LED lights make moths easy targets for bats

Energy-saving LED street lights are environmentally friendly, but they may not be moth-friendly. When lit by an LED’s glow, the insects are less likely to perform dramatic dives to escape hungry bats, a new study shows.

Researchers at the University of Bristol in England played recordings of bat hunting calls to unsuspecting wild moths. In the dark, 60 percent of moths dove toward the ground to avoid the imaginary predator. But when LEDs lit up the night, only 24 percent of moths attempted this last-ditch evasive maneuver, the team reports August 5 in Royal Society Open Science.

Some moths employ different predator defense strategies during the day than at night, the researchers say. Bright LED lighting may leave moths unprepared for ambushes from nocturnal hunters.