They exhibit a cooperative defense behavior where they will often gang-up on or mob an enemy until it leaves the area. Man is the number one enemy of the crow. Habits Crows are very social and live in family groups of between 2 to 15 birds, averaging 4 birds. A group of crows is called a murder . Pecking orders are evident as in all animals.
Crows are territorial and are avid defenders of the same.
They operate from central positions called roosts where they gather just before dark after returning from feeding on normal flight paths called flyways. Why they roost together is not, conclusively, known but it is thought for communal protection from predators. Winter roosts are communal and hold the largest numbers. When roosts are located in towns they cause many problems especially when there are thousands of birds. Towns have fought them with firecrackers, propane cannons, repellants and, sometimes, chain saws.