The Red-Winged Blackbird (Agelaius phoeniceus) is smaller than a robin in size. Females and young are heavily streaked with dusky brown. Although primarily a marsh bird, the red-winged blackbird will nest near virtually any body of water and occuasionally breeds in upland pastures. After the breeding season, the birds gather with other blackbirds in flocks, sometimes numbering in the hundreds of thousands. Sweetwater Wetlands Tucson, AZ.