Years ago a friend and i were sitting on a rock next to a house, we were about to eat, he had brought lunch in a brown bag, set it down then walked off to his car. A crow came down, right in front of me and grabbed it, flew up to the peak of the roof and ate his lunch, inaccessibly, in front of him. I thought that displayed quite a good bit of intelligence and rakishness. Currently i have a troupe of Ravens that reside in the woods out front. I often wake to their croaky calls and we frequently chat out in our shared turf. Maybe i get more out of the conversation than they do, IDK.
I was recently in the canyon-y Southwest, where Ravens and i would frequently watch each other. It was interesting to see them choose just the perch I had in mind for myself had i been where they were headed. They know what's up, i'm convinced.
I've read Lawrence Kilham's On Watching Birds but he wrote The American Crow and Common Raven which I've not yet but it looks really good:
https://www.goodreads.com/book/show/97572.The_American_Crow_Common_Raven?from_search=true
".....This book explains especially the social systems of these birds, from cooperative breeding to predator mobbing. Difficult topics such as 'play' and 'thinking' in crows are interestingly and critically presented. . . . an appealing volume." --Choice " . . . his book is one of the best, most informative and engaging ones yet written about how some of these birds live, think, and feel. Kilham on crows compares favorably with Tinbergen on gulls, Goodall on chimpanzees, and Lorenz on dogs and jackdaws." --Smithsonian "