The rest of the year, they prefer to flock up with other crows for at least part of the day, often roosting in huge groups at night. If you watch at dusk, you can see them fly in long lines towards their night roost. These communal roosts may have some benefits, but they also have drawbacks. Roosting with other birds may protect them by sheer numbers from predators as there are more birds to be on the alert. However, that can also backfire as having too many birds also makes them more noticeable by predators.
Crows are primarily scavengers, eating whatever they can find off the ground.
They will hoard or hide food for times when it is not as plentiful. Common Crows eat insects, fruits, grains, nuts, eggs and nestlings, small rodents, carcasses and garbage. Northwestern Crows tend to spend time on the beach at low tide and also feed on small marine invertebrates, fish, crabs, clams and seabird eggs. Clams and mussels are opened by dropping them from a height onto rocks. Young crows are fed mostly insects such as grubs, cutworms and other invertebrates such as earthworms.