Redhead, Aythya americana
Redhead, Aythya americana, Male. Photograph taken in the San José del Cabo Rió Lagoon, Baja California Sur, March 2012. Photograph courtesy of Carol Snow, Del Mar, California.
Redhead, Aythya americana, Males. Photographs taken in rural Baynorillo, Sonora, March 2022. Photograph and identification courtesy of David F Smith, Alamos, Sonora.
The Redhead, Aythya americana, is a dabbling duck and a member of the Anatidae Family of Duck, Geese and Waterfowl, which has one hundred seventy-four members placed in fifty-three genera, and one of twelve global species of the Aythya Genus. It belongs to a group of North American pochards of the genus Aythya known collectively as “bay ducks,” which include Canvasbacks, Lesser Scaups, Greater Scaups, and Ring-necked Ducks. The Redhead is known in Mexico as pato cabecirrojo.
The Redhead is restricted to North America and summers and breeds widely throughout the western United States and Canada. It is estimated that more than 1,000,000 Redheads make annual fall and spring migrations to wintering grounds primarily in the coastal areas along the Gulf of Mexico, with hundreds of thousands of birds traditionally found in the Laguna Madre of Texas and the Laguna Madre of Tamaulipas, Mexico. They are found in limited numbers throughout all of Mexico on inland lakes and reservoirs with the exception that they are absent from Guerrero, Oaxaca, Chiapas, and the Yucatán Peninsula. They are
The Redhead is a medium-sized diving duck. The adults are sexually dimorphic with the males being larger than the females. Adult male when breeding have a rufous head and neck, black breast, gray body, black hindquarters, yellowish eye, and blue-gray bill with black tip and white subterminal band. The females are a uniform plain brownish with whitish belly, grayish secondaries, and a pale whitish chin. The adult males have a pale cobalt blue bill with a black tip that is bordered by a faint white ring; the females bills are darker blue to black or dark salty gray with a pale subterminal band. The iris of the adult male is yellowish orange and brown or yellowish brown in adult females. Their legs and feet are gray.
The Redhead breeds primarily in the western United States and southern Canada and winters along the Atlantic Coast in coastal lagoons and bays that have shallow water sand flats that are sparsely vegetated with manateegrass, shoalgrass, stargress, turtlegrass or widgeongrass. Year-round breeding populations have been documented in Jalisco and in the Federal District in south-central Mexico. They feed primarily on shoalgrass rhizomes and saltwater mollusks in flocks of hundreds or thousands by diving, tipping, dipping or gleaning food off the water surface. Along the Pacific coast their main food is widgeongrass. In large inland lakes they consume submerged aquatic plants. They feed in mixed flocks with American Coots, American Wigeons, Canvasbacks, Gadwills, Lesser Scaup, Northern Pintails and Tundra Swans.
The Redheads are generally non-aggressive and tolerant of other species of waterbirds and known for their highly gregarious personalities during the majority of the year. They undergo a seasonal prebasic molt in late summer where they lose their flight feathers and are found as restless swimming flocks of several hundred individuals for three or four weeks. They sleep on water and rely on their water habit to avoid predation. They form monogamous pairs in late winter constructing nests in dense emergent vegetation in deep marshes. They remain together until their eggs hatch at which time the males depart and leave the females to raise the young. The Redhead has drawn the attention of the scientific community due to its brood parasitism whereby a breeding female may lay her own eggs, parasitizes another’s nest before laying her clutch, or parasitizes other duck nests without producing a clutch of her own.
The male Redhead is most likely confused with the Canvasback, Aythya valisineria (darker more brownish red head; peaked crown and gently sloping forehead; longer bill). The females are darker colored than the female Canvasbacks. The females are similar to Greater Scaup, Aythya marila, Lesser Scaup, Aythya affinis, and Ring-necked Duck, Aythya collaris, but all are smaller in stature and darker in color.
The Redhead is restricted to North America and summers and breeds widely throughout the western United States and Canada. It is estimated that more than 1,000,000 Redheads make annual fall and spring migrations to wintering grounds primarily in the coastal areas along the Gulf of Mexico, with hundreds of thousands of birds traditionally found in the Laguna Madre of Texas and the Laguna Madre of Tamaulipas, Mexico. They are found in limited numbers throughout all of Mexico on inland lakes and reservoirs with the exception that they are absent from Guerrero, Oaxaca, Chiapas, and the Yucatán Peninsula. They are normally mixed in with American Wigeons, Lesser Scaups, and Northern Pintails.
From a conservation perspective the Redhead is currently considered to be of Least Concern with stable, widely distributed populations. Although they are wide-ranging and have a high degree of flexibility in habitat and food used their numbers are less than other prairie nesting birds of North America. They are pursued by hunters and taken at a level of 250,000 birds per year by recreational hunters in the United States and are also prone to human disturbance. Their long-term survival is dependent upon the retention of their wetland breeding and wintering territories in native conditions. Their wintering grounds in Mexico are subject to hypersalinity events that eliminates the grass beds on which they depend for survival. They date to the Pleistocene period, 2.6 million years ago, with fossils being found in Jalisco.