Crows are one of our most common urban wildlife residents. These omnivorous birds will eat just about anything, including fruits, vegetables, insects, small rodents, and even other birds and bird eggs. Given the opportunity, they will also raid garbage cans.
Crows are protected under the Migratory Bird Act of 1918. It is illegal to harm a crow or to destroy an active nest. It is also illegal to have a crow as a pet. Only facilities that possess federal permits to use crows for educational purposes are allowed to keep crows in captivity.
- Crows typically build a stick nest in a tall tree, but may also use ledges of man-made structures.
- Nest building occurs in late April and May. Crows lay 3-6 eggs, which are incubated for 18 days. The young remain in the nest for 28-35 days. It is common for youngsters to leave the nest before they are able to fly.
- During this time, both parents as well as offspring from the prior year care for youngsters. Young remain with the parents throughout the first year of life and help raise the following season’s offspring.
- Crow families will establish territories during the breeding season, but during the non-breeding season they gather at huge communal roosts, or sleeping areas.
- Communal roosts can be as large as several thousand crows. During the day, crows disperse to forage and return to the roost in the evening.
Common Situations or Concerns
Fledgling Crows on the Ground
Like many species, juvenile crows will typically leave the nest before they are able to fly. They will spend several days on the ground building up their flight capabilities and learning essential survival skills from their families. This is a completely normal and very important part of their life cycle. It is not uncommon to find young crows on the ground in suburban, urban and industrial areas during the months of May, June, and July.
Fledgling crows are as large as adults, and people are frequently concerned that the crow they have seen on the ground is an injured adult rather than simply a youngster learning to fly. One easy way to tell if a crow is a juvenile is to look at the color of the bird’s eyes. Young crows have blue/grey eyes, while adults have black eyes.
Unless these birds are clearly injured, they should be left alone for their parents to care for. Crows that are in immediate danger can be placed up off the ground on a low branch or structure, but should not be moved more than 100 feet from where they were found.
Although the urban landscape may seem like a hazardous play for a crow to grow up, remaining under parental care is still the best thing for the youngster – crows spend between one and two years with their parents, learning complex life skills that are required to integrate into the species’ complex social structure. Captive-raised crows don’t have the benefit of parental guidance, and face many more challenges than their wild-raised counterparts.
Crows Are Making a Ruckus Near the Fledgling
Crows are very protective of their young and will bring food to the youngster, attempt to direct it away from harm and drive off potential predators. The family may not always be present but are usually close by.
Sometimes protective behavior by adult crows can be confused for aggression against the youngster, but rest assured that a loud, raucous group of adult crows is a sign that a youngster is in good hands.
Aggression Towards Pets and Humans
Both pets and humans are far beyond the size of crow prey. Aggression is almost always the result of adult crows protecting nearby young and is limited to a very small area. It is a temporary situation that is best resolved by trying to avoid the area they are protecting. While it can be intimidating, crows rarely present a threat to humans, dogs or cats.
Unwanted Crows in the Neighborhood
Crows can sometimes be deterred from roosting or foraging in a given area. Loud sudden noises such as banging pots and pans together just before sunset can be effective in disrupting a roost location. There are also companies that sell distress calls. Scarecrows do work but only in a small geographic area, and if they are built such that they move in the wind and are accompanied by some sort of noisemaker. Tightly covering garbage and compost will help reduce attractants.
Crows Raiding Other Bird Nests
Crows will prey upon small birds and will consume other birds’ eggs. While this may be difficult to watch, it is entirely natural and there is no reason to intervene. Similarly, crows may themselves be preyed upon by larger predators such as Red-tailed Hawks and Great Horned Owls.