Gadwalls are medium-sized ducks characterized by a general lack of bright coloration. Males are gray-brown, with a white belly, and a black rump. In flight, a white speculum and chestnut and black portions on the wing coverts are displayed. The bill is slate-gray and the legs and feet are yellow. The male utters a short “nheck” and a low whistle. Female gadwalls are similar to males, but have a mottled brown appearance, a yellowish bill with dark spots, and a smaller white speculum. She utters a repeated “gag-ag-ag-ag-ag” higher in pitch than the mallard.
Female gadwall nest in fields and meadows, and on islands and dikes in wetlands. They are found in reservoirs, farm ponds, and coastal fresh and brackish marshes.
A species breeding in the temperate regions of North America and Eurasia. The breeding populations of the western parts of the European Union are more or less sedentary, but they are increased in winter by migratory birds from the Baltic region. This population is totalling 30000 individuals, and seems to have increased during the last decades (Scott & Rose). The birds breeding in Greece or visiting Greece in winter belong to a more oriental population, estimated at 75000-150000 individuals but currently declining
Aquatic vegetation makes up the majority of the gadwall’s diet. As a result, they are often found feeding far from the shoreline, in deeper water than most other dabbling ducks. Gadwall up-end to feed on leafy portions of pondweeds, naiad, widgeon grass, water milfoil, and algae and the seeds of pondweeds, smartweeds, bulrush, and spike rush. They also feed on aquatic invertebrates, such as crustaceans and midges.
This species has a large range, with an estimated global Extent of Occurrence of 10,000,000 km². It has a large global population estimated to be 3,800,000-4,400,000 individuals (Wetlands International 2002). Global population trends have not been quantified, but the species is not believed to approach the thresholds for the population decline criterion of the IUCN Red List (i.e. declining more than 30% in ten years or three generations). For these reasons, the species is evaluated as Least Concern. [conservation status from birdlife.org]
Gadwall breed near seasonal and semi-permanent wetlands, mainly in the shortgrass, tallgrass, and mixed prairie regions of the US and Canada. Substantial numbers also breed in wetland habitats of the Great Basin. Gadwall tend to begin breeding later than most ducks. Female gadwall nest in fields and meadows, and on islands and dikes in wetlands and lay an average of 7 to 12 eggs.
Partially migratory; northernmost breeding birds descend to lower latitudes in winter, but breeders of more temperate regions mostly sedentary.
- spanwidth min.: 78 cm
- spanwidth max.: 90 cm
- size min.: 46 cm
- size max.: 56 cm
- incubation min.: 24 days
- incubation max.: 26 days
- fledging min.: 45 days
- fledging max.: 50 days
- broods 1
- eggs min.: 8
- eggs max.: 12
- Conservation Status