I spoke to the Ranger putting up the restriction signs yesterday. The Falcon who normally nests on Hen Cloud couldn't get to that nesting site because of the snow, so has returned to the Black and Tans area of the Upper Tier. - about two thirds up.
The restricted area runs from Damascus Crack to Easy Gully which for those not in the know pretty much includes all the Upper Tier 'classics' - Sloth, Sauls's Crack etc and also includes all the upper tier boulders apart from 'Bancrofts 6b block' - thought this was a bit much but apparently climbing around on top of the boulders interrupts the falcons flight path and may stop the falcons returning to the nest.
Cheers