Red-winged Blackbird (Agelaius phoeniceus) Fact Sheet: Summary

Kingdom: Animalia

Phylum: Chordata

Class: Aves — birds

Order: Passeriformes — passerines, or perching birds

Family: Icteridae — New World blackbirds

Genus: Agelaius (Vieillot, 1816) — red-winged blackbirds

Species: Agelaius phoeniceus (Linnaeus, 1766) — Red-winged Blackbird, a.k.a. “redwing”

Subspecies: About 20 to 22 subspecies recognized, based on physical characteristics; not all authorities accept all proposed subspecies. See current version of IOC World Bird List (Gill and Donsker 2019), Fraga (2014), and Yasukawa and Searcy (2019).

Sources: BirdLife International (2018), Gill and Donsker (2019)

Closet relative
Red-shouldered Blackbird, Agelaius assimilis (Yasukawa and Searcy 2019)

Body Weight
(Fraga 2014; Yasukawa and Searcy 2019)

Male: about 65 g (2.3 oz), on average

Female: about 43 g (1.5 oz), on average
Considerable variation in weight, depending on location and season.

Head-body Length
About 15 to 25 (6 to 10 in) (Yasukawa and Searcy 2019)

Male: 22.7 cm (8.94 in), on average (Fraga 2014)
Female: 18.5 cm (7.28 in), on average (Fraga 2014)

Populations and subspecies differ in body size and body proportions (Cornell Lab 2019).

General Appearance
Medium-sized blackbird. Beak pointed and cone shaped. Medium-length tail with square tip (Jaramillo and Burke 1999). Eyes dark.
Sexes differ in size and coloration (Jaramillo and Burke 1999; Yasukawa and Searcy 2019).

Coloration
(Jaramillo and Burke 1999; Fraga 2014, except as noted)

Adult male: Non-glossy black with red-and-yellow epaulets (“shoulder patches”). One subspecies of coastal southern California, A. p. mailliardorum, has very little yellow on epaulet (Cornell Lab 2019). Bill and legs black.

Adult female: Upperparts dark brown. Underparts buff with dark brown or blackish stripes. Head and cheeks have contrasting buff-and-brown stripes. Bill blackish-gray; paler at base.

Immature male: Blackish but streaked like adult female.

Immature female: Similar to adult female but chin and throat white.

Juvenile: Similar to immature female, but pale areas more yellowish.
Subspecies: Differ mainly in tone of female’s plumage.

Similar birds
Tricolored Blackbird, Agelaius tricolor (Jaramillo and Burke 1999)

Range
Canada to Mexico to Costa Rica. Entire United States, except Hawaii and western Alaska. Some Caribbean islands (e.g., Florida Keys, Bahamas, Turks and Caicos) (BirdLife International 2018; Cornell Lab 2019; Yasukawa and Searcy 2019).

Habitat
Found in a wide variety of habitats, primarily freshwater marshes and prairies (Yasukawa and Searcy 2019).

Breeding season: Marshes and ponds, wet meadows, roadside ditches, rice fields and other agricultural lands, suburban parks (Jaramillo and Burke 1999; Fraga 2014). Occasionally nest in woodlands near water (Cornell Lab 2019).

Nonbreeding season: agricultural fields, feedlots, pastures, grasslands, suburban areas, urban parks (Cornell Lab 2019; Yasukawa and Searcy 2019).

Elevation range: sea level to 3,000 m (10,000 ft) (Fraga 2014).

IUCN Status
Least Concern (2018 assessment) (BirdLife International 2018)

CITES Appendix
Not listed (UNEP 2019)

Other Designations
Protections under the U.S. Migratory Bird Treaty Act of 1918 modified to allow lethal and nonlethal population control to reduce damage to crops and other resources (Yasukawa and Searcy 2019; USFWS 2019).

Populations in the Wild
One of the most abundant birds in North America. Considered common to very common; locally abundant (Jaramillo and Burke 1999).

Approximately 210 million mature individuals (BirdLife International 2018).

Population trend: declining (BirdLife International 2018); greater than 35% decline from 1966 to 2014 (Rosenberg et al. 2016).

Threats to Survival
No significant threats—wide distribution, found in human-modified habitats (Fraga 2014).

Some subspecies in Mexico and Central America may be of local conservation concern (Fraga 2014). Climate change negatively affecting some blackbird populations (Forcey and Thogmartin 2017).

Activity Cycle
Active during the day, roost at night (Fraga 2014).

Movements
Roosting groups spread out during the day to forage (Fraga 2014). Travel up to 80 km (50 mi) to feed (Meanley 1965).

Species-level migration patterns complex: some populations migrate relatively short distances, some make long north-south migrations, and some migrate east–west or west–east. Populations in warmer climates (western U.S., Mexico, and farther south) mostly resident. Populations that breed in northern and northeastern North America overwinter in southern U.S. Distance traveled may span 600 to 1,000 km (400 to 600 mi) (Jaramillo and Burke 1999; Fraga 2014; Cornell Lab 2019).

