Crows flock to members of their own species after death and may interact with the dead bird in a variety of ways. Although the behavior may look like mourning, scientists believe it serves other purposes as well. Crows are incredibly intelligent and maybe trying to learn from the situation at hand, trying to ascertain both what may have befallen their comrade, and whether they need to be on the watch for new predators.
As the incredibly clever birds they are, crows also share information and use these funerals as a way to both gather information and redistribute it amongst the group allowing individuals to respond and adapt to environmental changes immediately. Their ability to categorize the information gleaned from a crow funeral, or griefing, is critical to their survival that depends on differentiating friend from foe.