After 20 minutes or so I caught sight of some movement, and there they were. They are really confiding birds and by perching myself on a rock, they carried on their business and came towards me. So many photographers don't use any field craft, but patience and good positioning means you never need to spook your birds and they in turn feel comfortable with you, which allows you to get your shots.
The male is darker, with the colouring almost black as opposed to the brown of the female.
Male on the left.