I headed off to look for other birds, and after a fruitless hour or so, spied an adult female displaying over the pines. This was a real treat as the bird was pretty close and flew lazily along over her territory, with stiff, harrier-like wings, and huge white puffball undertail enhanced by her tightly closed dark tail. She flew up and down a couple of times, before heading off west. Cracking!
A bit later, I retraced my steps and soon saw one of the immature females together with the gap-winged young male over the ridge. A Peregrine appeared and clashed with the female Gos, at one point chasing her rapidly down the slope - pretty brave as she dwarfed the falcon! She landed out of sight in the trees and the falcon headed off high. The male Gos in the meantime headed straight across the valley towards me and past by within 100 metres or so, providing stunning views through the scope.
Back to my starting point and I had brief views of an adult Gos which I took to be a male due to his size. He glided along the top of the pines before landing out of sight. Nearby, an adult female Gos suddenly appeared chasing one of the immature females. Due to the whiteness of her underparts looked almost like a different species from the immature she was chasing. She chased the young bird persistently all the way along the ridge and into the distance. Presumably these adults are trying to clear last year's young out of their territories.
Also seen today were about six Buzzards, some Golden Plover and plenty of singing Skylarks and Siskins.