I assume the bird tries to break open the “eggs” it found. I know, boring explanation for an absolute funny video.

And he is so eager doing so. Looks like the most important task all day with him runnig up to the path. He puts everything he got into smashing that ball onto the concrete as hard as he possibly can and is all fluffed up when that thing inevitably comes down again to nearly hit him. Almost like a toddler.

This is a bird called the Sereima, and what you are seeing isn’t random behavior: it’s how they hunt. They chase rodents and lizards down, grab them with their beaks, then slam their prey down onto rocks repeatedly until they stop moving.

Metal as hell.