vegetation (except for grasses and shrubs).  In Nevada, Gadwalls are found throughout the state during the breeding season and non-breeding season.  In the Northwest part of the state, they can be found year-round.

Sources include: NDOV.org, Allaboutbirds.org, 

Photo credit:  Brima Battle/UFWS, Koerner, Tom/USFWS, Kramer, Gary/USFWS, Chuck Loesch/USFWS