Many years ago, I watched a documentary about some guy who designed unusual bird feeders in his yard. Over time, the guy kept changing them--adding various steps the birds would need to complete in order to get their food rewards. I was shocked how complicated these steps became...and how easily crows learned and adapted to these puzzles. Because I loved this film*, I decided I had to watch "Nature" when they aired the episode "A Murder of Crows"**. Despite the ominous title, the film is not about killing the birds but about their intelligence--and how, in some ways, crows are about the smarted creatures on the planet aside from people (or, at least MOST people).
This show discusses many crow behaviors that would seem to indicate that this animal is extremely intelligent. Of course, the show discusses puzzles and the use of tools like the older documentary, but it also shows that crows can recognize faces after more than two years, learn some tasks at about the same speed as small children, communicate with each other in many ways and to relay many different things, create FALSE food stashes in order to fool other birds that might be watching them, and many other surprising signs of great intelligence. All of this is exciting stuff--especially for animal behaviorists, psychologists, ethologists and other researchers. But, it also is great stuff for the average viewer, as I know my aunt saw this film and loved it--and she prodded me to watch it (which she didn't need to do very strongly)! Exciting and well worth your time.
*I have searched IMDb several times to try to find this show from about 1988 or so, but have had no success at all. If you might know more, please let me know. Thanks.
**Oddly, a group of crows is called a 'murder'. Why? I have no idea! We have pods, gaggles and schools of various animals...so why call a group of crows a murder?!