this guy has some absolutely amazing birds in flight shots
http://500px.com/paddler
As you say a great set of images. Looking closely though he says "taken in the back garden" I think he must have rig to attract and there is well defined catchlight in the eyes of the birds which IMO says he used flash and as the BG seems quite well exposed a slow sync operation to boot. So very well crafted technique to get such wonderfull pictures. Now where to buy a 'better beamer' flash modifier 
Note ~ seeing the limited EXIF data shown with a focal length of 80mm and 110mm and 120mm makes me wonder if he has a remote control rig with movement sensor trigger(s) I cannot quite see him getting that clse as he mentions full frame by using a hide???



Though with Mark & Kevin 'finding' it........ 
