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General: The
American Crow (Common Crow) is a common bird found throughout much of North
America. They can be spotted in
forests, farmland and cities. In the Northeast US I have watched American
Crows gather in large communal roosts at night. In the Capital District of
upstate New York (Albany, Troy and
Rensselaer) 10s of thousands of these birds roost along the Hudson River in
winter. During these roosting periods, it is common to drive just at
twilight and see branches of trees totally covered with crows. This scenario
is repeated in other towns and areas throughout their range.
The American Crow is an intelligent and adaptable bird.
It is one of only a few species of bird that has been observed modifying and
using tools to obtain food.
They are also an
aggressive bird and will protect territory, food and nests from almost all
intruders. It is common to see American Crows chase larger birds such as
hawks, falcons, owls and herons. I have watched as a mob (that is what a
flock of crows is called) of crows attack squirrels and mink.
When nesting, both members of a breeding pair help
build the nest. They make the nest with twigs with an inner cup lined with
pine needles, weeds, soft bark, or animal hair. Nest size is quite variable,
typically 6-19 inches across, with an inner cup about 6-14 inches across and
4-15 inches deep. Crows typically hide their nests in a crotch near the
trunk of a tree or on a horizontal branch, generally towards the top third
or quarter of the tree. They prefer to nest in evergreens, but will nest in
deciduous trees when evergreens are less available.
The female lays 39 eggs that are 1.4 1.9 long 1
1.2 wide. The eggs are pale bluish-green to olive green with blotches of
brown and gray toward the large end.
American Crows
are highly susceptible to the West Nile Virus.
Identification:
American Crows are generally 15.7 20.9 long with a wingspan of 33.5
40.0 and a weight of 11 oz 22 oz. The American Crow has iridescent black
feathers all over. Its legs, feet and bill are also black. They are
long-legged, thick-necked with a heavy, straight bill. In flight, the wings
are fairly broad and rounded with the wingtip feathers spread like fingers.
The short tail is rounded or squared off at the end.
When not sure if you are viewing a crow or raven
remember, the American Crow is about two-thirds the size of a Common Raven
(Ravens can be almost the size of a Red-tailed Hawk). And Raven tails in
flight are wedge shaped.
Habitat:
Virtually all types of country from wilderness, farmland, parks, open
woodland to towns and cities are inhabited; it is absent only from Pacific
temperate rain forests and tundra habitat where it is replaced by the raven.
Territory:
The range of the American Crow extends from the Pacific Ocean to the
Atlantic Ocean in Canada, on the French islands of Saint-Pierre and
Miquelon, south through the United States, and into northern Mexico
Migration:
This crow is a permanent resident in most of the USA, but Canadian birds can
migrate some distances southward in winter.
Diet:
American Crow is omnivorous, usually feeding on the ground and will eat
almost anything. It will feed on invertebrates of all types, carrion, scraps
of human food, seeds, eggs and nestlings, stranded fish on the shore and
various grains. American Crows are active hunters and will prey on mice,
frogs, and other small animals. In winter and autumn, the diet of American
Crows is more dependent on nuts and acorns. Occasionally, they will visit
bird feeders. I often see them along roadsides feeding on road-kill.
I have read that though their bills are large, crows
cant break through the skin of even a gray squirrel. I have spent time
observing crows feed on a gray squirrel that had been hit by a car two days
earlier. They were able to break through the skin of the squirrel.
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