Social Behavior
Roost in flocks: very large—up to several million birds—mixed-species groups during fall and winter; small groups in summer. Spread out to forage and establish territories during breeding. Single-sex flocks common during nonbreeding season (Jaramillo and Burke 1999; Fraga 2014; Cornell Lab 2019).

Communication
Various vocalizations, including clacking, buzzing, whistling, and growl-like calls. Male song typically a few sort notes, followed by a loud trill. Female makes a chatter-like song to males, sometimes in a duet; also “scream” and other calls during nest defense (Peek 1971; Brenowitz 1982; Knight and Temple 1988; Fraga 2014). Female also produces a buzzy series of calls in aggressive situations, especially in response to other females early in breeding season (Ken Yasukawa, personal communication, 2019).

Diet
Seeds of native and cultivated plants (e.g., corn, sunflower, oats). Insects, such as beetles, flies, and grasshoppers (McNicol et al. 1982; Mott et al. 1972; Bernhardt and Seamans 1990; Fraga 2014, Cornell Lab 2019).

Parents mostly feed chicks damselflies and dragonflies (Orians and Horn 1969).

Mainly forage on ground, exposing prey hiding under objects and among leaves of plants. Often forage in large flocks (hundreds of thousands of individuals) (Fraga 2014; Yasukawa and Searcy 2019).

Predators (non-comprehensive list)
(e.g., Shipley 1979; Knight and Temple 1988; Sawin et al. 2003)

• American Crow (Corvus brachyrhynchos)
• American mink (Mustela vison)
• Common Grackle (Quiscalus quiscula)
• Black-billed Magpie (Pica hudsonia)
• Raccoon (Procyon lotor)
• Marsh Wren (Cistothorus palustris)

Locomotion
Strong, agile fliers (Cornell Lab 2019). Walk and hop well on ground (Yasukawa and Searcy 2019).

Relationship with Humans
In the U.S. and Canada, considered an agricultural pest, particularly of corn, sunflower and rice. Control measures include shooting, poisoning, noise, sterilization, and cultivation of crop varieties resistant to damage (Werner et al. 2010; Cummings et al. 2011; Yasukawa and Searcy 2019). Blackbirds also feed on insect crop pests, which benefits farmers (e.g., McNicol et al. 1982; Bollinger and Caslick 1985). Considered a nuisance animal when roosting in large groups (Yasukawa and Searcy 2019).

Breeding
Season: March to July in most of North America; April to August in Costa Rica (Jaramillo and Burke 1999; Fraga 2014).

Male performs display (raises body feathers/epaulets, spreads tail) and sings to defend territories and attract mates (Nero 1956; Peek 1971; Peek 1972; Smith 1972; Yasukawa 1981; Jaramillo and Burke 1999). Typically mates with 2 to 4 (up to ~15) females, either sequentially or as harem (Fraga 2014). Female commonly mates with additional males (extra-pair copulations) (Westneat and Mays 2005).

Nest positioned low among marsh vegetation, shrubs, or trees (e.g., Stowers et al. 1968). Female lays 1 to 2 broods per breeding season. Eggs pale greenish-blue with dark spots and blotches (Jaramillo and Burke 1999). Eggs/young frequently taken by predators. In some regions, nests commonly parasitized by Brown-headed Cowbird (Clotfelter and Yasukawa 1999; Sawin et al. 2003).

Parental Care
Majority of care given by female. Cup-shaped nest constructed by female from plants, mud, peat, and dry grass. Both sexes defend nest. Female incubates eggs and feeds nestlings; male provides food in some circumstances. Young fed for about 2 weeks (Yasukawa et al. 1990; Patterson 1991; Fraga 2014).

Sexual Maturity
Male: Physically mature at 1 to 2 years old but not likely to hold territory until third year (Orians and Beletsky 1989; Wright and Wright 1944; Jaramillo and Burke 1999)

Female: 1 to 2 years old (Orians and Beletsky 1989; Yasukawa and Searcy 2019)

Clutch Size
North America: 2 to 5 eggs (Prather and Cruz 2006; Fraga 2014)

Costa Rica: 2 to 3 eggs (Fraga 2014)

Smaller clutch sizes in populations at tropical latitudes (Jaramillo and Burke 1999).

Weight at Hatching
About 3 g (0.01 oz), on average (Ohio population) (Holcomb and Twiest 1968)

Age at Fledging
About 10 to 12 days (Jaramillo and Burke 1999; Fraga 2014)

Typical Life Expectancy
Wild populations: mean life expectancy of about 2 years (Dyer 1977, using survival data from Frankhauser 1967)

Feature Facts

• One of the most abundant birds in North America (Cornell Lab 2019)
• Roost in enormous flocks during nonbreeding season (Fraga 2014)
• Wide variety of movement and migratory patterns (Jaramillo and Burke 1999)
• Learn what to eat by watching other Red-winged Blackbirds (Mason and Reidinger 1982)
• Extensive scholarly research on this bird’s breeding ecology (Linz et al. 2014)
• Well known for having nests parasitized by Brown-headed Cowbird (Clotfelter and Yasukawa 1999)
• Long history of conflict with humans: have caused damage to cereal crops since U.S. cultivation in the 1600s (Yasukawa and Searcy 2019)