How a WashU professor used concrete to build a 20-foot-tall home for migratory birds

A 20-foot-tall concrete spiral was recently completed at the Audubon Center at Riverlands nature reserve near St. Louis. The structure's practical use will be as a bird blind — a temporary home for migratory birds. But there’s something else that’s fascinating about this structure: A novel method of shaping concrete. To get to the bottom of this spiral (and inside its concrete walls) we talk with Pablo Moyano Fernández, associate professor of architecture at WashU’s Sam Fox School of Design & Visual Arts. Moyano Fernández is the creator of that structure, called "Avis Spiralis."