This video is called An evening flight of a Hen Harrier [male].
The Werkgroep Grauwe Kiekendief in the Netherlands reports on Monday 23 June 2014 that ever since 2009, hen harriers nest in fields in Groningen. Hen harriers are very threatened in the Netherlands. They used to nest on Wadden Sea islands, but have declined much there recently.
In the Groningen fields, hen harriers meet a related species, Montagu’s harriers. Montagu’s harriers became almost extinct in the Netherlands 25 years ago, but managed to survive because of pro-nesting measures in the Groningen fields.