A rain of tadpoles?

The Japanese newscasters are mostly playing it for laughs, but apparently some people here in Japan are having mysterious showers of tadpoles. Now, at this time of year, we do have lots of tadpoles in the rice fields, but how are they getting from there to . . . one person had a pile in front of their garage. Someone else had them turn up on the second floor balcony.  The two explanations being advanced are birds and winds. But birds normally don't drop their food -- or if they do, they go back and pick it up.  And no one seems particularly convinced that we have little tornadoes picking up tadpoles and then dropping them in selected locales. So far I haven't heard anyone suggesting that there might be kids laughing, although that also seems possible to me. But then, I grew up in America where kids are perhaps a bit more prone to pranks  such as this.

I'm wondering what thinks that humans can be propitiated with a suitable offering of tadpoles. Unidentified Flying Tadpoles?  A rather odd, if minor, mystery.