From the blog underneath the video.
03/07/2020. 7:49
Although the kaba hen was around the nesting box yesterday, the couple did not sleep inside the nest. The hatching started yesterday morning, the result of which, the first pocket egg is already visible!
Laying of eggs is expected to continue, the litter can be expanded by up to 3-4 eggs. In recent years, this pair has spent several times in this artificial nest: one time three kaba chicks flew out, the other year only one, as the breeding was threatened by the constant clashes with the red bloodsuckers, from which the jackets eventually emerged victorious. Like the squirrels, for the most part the hen will hatch, but she will be replaced by the male at intervals, while the hen will move her muscles in a short flight.
In the case of falcons, the similarity is so great that they can only be distinguished from each other by their size (the hen is slightly larger than the male).
I wonder what the 'red bloodsuckers' are?