Glass architecture is killing millions of migratory birds

"Most casualties are small—sparrows, starlings, warblers, and wood thrushes (which happens to be Washington’s official bird). Twice a year during spring and autumn, millions of birds travel thousands of miles, tracing ancient routes or flyways in search of fertile feeding and nesting grounds."

"Frequently, birds are lured by artificial lights or become disoriented by smooth, transparent surfaces and slam right into the glass. Most die on impact; those that are maimed often fade overnight before the Lights Out crew can come to their rescue."
 
http://qz.com/372493/lights-out/