Usually, our offices are just offices. Occasionally, we get a reminder that we sit in a totally unnatural aerie-for-humans, seven stories above the floor of the northern Willamette Valley.

This week, the epochal face of Nature belongs to this peregrine falcon, which has taken to hanging out on one of the fire escapes here at the Pittock Block.

Seeing birds of prey in urban settings always brings on a heady mix of emotions: there's the elemental joy of spotting a creature of such sculpted beauty, mingled with the reflexive, animal frisson of encountering a killing machine perfected by evolution. A glimpse of an airborne falcon, cruising over the city's grid and decoding its protein potential, both allows us a moment of Jonathan Franzen-style avian contemplation and turns each of us, at least for a second, into a rabbit in the grip of an existential crisis.

In the specific case of peregrines in Portland, there's also the all-too-rare opportunity to appreciate an environmental success story. As the Audubon Society of Portland reports, the birds were "once one of the most endangered species on earth." But—who could see this coming?—actual regulatory and conservation efforts were undertaken, including the 1972 ban on DDT and Portland Audubon's own on-going project to foster the species here. Now the peregrines appear to be thriving, with Audubon reporting 11 known nesting sites within the city of Portland, and at least some evidence that an urban environment is actually good for the birds.

Our new friend, certainly, looks to be in fine health.