Strange things in the toilet?

Well, it all started a few days ago when a bale of hay appeared in my toilet. I didn't think it was a big deal, but the next day a weasel and a pencil sharpening gorilla came out and started to graffiti my bathroom.. Since then, there has been something new in there every time I check, radishes, alarm clocks, boulders, purple giraffes, salmon, finger paints, etc. What do you think is happening? Are they getting in through the sewer system or something?