It was the second night in a row the bridge was closed. The cause, both times, was swarms of mayflies. WATCH: 'Blizzard' of mayflies swarm Route 462 bridge On Saturday night, they caused three ...

SAGAMIHARA, Kanagawa Prefecture--A motorcyclist was injured in an unusual wipeout caused by a massive swarm of mayflies on a local road on Sept. 13. Tens of thousands of mayflies congregated over ...