Insects Don't Swarm at LED Lights

28 points | by speckx an hour ago

20 comments

  • Animats 10 minutes ago

    Yes, you need some ultraviolet to attract insects. That's why bug-zappers have near UV lamps. They're usually compact fluorescent bulbs. Some ads say 365nm is the right color.

  • gopalv 25 minutes ago

    My pet theory is that the dimmable LEDs repel insects (when used as a grow light).

    The thing that insects can see and we don't is the rapid flashing of a PWM power controller.

    I wonder if these streetlights have power saving fade-ins as the nightfall approaches instead of clicking on at sunset.

    Like - https://doi.org/10.1109/CSNT51715.2021.9509652

      Velocifyer 16 minutes ago

      Don't forget about flicker free dimmable LEDs. I install them in my house.

      adolph 10 minutes ago

      The article bluntly states: "Moonlight contains ultraviolet (UV) and infrared wavelengths because it is merely reflected sunlight. Insects cue on UV, believing it to be the moon. . . . Incandescent lights transmit UV but LEDs do not. Insects are far less attracted to LED."

      However, my mind developed a similar conjecture to your's: what if the common frequencies of PWM occur within a kinetic visual blindspot of insect vision, like human saccades [0] in the novel Blindsight [1], so that insects are not aware of the LED at all?

      0. https://www.ncbi.nlm.nih.gov/books/NBK10991/

      1. https://www.rifters.com/real/Blindsight.htm#:~:text=%22There...

  • Xcelerate 15 minutes ago

    I wonder if it’s only the UV that makes a difference. I have some Yuji SunWave bulbs (and the NIR versions). Would be interesting to test those at night against normal LED bulbs and incandescent.

  • quirkot 28 minutes ago

    I wonder how much of it is also the LED flicker. If I was a small bug and moving quickly with a high visual refresh rate, I would probably hate the experience of the LED flicker

      worldsavior 23 minutes ago

      There is no such thing as refresh rate for any kind of eye.

        throwaway219450 5 minutes ago

        There are odd visual illusions though, like humans perceive the Wagon-Wheel Effect even though there's no obvious reason it should happen. This is the effect where the speed of a rotating object varies depending on its sync with a discrete exposure period.

        https://en.wikipedia.org/wiki/Wagon-wheel_effect

        https://research.tue.nl/en/publications/subjective-strobosco...

        nine_k 10 minutes ago

        There is for the visual cortex though.

        Try walking outside in a clear night. Look up, notice some stars, or aircraft lights. Now rotate in place, and see how low your vision's FPS is in the dark: the rotation will be visibility jumpy.

        An insect, with its much simpler visual processing, and facing a bright light, will likely achieve a much higher FPS, sufficient for the sub-kilohertz flicker to be very visible.

        jschveibinz 12 minutes ago

        But there is a neurological component in "optical processing" that can be modeled as a discrete rate of update although the underlying physiology is still being investigated.

        quirkot 15 minutes ago

        Yeah, i know that's how the physics works, but effectively my computer monitor doesn't flicker for me but a strobe light does. Whatever the proper term for that is what I'm talking aobut

        smallmancontrov 17 minutes ago

        Nyquist had something to say about that.

        hbn 19 minutes ago

        High perception rate?

        I believe it's known that smaller animals with rapid metabolisms process sensory information faster.

  • okanat 30 minutes ago

    Weird. My home has only LED bulbs. There are still moths and bees who get attracted to the light when I leave the window open.

      hnlmorg 17 minutes ago

      I think it’s to do with the LED flicker. You can sometimes see it in your peripheral vision (ie your light/dark receptors) but your RGB cones aren’t as good at spotting it.

      Insects eyes are biologically very different.

      With LED lighting, if you have lots of spot lights in the ceiling and and open door, you’ll likely find that the light leaving the house is a bath of reflection from different sources inside the house and that likely cancels out the worst of the flicker.

      Brian_K_White 22 minutes ago

      Install a single incandescent somewhere and be less mystified by the claim.

      They didn't say no bug ever goes to any led light.

  • oakwhiz 24 minutes ago

    The study didn't cover high pressure sodium bulbs, the previously popular type in street lamps.

  • ChrisMarshallNY 24 minutes ago

    I have noticed that. We have LED porch lights, and never see the usual moths and whatnot.

  • unpleasurable 22 minutes ago

    Do flames emit UV?

      aaomidi 15 minutes ago

      No but they emit smoke