Nomonyx – Masked duck

A tiny, sneaky cousin of the ruddy duck, dressed up for a tropical swamp party. It’s one of the smallest stiff-tailed ducks in the Americas, with a compact body, chunky rump, and that trademark stiff tail it often cocks up at an angle. Breeding males are surprisingly flashy up close: rich rusty-chestnut body, dark mottled wings, and a solid black “mask” covering the face that gives the species its name. Females, immatures, and non-breeding males look much more low-key, with finely barred brown-gray plumage and two dark stripes running across a buffy face, making them look a bit like miniature female teal.

Its range stretches from southern Texas and Mexico through Central America into much of northern and eastern South America, plus the Caribbean islands. It favors warm, weedy wetlands—swamps, marshes, ponds, mangrove edges—with thick floating or emergent vegetation where it can vanish almost completely. In the United States, it’s a shy tropical visitor: often present in very small numbers and easy to miss, its appearance is linked to longer-term drought-and-flood cycles that open or close suitable habitat.

The masked duck’s lifestyle is all about staying hidden. Rather than cruising around in the open like many ducks, it spends long stretches tucked into dense marsh growth, sometimes clambering through reeds almost like a rail. When it does feed, it prefers to dive among the stems and lily pads, surfacing only briefly before disappearing again. Its diet is a mix of seeds, roots, stems, and leaves of aquatic plants, plus aquatic insects and small crustaceans—basically whatever it can find by rummaging around underwater. In many places it’s seen singly or in pairs, but in good wetlands it can gather in small groups or loose flocks that are still easy to overlook because almost everyone is half-hidden among the reeds.