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Why flying insects gather at artificial light

nature.com

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Re: Why flying insects gather at artificial light

#31

Post by SamBam »

mapreduce wrote: post #29
codetrotter wrote: post #27

So am I understanding correctly that this confirms the common perception they cited: > Insects use the moon as a celestial compass cue to navigate, and mistakenly use artificial light sources instead

I don't think it confirms that. It seems to be one of the popular theories they investigated. Later they say - "In both field and lab conditions, insects rarely head directly towards, but consistently fly orthogonal to the light source. This refutes the fundamental premise of an escape response." "An insect should keep a light source at a fixed visual location for maintaining its heading. Switching light position (Su…

I think you're misunderstanding GP.

This definitely refutes the theory that insects are trying to escape towards the light, because, as the article shows, insects don't head directly for the light, but instead move orthogonal to it.

But this doesn't mean they can't use moonlight to help with flying. The theory, as I understand it, is that they use a distant light source -- e.g. the daytime sky -- to maintain altitude. There's no reason they couldn't use the moon to do this too.

Again, they would not be flying towards the moon, they'd be keeping the brightest light to their dorsal side. Since the moon is distant, unlike a lamp, this would result in steady flight.

I'm not sure that it confirms whether they use the moon or not, but it seems like a possibility.

Re: Why flying insects gather at artificial light

#32

Post by lawlessone »

Simon_ORourke wrote: post #25
micromacrofoot wrote: post #22

Earlier quoted context omitted.

In my experience... kind of. Light isn't the only thing they're attracted to so you'd have to optimize distance and cover different variables for different bugs. One fun thing you can do is relocate small swarms of bugs with a torch to another light source. So if you're being pestered, turn on a torch... and slowly walk the bugs to a different light source (a distant lamp for example). Then turn off the torch and wal…

Would or could that be automated? We are hounded from late spring to the fall by all kinds of flying nasties at our front porch. Some led string that moved them all away would be awesome!

How about a light on a rail? we could race them around a track taking bets.

Re: Why flying insects gather at artificial light

#33

Post by Retr0id »

mapreduce wrote: post #29
codetrotter wrote: post #27

So am I understanding correctly that this confirms the common perception they cited: > Insects use the moon as a celestial compass cue to navigate, and mistakenly use artificial light sources instead

I don't think it confirms that. It seems to be one of the popular theories they investigated. Later they say - "In both field and lab conditions, insects rarely head directly towards, but consistently fly orthogonal to the light source. This refutes the fundamental premise of an escape response." "An insect should keep a light source at a fixed visual location for maintaining its heading. Switching light position (Su…

If your logic is "keep the brightest light source on your left", then for a light source that's nearby (as opposed to "infinitely" far away, like the moon) you'll end up orbiting it.

Depending on your precise navigation logic, you'll either end up with an increasing or decreasing orbit radius. If it decreases, you'll eventually crash into the light source.

Re: Why flying insects gather at artificial light

#34

Post by [deleted] »

beedeebeedee wrote: post #17
alxmng wrote: post #13

Does this explain why bugs seem to swarm at sunset? Because the sun is lower towards the horizon it brings the bugs towards the ground?

Some aquatic insects fly around sunset because the polarization of the light makes it easier to see bodies of water to land on

[deleted]

Re: Why flying insects gather at artificial light

#36

Post by chankstein38 »

nashashmi wrote: post #21

I have a feeling the stars are used by insects to navigate in pitch dark environments. And the lack of stars may be causing a large decline in insect population. Making a road trip in the light polluted northeast america, I was looking for stars in the darkest of forested of environments, and I could not find any stars anywhere. I am not sure if the clouds were there. But I realize I have not seen stars in a long tim…

I'd argue that, based on what this paper is discussing at least, it'd be pretty impossible for them to use stars to navigate. I'm not sure what they'd do in pitch dark environments but if they're using either the sun, moon, or artificial light to help them navigate, I highly doubt stars would even register/be detectable to them.

Re: Why flying insects gather at artificial light

#37

Post by jgilias »

codetrotter wrote: post #27

So am I understanding correctly that this confirms the common perception they cited: > Insects use the moon as a celestial compass cue to navigate, and mistakenly use artificial light sources instead

That’s my understanding too.

The way I thought about this before was that normally an insect would ‘keep the moon’ on one side to navigate straight, but artificial light messes that up and they end up spiraling around those light sources.

Which seems exactly the behavior that they have demonstrated in the research.

Re: Why flying insects gather at artificial light

#38

Post by teeray »

It’s always amusing in the garden center at Home Depot looking at the enormous spider webs (and the fat spiders) around their sodium vapor lamps. It must be that the number of calories required to produce bioluminescence to create this effect must be greater than the calories that could be derived from hunting that way. But if someone else provided that free energy for hunting…

Re: Why flying insects gather at artificial light

#39

Post by paiute »

scotty79 wrote: post #9

I had a really weird observation. Do you know how in the summer flies tend to enter rooms and circle the middle of it (where usually the turned off light fixture is)? And they seemingly can't or don't want to find open window to leave the room? At one point for unrelated reasons I replaced light fixture in my room with more than 200W worth of strongest E27 Philips LED lightbulbs I could find (20*1521lumen). Few flies…

I was under the impression they confuse lights for stars and it messes with them. So if you simulate the sun the probably don’t get confused. You can but red spectrum lights that also are supposed to be bug friendly

Re: Why flying insects gather at artificial light

#40

Post by [deleted] »

scotty79 wrote: post #9

I had a really weird observation. Do you know how in the summer flies tend to enter rooms and circle the middle of it (where usually the turned off light fixture is)? And they seemingly can't or don't want to find open window to leave the room? At one point for unrelated reasons I replaced light fixture in my room with more than 200W worth of strongest E27 Philips LED lightbulbs I could find (20*1521lumen). Few flies…

[deleted]
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