This 14 July 2017 video is about a pallid harrier nest in Groningen province in the Netherlands. There are only about 10,000 couples worldwide of this globally near-threatened species; most of them in Asia.
In Europe, so far they only nested in Russia and Finland. So, this Groningen nest is a unique first. There were five chicks in the nest. Four of them, all female, survived and fledged. They have all been ringed.
This video is about measuring and weighing the young birds.
See also here.
A few pallid harriers had been seen in the Netherlands before, but not as breeding birds.