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Field
Guide IDs: BREEDING:
Woodland, forest
(esp decid), forest edge, grassland. DISPLAYS:
Courting male
ruffles feathers of upper body, bows toward female,
and calls. In air, male ruffles feathers as on
ground, bends head, arches wings and sings. On
elevated perch, male points bill straight up,
fluffs feathers on nape, breast, and flanks, sings,
then arches neck, spreads tail, raises wings, and
bows. NEST:
Does not build
nest; deposits eggs in nests of other species, esp
flycatchers, warblers, finches, and
vireos. EGGS:
White to
grayish-white, marked with browns. 0.8" (21
mm). DIET:
Includes spiders,
few snails; grain, grass and forb seeds. CONSERVATION:
Winters s to s
Mexico. Range has expanded e and w from Great
Plains with clearing of forests and introduction of
cattle, with which it is now assoc (originally
assoc with American bison). NOTES:
See
Cowbirds.
Highly gregarious at all seasons; postbreeding fall
flocks generally 50-200. Feeds and roosts in
enormous flocks with other blackbirds and
starlings, esp in winter. Fairly common
breeder in a variety of habitats virtually
throughout campus, less common during the
nonbreeding season. Laying its eggs in the nests of
other species, the Brown-headed Cowbird has been
observed parasitizing the California Towhee (the
most frequent cowbird host) and [OBSERVERS ADD
OTHER SPECIES] on campus. ESSAYS: Brood
Parasitism;
Conservation
of Kirtland's
Warbler;
Communal
Roosting;
European
Starlings;
Range
Expansion REFERENCES:
Darley, 1982;
Friedmann and Kiff, 1985; Teather and Robertson,
1986. |
