There are many spots the parents watch from that aren't visible on camera. Generally if the parents aren't right nearby they are escorting a potential threat out of the airspace.
The other day when the Nervous Nellies (myself included) got concerned it turned out Beauty was on OCSR (the 1st Federal building)...the round top building on the right edge of camera 4...about block away.
At natural cliff nests they are in danger from great horned owls, crows and ground predators but the urban nests are reasonably safe from all but humans.
OK...I'm done trying to count meals today...this is #12...leftover pigeon wing from 2nd lunch. Unless you count the scrap that Dot found in the box & fed them 2 bites...