Had a look at the slideshow, and as a project manager, my concern is the netting. It looks like pigeon exclusion netting, which is really the only way to keep pigeons off a building, particularly older buildings with their ornate architecture. And pigeon droppings are brutal on stone/brick, corrosive in fact, not to mention the health problems that can arise. For peregrines, I would have chosen something else, perhaps plywood sheets on an angle so she wouldn't have enough room to nest without the potential for her getting caught in the netting. If she should get caught, it is hoped that a) someone notices quickly and b) access to the site is available, which I assume is so since she has nested there before. And it wouldn't just be her, both birds could be caught.
Now, before y'all panic folks, peregrines are predators and predators, because they have to rely on their ability to catch things in order to survive, take fewer risks than say a prey species. Birds in particular, and raptors for sure, are very aware of how close they can get to things and when, without injuring themselves. If you watch that slideshow again, Mariah is actually a very savvy and adept little flyer, it looked more nerve-wracking to us than it probably was for her. But that doesn't mean she's safe, a gust of wind or a moment of inattention and anything can happen, just means that she's being careful and has the skill to keep herself out of trouble under normal conditions.
Help any?
