Here is some very interesting information about crows that I snipped from an article titled The Mystery of Animal Grief in TIME Magazine by Jeffrey Kluger:
Nobody feels cuddly about crows. They're too big, too loud, too mean. They scavenge with the greed of buzzards, prey without the grace of eagles and even chase down children who come too close to their nests. They are the dark symbols of human mythology--portents of plague, of sorcery, of evil. There's a reason the proper term for a flock of them is a murder of crows, and it's not because we like having them around.
But there's something deeper going on in the soul of a crow. An animal that inflicts death so readily seems deeply moved when one of its own kind dies. A dead crow lying in the open will quickly attract two or three other crows. They dive and swoop and scold--emitting a very particular call that summons up to a hundred other members of the flock. With near ceremonial coordination, they land and surround the body, often in complete silence. Some may bring sticks or bits of grass and lay them next to--or even on top of--the remains. Then, tribute paid, they turn and fly off.
"Crows form lifelong pair bonds and might be mated for 20 years," he says. "When one dies, we've seen the survivor just standing above it looking at it."