Collisions between birds and aircraft present serious safety and economic risks to aviation worldwide. Research into the potential for lighting to reduce collision risk has been evolving since the mid-twentieth century. Our objective was to explore the potential for using customized light-emitting diodes (LEDs) as a deterrent to wild raptors under natural conditions. The Red-tailed Hawk (Buteo jamaicensis) is among the top 10 bird species struck by aircraft in the United States; these collisions have resulted in aircraft damage, emergency landings, aborted takeoffs, and human injuries and fatalities. We tested the reactions of migrating Red-tailed Hawks to pulsing, high-brightness, monochromatic LEDs that targeted the avian photoreceptors for light of short and extremely short wavelengths. We installed 3 lighting units to illuminate 2 lures at a raptor banding station during the peak of Red-tailed Hawk migration and compared the number of captures and aborted approaches to these lures with captures and aborted approaches at a control station. The proportion of Red-tailed Hawks that aborted their approaches to lures at the treatment station was >5 times that of hawks that aborted approaches at the control site. We observed individuals abruptly changing flight direction as they neared the illuminated lures. Our results suggest that, with further testing and refinement, high-brightness, monochromatic LEDs that specifically target avian photoreceptors could provide a useful tool to divert raptors from hazardous situations.