This video is about nightjars in Sweden.
From BTO Bird Ringing blog in Britain:
Last year UK ringers caught over 230 Nightjars to try and find out more about their fantastic migration and demography. This species is believed to winter in tropical and South Africa. So far we have received recoveries from various countries including The Netherlands, Spain, France, Morocco and Algeria but there is much more we don’t know yet.
Red-necked Nightjar sound-recorded in Belgium last summer: here. 1st for Belgium.
Bird ringing in Britain: here.
June 2011. Capturing birds using mist nets to study behaviour, movement or the demographics of a species is one of the most common research techniques in ornithology, yet until now there have been no large scale studies into the risks mist nets pose to birds. Writing in the British Ecological Society’s Methods in Ecology and Evolution researchers from California used a dataset of over 345,000 records to evaluate the risks of mist netting: here.