This video compresses days 20 to 32 in the lives of three Peregrine Falcon eyasses (chicks) nesting in the PG&E building in downtown San Francisco. See photos and visual logs of the young San Francisco Peregrines in local photographer Glenn Nevill’s Raptor Galleries. And learn more about the Peregrine Falcon research at the website of the Santa Cruz Predatory Bird Research Group Project (SCPBRG).

Our little Peregrine Falcon named Hi — the young tiercel (boy) in the brood — fledged yesterday from the 33rd floor of the PG&E Building in San Francisco. And just hours after he first took flight, he perished tragically in a collision with a high-rise window at Howard and Beale Streets. (Hii is the Coast Miwok word for “sun.”)

The messages of mourning continue to pour in on the listserv which monitors the San Francisco nest and its falcon folk. Anyone following the SCPBRG Falcon Camera saga in San Francisco had a day punctuated, initially, by elation as Hi — the first chick to fledge — was found on a ledge after being MIA for a time. Then, a sudden and devastating thump to the heart as we learned Hi had died instantly after hitting a window.

Owing to multiple nests in the area of the Peregine nest, Hi encountered some protective gull and crow parents, guarding their own young. It appears that in his efforts to navigate his own flight and his own landings, he also had to contend with pursuit by other understandably agitated bird parents. All the while, his parents, Diamond Lil and Dapper Dan were looking out for him and fending off potential assaults by other birds. But this complex navigation is most probably what led him onto a flight path that ultimately ended with the stark plate of glass.

Birds and Window Collisions

Window collisions are a significant source of mortality for birds and entire avian populations.

New York City Audubon estimates that between 100 million and 1 billion birds die each year in the United States from window collisions. Compare that against an already atrocious number of animals killed by cars (400 million or so) and more than 200 million killed by hunters. That puts the birds-and-windows number in dramatic perspective. A report by the American Bird Conservancy says that “collisions with buildings are now considered to be secondary only to habitat loss and degradation as a major source of anthropogenic mortality for birds.”

Window collisions are, of course, among the many injuries we see at the wildlife hospital where Hugh and I volunteer. During one shift, a casualty arrived in the form of a predator and prey: a Cooper’s Hawk and a waxwing he’d been chasing both collided with an acrylic basketball backboard. Both, again, died instantly.

There are measures we all can take personally to reduce the reflective nature of our windows or eliminate the other effects that lead birds to believe they can pass through the glass to the other side. On a commercial level, New York City Audubon recently published Bird-Safe Building Guidelines (thanks to Glenn Nevill for the reference) — which deals with architectural adjustments commercial builders can implement to deal with this monumental problem. This document also describes precisely why windows and glass are so problematic for birds, and why the collision rate is so high.

Rest in Peace, little Hi. You have taught so many of us so much in the context of your short and public life. I hope that awareness such as the buzz generated by the Santa Cruz Predatory Bird Research Group programs and the web cameras continues to permeate in a way that eventually renders us all a bit softer and more easily moved by the hardships of our wild brothers and sisters — a bit more attuned to the many lives which revolve around ours, even when its easy to remain oblivious to that alternate universe.

More information on Peregrine Falcons: