Hi Helle,

If it appears only in spring, so it can not be from Santa Claus.
Provided that, this guy in Denmark prefers springtime .:ohmy:

Now I think that it could be the shelling of a broken bird's egg.
And otherwise the feathers of a chicken or bird in moult, but that latest, I guess its 'nope', again!

But, as it would be a broken bird-egg, from which bird does this egg come, then?

From a strange bird, with difficult questions???