How did that get there?

I was cleaning up the kitchen and I had an empty bottle of creamer, so I stepped outside and tossed it into our recycling bin.

Then my children finished both the lemonade and the juice, so I had two more bottles for the recycling bin. I walked over to it and put them in and...

there was a dead mouse lying in the bin.

This is not something you expect to find in your nearly-empty recycling bin. I haven't seen any mice, live or dead, since we moved in. No mouse poop, no mouse noises, no mice. And now there was a dead one inexplicably lying in my recycling bin. Some water was in the bin... did it drown? It was about a millimeter of water. If it didn't die in the bin... who put it there? There's a random cat who wanders through our yard...

I need my daughter to get her magnifying glass out and look for clues, because I'm baffled.