I wonder how often I fail to recognize a gadwall as it swims amid a flock of mixed ducks. With their subtle brown plumage, gadwalls (Anas strepera), on first glance, can resemble the dull females of many duck species, particularly mallards.
Female gadwalls are a nondescript, mottled brownish on the head and body with a white belly. The female’s bill is black edged with orange. The breeding male with his tan face and darker brown crown is a little more colorful, but certainly does not display the bright colored patches and areas of other male ducks. His only bright color is a very faint reddish fringe on the long scapular feathers (where the wing joins the body). This red color is so diffuse and so pale that it almost looks pink or coral. The male gadwall’s scalloped black and white breast looks grey from a distance and his flanks are grey. A good field marking is the male’s black rump.
Leonard and I were wondering about the derivation of the unusual name, gadwall. Well, it appears as though everyone else does too. The references almost universally list the name gadwall as “origin unknown”. The spelling “gadwall” as a name for Anas strepera first appeared in print in 1676. There is a suggestion that the name could have come from “gad well” meaning “to go about well”. Or perhaps “gabble” meaning “rapid unintelligible talk” became “gadwell”. This makes as much sense as the species name, strepera, which means “noisy”. Except during breeding season the gadwall is a very quiet bird, and even during the breeding season is not particularly vocal.
Found over the greater part of the Northern Hemisphere, gadwalls are medium-distance migrants. Gadwalls in North America breed in the Dakotas and prairie states and winter in the southern states. There is a resident population in areas of the Northwest. We are lucky enough to be in the range (NE CAlifornia) where gadwalls can be found throughout the year.
A dabbling duck (tips to feed, does not dive to feed), gadwalls inhabit well-vegetated ponds and wetlands. They eat mostly submerged vegetation, however, will take aquatic invertebrates such as midges, water beetles and snails, particularly during the breeding season.
Gadwalls chose their breeding partners very early, usually by November. The monogamous pair stays together throughout the winter. Once the eggs are laid and incubation begins the male departs and joins a group of other males, leaving the female to incubate and raise the chicks on her own. The following fall new pairs form.
This gadwall pair was swimming on a pond at Crystal Lake Fish Hatchery (Shasta County CA).