I've always liked this tidbit from a family that regularly feeds peanuts in the shell to the local crows.
>she lost a lens cap in a nearby alley while photographing a bald eagle as it circled over the neighbourhood.
She didn't even have to look for it. It was sitting on the edge of the birdbath.
Had the crows returned it? Lisa logged on to her computer and pulled up their bird-cam. There was the crow she suspected. "You can see it bringing it into the yard. Walks it to the birdbath and actually spends time rinsing this lens cap."
Bengt Heinrich, writing in "Mind of the Raven", found their limit by tying bits of meat to strings hanging where they could reach the string. Some, not all, would grab the string with their beak and tuck it under one foot, and keep drawing it up until they got the meat. But none ever figured it out if the string was hung over a branch so they had to pull down to bring the prize up.
I once watched a scrub jay (who had a feud with the local squirrel) very deliberately lay a peanut vertically in mulch, tap it into the ground, and lay a large square of bark over top. It was very pleasingly methodical bird.
>she lost a lens cap in a nearby alley while photographing a bald eagle as it circled over the neighbourhood.
She didn't even have to look for it. It was sitting on the edge of the birdbath.
Had the crows returned it? Lisa logged on to her computer and pulled up their bird-cam. There was the crow she suspected. "You can see it bringing it into the yard. Walks it to the birdbath and actually spends time rinsing this lens cap."
https://www.bbc.com/news/magazine-31604026