Why Are Bugs Attracted to Light?

Termite Queen Flying At The Bright Lights.

We’ve all been a little disgusted when looking at a porch light and seeing the collection of dead bugs in the glass. Why does this happen? Specific bugs, primarily flying ones, like to head towards light sources. There are a few theories on why bugs are attracted to light, and we’re breaking them down below!

Phototaxis, the Phenomenon of Being Drawn to Light

Many organisms operate under phototaxis, which is the phenomenon of being drawn to light. Something can be either negatively or positively phototactic. Bugs drawn to light are phototactic (they go towards the light). These include flies, moths, mosquitoes, and more; most flying bugs are drawn towards light. Ground-based bugs are often negatively phototactic, which means they run away from any brightness. These include cockroaches, ants, and scorpions.

What Is It About Light That Draws Bugs?

There’s a scientific debate regarding what exactly causes bugs to go towards light sources. We haven’t been able to nail down a specific reason they have this behavior that encompasses all different bugs. A few of the current theories include:

1. Clear Path

We can’t see the sun on a rainy day because of the clouds. Many scientists theorize bugs head towards light because there’s a clear path. The thought process is: if a bug can see the light, nothing is blocking it, and they’re able to fly without worrying about hitting anything.

Two light bulbs that will attract bugs

2. Light Is the Bugs’ Compass

Our ancestors used to use the sun’s rising and setting locations as a way of telling direction. Bugs do the same thing! Based on where the light is, they know which way they’re going. The theory for this one is that bugs will be drawn towards any light source, confusing it for a natural directional sign.

3. Light Gives Off Heat

Even modern LED bulbs give off a small amount of heat. The heat from an artificial light source can be attractive on cooler nights, leading scientists to believe bugs that it’ll warm them up.

4. They’re Blinded

Ever had someone turned on the light unexpectedly while you’re trying to sleep? You can’t immediately focus on anything because you’re temporarily blinded. A few scientists think this is why bugs are attracted to light. The theory says artificial lights are so bright that bugs are overwhelmed by them and lose their sense of direction.

Which Lights Attract the Most Bugs?

Regardless of the reason, many flying bugs are positively phototactic and like to head towards your home’s lights. We can guess you don’t want this, so now the question is: what kind of lights attract the most bugs? Bit of bad news here: LED lights are the most popular lights to bugs. The cost-saving light bulbs so prevalent in American homes nowadays emit UV light that isn’t visible to humans (but is very attractive to bugs). Brighter lights are the most popular. We recommend you don’t stop using low-cost LED bulbs but instead contact a professional pest expert at Dr. Death Pest Control to mitigate the bug’s presence. We can help keep your lights safe from bugs! For more common pest and other related pest tips, please contact Dr. Death Pest Control.

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