Design Traps for Birds

True or false? Birds can't perceive right angles as indicators of obstacles.
True. Right angles, glass, transparent windows - all are architectural obstacles that birds cannot perceive. When birds sees clouds and sky reflected in a glass high rise or trees and shrubs reflecting off your living room window they merely think it's a continuation of the sky or their reflected habitat. Reflected vegetation is the most dangerous, however, birds also try to fly through transparent windows as they try to reach a perch seen on the other side. For more dangerous architectural bird obstacles read this great article by Christine Sheppard on Architecture Week or Bird Friendly Building Design on the American Bird Conservancy site.

images top: Dundarave bungalow -  a 'tunnel' and a window reflecting tall trees and shrubs
center: Staples Residence West Vancouver - a bird death trap. Transparent windows, tunnels and reflective glass
bottom: Cordova St. Vancouver - a combination of architectural eras. Which is the least bird-friendly?