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Cool Facts |
Photo
taken from:
The
Sibley Field Guide to Birds of Western North America by
David Allen Sibley
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- American Crows congregate in large numbers in winter to sleep in
communal roosts. These roosts can be of a few hundred, several thousand,
or even up to two million crows. Some roosts have been forming in the
same general area for well over 100 years. In the last few decades some
of these roosts have moved into urban areas where the noise and mess
cause conflicts with people.
- Young American Crows do not breed until they are at least two years
old, and most do not breed until they are four or more. In most, but not
all, populations the young stay with their parents and help them raise
young in subsequent years. Families may include up to 15 individuals and
contain young from five different years.
- The American Crow appears to be the biggest victim of West Nile
virus, a disease recently introduced to North America. Crows die within
one week of infection, and few seem able to survive exposure. No other
North American bird is dying at the same rate from the disease, and the
loss of crows in some areas has been severe.
- In some areas, the American Crow has a double life. It maintains a
territory year-round in which all members of its extended family live
and forage together. But during much of the year, individual crows leave
the home territory periodically. They join large flocks foraging at
dumps and agricultural fields, and sleep in large roosts in winter.
Family members go together to the flocks, but do not stay together in
the crowd. A crow may spend part of the day at home with its family in
town and the rest with a flock feeding on waste grain out in the
country.
- Despite being a common exploiter of roadkill, the American Crow is
not specialized to be a scavenger, and carrion is only a very small part
of its diet. Its stout bill is not strong enough to break through the
skin of even a gray squirrel. It must wait for something else to open a
carcass or for the carcass to decompose and become tender enough to
eat.
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Description |
- Size: 40-53 cm (16-21 in)
- Wingspan: 85-100 cm (33-39 in)
- Weight: 316-620 g (11.15-21.89 ounces)
- Eyes dark brown.
- Legs black.
- All feathers black glossed with violet.
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Sex Differences
Sexes alike in plumage, but male averages slightly larger.
Immature
Juvenile similar to adult, but head feathers not glossy and more
fluffy, inside of mouth red. Immature wing and tail feathers becoming
brownish over the course of the first year. |
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Range Map |
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Taxonomic Hierarchy |
© 2003 Cornell Lab of Ornithology
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Kingdom: |
Animalia |
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Phylum: |
Chordata |
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Subphylum: |
Vertebrata |
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Class: |
Aves |
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Order: |
Apodiformes |
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Family: |
Trochilidae |
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Subfamily: |
Trochilinae |
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Genus: |
Selasphorus |
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Species: |
Selasphorus sasin |
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Subspecies: |
- Selasphorus sasin sasin
- Selasphorus sasin sedentarius
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Sound |
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Common call a harsh "caw." Also a variety of rattles, coos, and clear
notes.
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Identification and
Information
See
Anatomy
of a Bird
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Length Range: 44 cm (17.5 in)
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Weight: 453 g (16 oz)
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Size: 4. Large (16 - 32 in)
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Color Primary: Black
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Underparts: Black with iridescent blue sheen.
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Upperparts: Black with iridescent blue sheen.
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Back Pattern: Solid
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Belly Pattern: Solid
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Breast Pattern: Solid
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Head |
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Bill Shape: All-purpose
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Eye Color: Steel gray to blue-gray in
young, turning gray, then brown, and eventually
dark brown at maturity.
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Head Pattern: Plain
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Crown Color: Black
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Forehead Color: Black
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Nape Color: Black
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Throat Color: Black
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Cere color: No Data
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Flight Pattern: Slow steady delierate direct
flight with deep wing beats., Glides with slight
dihedral from altitude to perch or ground, between
perches, and from perch to ground.
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Wingspan Range: 84-102 cm (33-40 in)
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Wing Shape: Rounded-Wings
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Tail Shape: Fan-shaped Tail
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Tail Pattern: Solid
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Upper Tail: Black with iridescent blue and green
sheen.
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Under Tail: Black
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Leg Color: Black
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Breeding Location:
Forest edge, Open landscapes, Grassland with
scattered trees, Streams, upland
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Breeding Type:
Monogamous, Solitary nester
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Breeding Population:
Abundant
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Egg Color:
Blue green to olive green with dark
markings
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Number of Eggs: 3 - 7
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Incubation Days:
18
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Egg Incubator: Both sexes
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Nest Material:
Branches and twigs., Lined with tree
material, grass, feathers, moss, and hair..
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Migration:
Some migrate
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Condition at Hatching: Naked except
for sparse tufts of grayish down, eyes
closed, clumsy.
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Other Names |
Similar Species |
- Corneille d'Amérique (French)
- Cuervo americano (Spanish)
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- Fish Crow very similar, but smaller and with a more
nasal voice.
- Northwestern Crow essentially identical, but with
more nasal voice.
- Common Raven larger, with longer and more curved
bill, shaggy throat feathers, more distinct "fingers" in the wings, a
wedge-shaped tail, and a deeper and more guttural voice.
- Chihuahuan Raven very similar, but with
wedge-shaped tail and different voice.
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Conservation Status |
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Populations slightly, but significantly increasing over last half of
20th century. Severe susceptibility to West Nile virus may cause
population decreases in near future. You can help scientists learn more
about this species by participating in the Celebrate Urban Birds! project. |
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Habitat |
Sources used to
Construct this Page: |
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Variety of habitats. Requires open ground for feeding and scattered
trees for roosting, nesting, and refuge. |
- McGowan, K. J. Frequently asked questions about crows. http://birds.cornell.edu/crows/crowfaq.htm.
- Verbeek, N. A. M., and C. Caffrey. 2002. American Crow (Corvus
brachyrhynchos). In The Birds
of North America, No. 647 (A. Poole and F. Gill, eds.). The Birds of
North America, Inc., Philadelphia, PA.
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Food |
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Omnivorous. Waste grain, earthworms, insects, carrion, garbage, seeds,
amphibians, reptiles, mice, fruit, bird eggs and nestlings. |
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Behavior |
Forages mostly on ground. Pecks from surface and digs through litter.
Caches food for later use. |
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