How to Identify a Gadwall (Mareca strepera)

• Wing patch (speculum): Male and Female: square white patch on the trailing edge of the wing, obvious in flight and sometimes visible while swimming
• Body pattern: Male: mostly gray overall with a contrasting black stern (rear end)
• Bill: Male: narrow black-to-slate-gray bill. Female: orange bill with variable black markings
• Body pattern: Female: buffy tan overall with mottled plumage, white belly, and a slightly smaller white speculum than the male
• Behavior clue: Feeds by grazing or tipping up to reach submerged aquatic plants rather than foraging in upland crop fields

Gadwall female has a steeper forehead than female Mallard and shows a square white speculum patch rather than Mallard's blue-and-white speculum The Mallard page lists its own marks.

Lakes, ponds, marshes, around fresh or alkaline lakes in prairie regions; also coastal marshes and estuaries in migration and winter Widespread in North America; most common on inland waters west of the Mississippi River

Gadwall are dabbling ducks that feed by grazing or tipping up for submerged aquatic plants rather than in upland crop fields

Shoot from water level if you can, with the sun behind you, so head pattern and the wing patch show their true colors. Get one frame with the bird side-on and one as it stretches or flaps, which exposes the speculum and belly. Note who it is swimming with; ducks flock by species. The app names the likely species; confirm with the marks above, and check the female separately, since females of many ducks look alike.