Red-winged Blackbird

Agelaius phoeniceus Linnaeus

STANFORD LOCATIONS:

Common breeder in mustard and other herbaceous vegetation on the hills near the Dish and near Lagunita, fairly rare as a breeder elsewhere on campus. A few pairs may nest in the wetland area south of Campus Drive between Lomita Drive and Palm Drive. During the nonbreeding season, small numbers (and occasionally flocks) may forage throughout campus.

  

Nest
Location
Nest
Type
Eggs &
Mating System
Dev. &
Parental Care
Primary &
2ndary Diet
Foraging
Strategy
REEDS
F
I: 10-12 DAYS
ALTRICIAL
1 foot - 8 feet
(0.5 - 20 feet)
F
3-4
(2-6)
POLYGYN
F:11-14 DAYS
MF
SEEDS
FOLIAGE GLEAN
HAWKS
BREEDING: Freshwater and brackish marshes, riparian habitats, fields. 2, occ 3 broods.
DISPLAYS: Elevated on emergent veg, male spreads tail, droops wings, raises colored patches, fluffs feathers, leans forward with head pointing downward and "sings." Slow, stalling song-flight with tail spread, head down.
NEST: Near or over water, usu in emergent veg or shrub, rarely in low tree; woven of sedges, grass, lined with fine grass, rushes. Built in 3-6 days.
EGGS: Pale bluish-green, marked with dark colors. 1.0" (25 mm).
DIET: Includes few spiders; grass and forb seeds, rarely fruit. Young fed 100% insects.
CONSERVATION: Winters s to Costa Rica. Frequent cowbird host. Late summer and fall flocks occ damage grain crops, esp in mid-west.
NOTES: Strongly territorial on clumped territories. Marsh Wrens often puncture and occ steal eggs. Young can swim at 5-6 days. In addition to large fall and winter roosts, males may roost together in early summer. Males often form fall flocks separate from females and young; flocks often feed in uplands, roost in marshes. Enormous mixed winter flocks with grackles, Rusty Blackbirds, starlings, and cowbirds. Possibly most numerous N.A. land bird.
ESSAYS: Polygyny; Red-wing Coverable Badges; Visual Displays; Communal Roosting; Sexual Selection; Cowbirds
REFERENCES: Orians, 1980, 1985; Ewald and Rohwer, 1982; Yasakawa, 1979.
Help
Abbreviations
Species-Alphabetical Order
Species-Taxonomic Order
Essays
Except for Stanford Notes, the material in this species treatment is taken, with permission, from The Birder's Handbook (Paul Ehrlich, David Dobkin, & Darryl Wheye, Simon & Schuster, NY. 1988).