We thought dragons were the only animals that flew over Wean Hall, but photographer Renee Rosensteel spotted this peregrine falcon high above the Pittsburgh campus.

Although these birds of prey occasionally startle unsuspecting pedestrians along Frew Street, they're no danger --- unless you happen to be a tasty pigeon.

Listed as a Pennsylvania endangered species, peregrine falcons can reach speeds of 40 to 55 mph in level flight and dive at up to 200 mph, making them the fastest birds in the world. There are only two known peregrine falcon nesting sites in the western half of the state --- atop the Gulf Tower in downtown Pittsburgh and at the University of Pittsburgh's Cathedral of Learning.

According to the Western Pennsylvania Conservancy, which tracked the falcons locally from the 1990s through 2008, the buildings are ideal nesting sites because they offer tall, secluded ledges, perfect for raising chicks --- and teaching them to fly. Pittsburgh's National Aviary now manages the local falcon recovery project.

Renee's photo also shows the new Gates Center for Computer Science nearing completion at lower left, and its location relative to Newell-Simon Hall, Wean Hall and the rest of campus. (Renee Rosensteel photo)