I live only a few miles from Potteric Carr Nature Reserve, it's a place I've visited regularly in the past, mainly to photograph the Bitterns that stay over Winter there. As many as 6 have stayed for the Winter months, but eventually the birds move onto the continent to breed. It is hoped that in future the birds will stay on to breed.
I've spent many hours in the hides at the Carr, my favourite being the one at Piper Marsh, the birds are very secretive and difficult to spot and move like a cat, very slowly and with precision.
Some bird watchers have been going for years and have never seen one, fortunately for me nearly every time I went to the Carr, I saw one or even two. Bliss. Mind you, these photographs do represent hours and hours of sitting in a hide.