Details on the American Crow

"Crows are perhaps the best-known birds on the continent" (Mahnken, 1996).  They are large, dark birds, reaching 18 inches in length.  They have been described as black, with a purple or green sheen when the sun shines upon them.  However, as I stated before, the crows in Grand Forks, North Dakota appear brown in various angels of sunlight. Otherwise, and almost always they appear black. I have not witnessed a sheen of purple or green on them.

Egg laying events occur only once during the breeding season (one brood), and several are laid.  Eggs are bluish to olive green and are covered in brown marks.  Females will keep the eggs warm for 18 days.  Nest are usually built in pine trees toward the top.  Nests are big and bulky, with twigs and branches.  Most of the nest seems to be arranged in a sloppy, chaotic manner. However, it seems that care goes into the making of the middle of the nest, which is cup-like and lined with soft materials, such as, grass, feathers, dog hair, and deer hair.  Crows will pull hairs right out of animals for their nests.

Crows engage in courtship behaviors.  However, "courtship among crows begins with fighting in the flock" (Mahnken, 1996).  However, things take a turn for the better.  "The male walks toward the female, bows, ruffles his feathers, and spread his wings and tail.  He lifts his head up and then lowers it.  It's all very courtly, and his lady is impressed (Mahnken, 1996).

Crows are known for their mobbing behaviors- "calling on gangs of crows together to harass a large hawk or owl on a perch or drive it out of the area.  Catches up to a soaring hawk and repeatedly drives on it from above, often forcing it down into the shelter of trees below" (Alsop, 2001).  However, as I've indicated previously, I've never seen this or any type of mobbing behavior in Grand Forks.

Crows eat a variety of foods, which is why the species has persisted well throughout time:  "fruit, insects, mammals, fish, carrion, will come to seed and suet feeders" (Tekiela, 2000).  Crows can contract avian pox and West Niles disease.  West Niles disease can have devastating effects on crow populations.  However, overall, the species seems to still be going strong.

Crows are highly intelligent, and very human like.  They can use tools and mimic human voices.  Crows of one family will pitch in and raise the younger ones:

"A family unit usually includes a mom and dad and several “kids” hatched in previous years, and can include up to 15 birds! They include goofy, immature one-year-olds and some adult sons and daughters. Sometimes these kids stay with their parents for more than five years. In addition to the nuclear family, crow groups sometimes include extended family members such as nephews, brothers, and half-brothers of the mom and dad. We’ve also seen crows “adopt” the kids of unrelated neighbors" (Townsend, 2010).

Crows are fantastic creatures.  There is so much more to them that this posting presents, especially language.  Much more on language will be coming, in the future!

 

 Crow and Flower- Grand Forks, ND; Taken by Sharon Lee Hudson

Sources

.  Armstrong, B.  Bob Armstrong's Nature Alaska, http://www.naturebob.com/ 

.  Alsop, F.J. (2001).  Birds of North America:  Eastern Region.  DK:  New York

.  Townsend, A. (2010).   The Young and the Restless:  Watching Neighborhood Crows, All About Birds.  http://www.allaboutbirds.org/the-young-and-the-restless-watching-neighborhood-crows/

.  Spruch, G.M. (1983).  Such Agreeable Friends:  Life with a Remarkable Group of Urban Squirrels.  Morrow:  New York.
.  Tekeiel, S. (2000).  Birds of New York:  Field Guide.  Adventure:  Cambridge, MN.

.  Manhnken, J. 1996.  The Backyard Bird-Lovers Guide:  Attracting, Nesting, Feeding. Storey Books:  Pownal, Vermont.