I'm not sure but I would definitely fill out a lost item form.
My daughter lost her sunglasses somewhere in the park one day last year. At some point during that day, she told us that she didn't have them anymore so on our way out, we filled out a lost item form.
At least a couple of weeks passed and a package came in the mail. The addresses were hand-written but when we saw the Busch Gardens return address, we knew what it was. I opened it up and sure enough, there were my daughter's sunglasses.
I thought that was exceedingly cool.