https://www.youtube.com/watch?v=TtYCMkyRaa4

I can't believe I was able to get this video! He spent such a long time on getting these colored pens out of the jar and onto the floor.

He's so busy! I love the color of his cheeks!

They're always into something aren't they?

Yes, indeed.
I have to say, it's really been interesting to see how much better he gets at taking the pens out and getting them onto the floor.
The first pen he actually got completely out of the jar probably took him half a day, with breaks in between efforts. It gets easier as there are less of them in the jar, so he emptied them all out over about an hour or two. Today, the process has gotten even faster.
This is really the best game ever! He gets them all onto the floor; I pick them up and put them back; he gets them all onto the floor again.
I don't mind picking them up. It's so great to see him so entertained. I wonder how long the fascination will last.

This is called avian fetch. The bird throws things for you to retrieve, so it's the opposite of dog fetch. I don't think they ever get tired of it.

Avian fetch. I might have to try that with Lucy, especially on her hyper days.

Those light plastic balls made for cats with jingle bells inside are big favorites for playing avian fetch. I have to pick them up off the floor every day. They're really cheap too.

I wonder whether there is anything adaptive about this in the natural environment. I can't think of anything.

Well one thing I know, is that a common behavior in parrots is to disperse their food for the "land mammals", but that usually apply to tree-feeding species.

Funnyyou should mention Carolyn, I actually have something similar to those. They were originally part of a bird toy, though the four cockatiels I had took it apart.

Lucy likes to throw her nutri-berries around while she's eating them, and since they'll sometimes fall off the bed or couch, I end up playing avian fetch with her.

In nature, do cockatiels eat on the ground or in trees?