The little bunting (Emberiza pusilla)
In Slavic countries, this bird is called "Bunting-Crumb". Obviously this is due to hers small size, well, outwardly it looks like a crumb from a bun. It is difficult to see her, because she spends all the time in dense bushes, besides, she has a quiet and almost imperceptible voice.
The bird is very shy, and noticing the danger, she immediately hides deep into the bushes, moreover, she slowly moves away from the place where hid, thus it seems that she practically disappears.
By the way, these birds have not yet flown to warm countries, I saw them last week. And this is not surprising, because they are granivores, and can do without insects.
It was purely by chance that I was lucky to film this bird. I was hiding in the bushes to take pictures of the warblers, when this bird suddenly and imperceptibly appeared.