Mayfly “Snow”
Millions of mayflies gathered over the medieval bridge give the impression of a summertime blizzard.
See Swarms of Bugs Descend Like a Summer Snowstorm
Each summer, millions of mayflies rise from the Ebro River, converging on the medieval stone bridge of Tudela, in northeastern Spain.
Each summer, millions of mayflies rise from the Ebro River, converging on the medieval stone bridge of Tudela, in northeastern Spain.
Attracted by lamplights along the bridge, the insects swarm the area in a fluttering cloud of white wings. (See amazing swarm pictures from National Geographic magazine.)
After spending up to a year underwater as larvae, these fragile insects emerge from the water to mate, lays eggs on an aquatic surface, and die—all in the span of a few hours.
Many of the mayflies that gather above the Ebro River end up laying their eggs on asphalt instead of the water—which mirrors the river’s surface because of the light. So most of the eggs never end up hatching. (Also see
