Red-winged Blackbird

Red-winged Blackbird
Name	Red-winged Blackbird
Genus	Agelaius
Species	phoeniceus
Authority	(Linnaeus, 1766)

Red-winged Blackbird The red-winged blackbird is a passerine native to North America noted for its conspicuous shoulder patches and loud song. Males display red epaulets during territorial displays while females are streaked and cryptically colored for nesting. The species is widely studied across ornithology, wetland management, and conservation biology.

Description

Adult males exhibit glossy black plumage with distinctive red and yellow epaulets visible during display; adult females are brown-streaked with a buffy eyebrow and less conspicuous wing markings. Plumage variation has been documented in museum collections at the Smithsonian Institution, American Museum of Natural History, and Royal Ontario Museum and has been referenced in field guides produced by the Audubon Society, the National Geographic Society, and the Cornell Lab of Ornithology. Morphological studies often cite measurements from the Breeding Bird Survey and the North American Bird Banding Program, and compare wing, bill, and tail metrics with related taxa in the genus Agelaius and other members represented in the International Ornithological Congress checklist.

Distribution and Habitat

The species breeds across much of the United States and Canada and winters from the southern United States into Central America and parts of the Caribbean. It occupies freshwater and brackish marshes associated with vegetation studied by wetland ecologists at institutions such as Duke University, University of Florida, and University of California, Davis. Populations have been monitored in landscapes influenced by policies from the United States Fish and Wildlife Service, habitat restoration projects by The Nature Conservancy, and agricultural land managed under the United States Department of Agriculture conservation programs. Records from the Christmas Bird Count and the eBird database document regional abundance shifts linked to wetland drainage and land-use change.

Behavior and Ecology

Males establish and defend territories during the breeding season through song displays and flights accompanied by epaulet exposure; song structure and territoriality have been compared across populations sampled near the University of Michigan, the Smithsonian Migratory Bird Center, and research groups at Iowa State University. The species engages in polygynous mating systems studied in behavioral ecology literature from Harvard University and Princeton University and has been used as a model in sexual selection research cited in journals produced by the American Ornithological Society and the Royal Society. Red-winged blackbirds interact with predator guilds including Red-tailed Hawk, Great Blue Heron, and mammalian nest predators monitored in studies by the Rocky Mountain Bird Observatory. Vocalization studies reference acoustic datasets archived by the Macaulay Library and comparative analyses involving song dialects documented in fieldwork supported by the National Science Foundation.

Reproduction and Lifecycle

Nesting occurs in emergent vegetation or shrubs with nests built by females; clutch sizes, incubation periods, and fledging success are reported in longitudinal studies conducted at sites in the Great Lakes region, the Mississippi River basin, and coastal marshes along the Chesapeake Bay. Research on nesting success often cites methodological frameworks from the Institute for Bird Populations and demographic modeling approaches used by the US Geological Survey. Life-history parameters have informed population models employed by wildlife managers at the National Audubon Society and in policy assessments by the International Union for Conservation of Nature for broader passerine comparisons.

Diet and Foraging

The species is omnivorous, consuming seeds, insects, and agricultural grains, with seasonal shifts documented in studies conducted in agroecosystems evaluated by researchers at Iowa State University, University of Minnesota, and Cornell University. Foraging behavior in marsh edges and croplands has implications for interactions with managed species under programs like the North American Waterfowl Management Plan and research on crop depredation mediated through extension services from the United States Department of Agriculture. Trophic studies employing stable isotope analyses have been published in outlets affiliated with the Ecological Society of America and utilize lab facilities at institutions including Pennsylvania State University.

Conservation and Threats

While historically abundant, regional declines have been associated with wetland loss, pesticide exposure, and agricultural intensification documented in reports by the Environmental Protection Agency, the World Wildlife Fund, and national conservation assessments led by the United States Fish and Wildlife Service. Conservation actions emphasize wetland protection through programs run by organizations such as The Nature Conservancy, habitat easements administered under the Farm Bill, and monitoring by volunteer networks like the Audubon Christmas Bird Count and Partners in Flight. Ongoing research priorities include evaluating impacts of climate change scenarios from the Intergovernmental Panel on Climate Change on migratory timing and habitat availability, and assessing contaminant pathways studied by investigators at the United States Geological Survey and university toxicology centers.

Category:Agelaius