Crows of Chang'an Ave

Scientists and folklore try to explain the mysterious 'murders' along ancient street

Most evenings as the sun sinks over the horizon on Chang'an Avenue, a cacophony of "caws" can be heard echoing along the central Beijing shopping street as thousands of crows gather.

Wary shoppers along the historic avenue hurry along paths pasted with white droppings, spurred on by both the cold weather and the eerie congregation overhead.