Every bird-watching guide describes the American Crow as one of the most intelligent birds.
Other adjectives used to describe this bird are resourceful and mischievous.
Any way you describe them, these birds are worth watching as they go about their nesting and feeding habits.
One commonly seen habit of these birds is called "mobbing".
When you hear them giving harsh, drawn-out caws and see them diving into treetops, chances are there is a hawk or owl in the tree.
The purpose is to drive off what they know is a predator of their young.
Even if the intruder leaves the area, the crows will continue to chase after it for a while longer, making sure it's gone from their territory.
One reason for this behavior, other than just chasing predator birds away, is to teach their young who their predators are.
According to the PBS Nature Program "A Murder of Crows", (link to DVD below), these birds may be able to distinguish between one human and another.
Crows may be able to communicate to others whether a certain human is to be feared by recognizing features and remembering past actions.
The American Crow is 17 to 21 inches in length. All black with a fan-shaped tail.
Both males and females are similar in appearance. The Crow's voice is the best way to distinguish it from other all-black birds.
The voice is a long, descending "caaaw". Although it has a variety of other calls which are important to its system of communication.
The mating breeding habits of the American crow takes place on the ground. Crows begin mating around mid-March.
The males have a courtship display which consists of facing the female and fluffing their body feathers out.
Then he partially spreads his wings and tail and proceeds to bow repeatedly while uttering a brief rattling song.
Once a male and female have mated, they perch together and may touch bills and preen their mates feathers.
This mating behavior may not be seen very often because Crows mate for life.
Pairs already mated do not usually have courtship displays.
Pairs that are unsuccessful at breeding will part ways and return to their families.
Should a mate die, the surviving mate will attempt to find a new mate at some time.
Crows also demonstrate cooperative breeding. This is when the previous year's young help raise the newest brood.
You can read more about cooperative breeding in our article here - Helper Birds
It's not unusual for males to wait a few years before mating.
Crows are very secretive around their nest. While noise is a mainstay of its behavior in other areas, the nesting site is quiet.
Nesting can begin as early as March; construction of the nest takes about 2 weeks to complete.
Spring storms can destroy nests. This may cause nest construction to last through June.
Sometimes difficult to find, the nest is placed 18 to 60 feet above the ground in a tree near the trunk.
Made of twigs and sticks, lined inside with bark, grass, and moss. The nest is about 12 inches in diameter.
Crows do not use the nest in winter. They will roost or sleep in large numbers in a group of trees.
Most nest are abandoned after a single use, although a new nest may be built next season in the same tree.
A typical American Crow nest can be seen in the picture below.
The female lays 3 to 7 eggs that are bluish-green with brown marks.
Incubation (gestation period isn't used for birds)is primarily done by the female with the male close by and sometimes feeding her.
The eggs will hatch after 18 days of incubation.
The young are born blind and flesh-colored. After about five days, their eyes will open for the first time.
Both parents feed the young, receiving help from previous years young.
At five weeks of age, the fledglings will leave the nest. The parents will continue feeding them for a while after leaving the nest.
Only one brood a year is raised. If nesting is interrupted, they may attempt to re-nest.
Young males will return to their parents if their first attempt at mating and nesting is unsuccessful.
The diet of Crows consists of insects and small reptiles. They will also eat eggs and nestlings of other birds.
Included in their diet are carrion, fruit, and crops such as corn.
Crows tend to be opportunistic feeders, eating whatever is available.
During the nesting season of other songbirds, you may not want to use bird feeders if you have Crows around.
They will find a songbird nest and feed from those nests.
Crows are the wariest while feeding. Feeding in flocks of 5 to 7 birds, they will arrive on their feeding territory, landing in the trees.
While most will begin feeding on the ground, one or more will remain in the trees watching for predators.
Cracked corn and sunflower seeds will attract these birds, although about any kind of seed will be eaten by them.
In fall and winter, the American Crow roost in large flocks, numbering sometimes in the thousands.
Each day in the late afternoon, the birds begin flying along fixed routes to pre-roost sites, gathering with other flocks and moving to the final roost.
They may fly as far as 50 miles every day to join the roost.
Once there, they quiet down for the night, waiting for dawn to fly back to their feeding territories.
I'm asked from time to time why crows fight with each other, even to the death.
Sometimes it's as simple as not being a family member.
While they are social birds, those not of the family may be chased away to protect territory or mates.
It may seem cruel, but sometimes a sick, injured or otherwise physically compromised bird may be attacked by others.
Weak animals are always at risk from predators. These birds may have some sense of that vulnerability.
Another question that comes up is, why do they moisten their food in birdbaths and other water sources?
The truth is, no one knows for sure. Theories exist. Some believe they are cleaning their food.
Since crows are intelligent opportunistic feeders, eating food from human trash and landfills, it's believed by some that they've evolved to clean their food before eating.
Another thought is that they use water to moisten dry food and soften hard food types such as peanuts.
Still, others believe crows dip their food to provide moisture for the nestlings during the nesting season.
This would provide water to the young while still in the nest. See, How Baby Birds Get Water in Nest.
Each theory is plausible, but as stated, it's not known for sure.