Mentioned on Autumnwatch the other day that they seem to have disappeared - Chris P suggested they might be unseen flying high...............
My first spots were the influx in late summer, lots at 1500ft + here in the pennines, so they do fly high.
Also, in Greece two weeks ago, abs loads on Alonnisos, Sporades islands, just like our summer surfeit over here, but still having a warm time in the sun!
Perhaps they were all on holiday too?
Cheers
Ken