In the breeding season Red-winged Blackbird is abundant to locally uncommon in most parts of Texas. Incubation lasts about 11 days (range 10-12) and 2 broods per season are frequent. The female usually lays 4 bluish-green eggs (range 2-6 see Harrison for photo of markings). Nests, built in 3-6 days by the female, are bulky, substantial, woven baskets, built of strips of grass, rushes, sedges, reeds, plant stems, or leaves, and lined with finer materials. They may also be found in trees as high as 12 m (40 ft) above ground. Nests are often placed in cattails or other marsh vegetation or in Baccharis bushes. Red-winged Blackbird breeds from sea level to 1200 m (4000 ft) in loose colonies in freshwater marshes, wet meadows, stream-side bushes, swamps, pastures, and floodplains. The atlasers reported nest building occurring from March 17 to June 25 (most dates in May), nests with eggs May 16 to July 6, female on or near nest May 1 to July 17, nests with young April 8 to June 25, feeding of nestlings or fledglings April 8 to July 28, and recent fledglings May 8 to July 26,īREEDING HABITAT. Oberholser (1974) reported egg dates extending from April 17 to July 19. TBBA workers found Red-winged Blackbirds engaged in breeding activities from March 17 to July 26. In winter migrants from the north increase the population of this species in Texas, but the size and composition of mixed species flocks in which Red-winged Blackbirds are found in winter is difficult to measure even at night roosts. West of this meridian and south of the 32nd parallel, breeding sites in the Trans-Pecos and Edwards Plateau regions are more widely scattered. During the 1987-1992 field work for the TBBA project, atlasers found Red-winged Blackbirds breeding most commonly in Texas east of the 100th meridian and throughout the Panhandle. Yasukawa and Searcy (1995) and Pyle (1997) provide description and ranges of currently assigned subspecies.ĭISTRIBUTION. Although the species varies in size and slightly in plumage across its range in the United States, Canada and Mexico, the number of subspecies appears excessive, and further study is needed, as the evidence provided for separating populations seems inadequate. Many of the roughly two dozen recognized subspecies of Red-winged Blackbird either reside or winter in Texas. Flocks moving between feeding area and roost sites are often of impressive size (Oberholser 1974). Feeding flocks in fields may move in a pattern with birds at the rear flying over the flock to alight in front. Red-winged Blackbird is especially conspicuous in winter when the species gathers in sometimes enormous flocks with other blackbirds, grackles and cowbirds to forage on weed seeds, grain spilled at harvest or at cattle feedlots. They spend their pre-breeding years as “floaters” around colonies, waiting for a territory to become available (Yasukawa and Searcy 1995). While almost all females breed in the second year of life, most males do not become territory holders until their third or later year, when they have acquired the glossy, black plumage with red “epaulets” on their wings. ![]() Males are often polygamous and vigorously defend territories, containing up to 15 nests, against other Red-winged Blackbirds. For further plumage details and confusing subspecies taxonomy see Yasukawa and Searcy (1995) and Pyle (1997). No other species in Texas should be confused with Red-winged Blackbirds. Third-year and older males are glossy black with red “epaulets” bordered in yellow, while second-year males are highly variable, ranging from a female-like plumage to black with brown flanks and variably colored epaulets. Since almost all females two-years or older breed, plumage details do not appear to matter to males, many of which are polygamous. Second year females are duller in these two areas. ![]() Third-year and older females are variable in throat (pink to buffy) and epaulet (dull orange to bright orange-red) color. Red-winged Blackbird is a common and conspicuous breeding resident of much of Texas, even more widespread in winter when migrants arrive from further north.Īles and females of this species differ strikingly in plumage, not unusual for blackbirds and orioles.įemales of all ages are mottled brown above and heavily streaked below with a white eyebrow stripe.
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