Why are blue-green or white night lights often worse for insects than redder light?

Answer: Because their wavelengths match many insects’ visual sensors

Because those lamps give off more heat than redder lamps — Heat is not the main reason blue-green or white light is often more disruptive. Cool LEDs can still strongly affect insects if their wavelengths match the insects’ visual or timing systems. The problem is the light signal, not simply warmth.

Because their wavelengths match many insects’ visual sensors ✓ — Many insects are especially sensitive to ultraviolet, blue, green, or broad white light, so those wavelengths can strongly affect orientation and biological timing. Redder light often falls outside the most disruptive range for many species. Species differ, but blue-rich lighting is a risky default around insects.

Because they look like the colors of nectar-rich flowers — Flower cues matter for some foraging insects, but streetlight disruption is broader than a fake-flower signal. Night lighting can alter navigation, activity, reproduction, and seasonal clocks. The shared issue is sensory sensitivity to certain wavelengths, not nectar mimicry.