Communication can be quirky.
I spotted a hockey puck that had been lost in the bush and brought it out to the picnic table my neighbour set up nearby. I left it there wondering if anyone had a use for it. The next day when I came by on my walk the puck was still on the picnic table but in another place. So I moved it. The next day it was moved again.
I have no idea who has been playing this little game with me but I am enjoying the odd friendly communication. It's been going on for weeks.