Nature Bulletin No. 163-A October 3, 1964
Forest Preserve District of Cook County
Seymour Simon, President
Roberts Mann, Conservation Editor
A blackbird is a black bird that walks like a man. It doesn't run a few
steps, like a robin, nor hop like a sparrow. It walks. Two kinds of them
are abundant in this Chicago region: the Redwing Blackbird and the
Bronzed Grackle. Another kind, the Cowbird, is fairly common. Most
abundant, especially in cities and residential areas, is that so-called
"blackbird", the Starling.
The Redwing is a marsh dweller. The males are among the earliest
birds to arrive here in spring, much earlier than the females, and then
we hear their joyful calls described variously as "gurgle-leee", "conk-a-
reee", or "the sound of an iron gate swinging on a rusty hinge." On
each shoulder they have an epaulet -- a scarlet patch fringed with
yellow. Their mates, unlike the females of other blackbirds, are heavily
striped. Their nests are loosely woven baskets suspended amongst rank
growths of cattails or sedges.
Another marsh dweller, closely related, is the Yellow-headed
Blackbird. The male has a conspicuous white wing patch and in spring
his head, neck and chest are bright yellow. Formerly, great colonies of
these spectacular birds nested in the vast marshes around Lake
Calumet, the Skokie Marsh, and other wetlands in Cook County, but
they dwindled until, this year, there was only one pair: at McGinnis
Slough in the Palos preserves.
Largest of all blackbirds -- largest of all songbirds except crows and
ravens -- are the grackles or 'crow blackbirds" that "strut like a lord. "
The Bronzed Grackle and the Purple Grackle are closely related but
the latter is rarely found west of the Appalachians and the male's back
is purplish, whereas that of a Bronzed Grackle is bronzy. Both have
iridescent plumage most conspicuous on the head and neck. Both have
yellow eyes and a long wedge-shaped tail. The tail has a crease in the
center and sometimes, especially in spring, has a keel-shaped
appearance. The females are smaller than the males and their plumage
has less of that metallic sheen .
grackles nest in colonies and all sorts of places. Tall dense
evergreens are favorite locations but here in Cook County they also
nest in small trees such as hawthorns, and one colony nests beneath
the long bridge across the Des Plaines River on US 45. They have a
reputation of being cannibals who destroy the eggs and helpless young
of other birds, but that has been unjustly exaggerated.
The Cowbird is a unique blackbird. It is smaller than the other kinds
and its bill is sparrowlike -- relatively short and conical. The male is
the only blackbird with a brown head and neck; the female is brownish
gray. She builds no nest. Surreptitiously she lays her eggs in the nests
of smaller birds -- usually one egg in each nest -- and then forsakes
Originally, this species followed the vast herds of bison that roamed
the Great Plains, feeding upon ticks and insects which infested them
and insects disturbed by their grazing, as well as the seeds of grasses
and other prairie plants. The cowbird roamed as the buffalo roamed.
Some say that is why it became a parasite like the European cuckoo.
Two other kinds of blackbirds may be seen here during their
migrations or, in small numbers, during winter: the Rusty and the
Brewer's -- smaller than grackles and having shorter tails. Both have
yellow eyes and, except in strong sunlight, appear to be all black. They
are very similar but the Rusty nests in swampy woodlands far north,
whereas the Brewer's is a prairie species.
The Starling, a chunky short-tailed distant relative of the blackbirds,
walks with quick erratic steps. Introduced from Europe during the
1890's, it multiplied enormously and has become a pest from coast to
coast. See Bulletin No. 140.
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Update: June 2012