Why do gnats drown in my tequila and not my soda?

For some reason, I’ve got a sudden infestation of gnats in my apartment. I can live with it - they’ll eventually go away - but for one thing. When I’m sitting and reading with my shot of tequila and my ginger ale chaser, I’m frequently picking dead gnats out of my tequila, and never out of my ginger ale.

Why are they more attracted to liquor than to sugar? I would have expected the other way around.

WAG: Liquor smells like fermentation, meaning the fly thinks there’s rotting going on. Plain sugary smells don’t have that same appeal, I suspect. (Fruit flies and regular flies both seem to prefer rotting things to plain, from what I’ve seen.)

Somwhere in here is a joke about the more effective libation for drowning sorrows. But I’m not sure where it is.

And sorry… no, I don’t know why gnats prefer tequila to ginger ale. I would’ve thought the other way around too.

Pretty much what Ferret Herder said. Fruit flies mostly eat yeast rather than sugar, not to mention that yeast smells much more strongly than sugar does. They don’t care where the smell is coming from, either; if you’ve just drunk a glass of wine and exhale slowly, they’ll be fighting each other to be the first down your throat.

Yeah, it sounds like you have fruit flies rather than proper gnats. They’re attracted to alcohol because alcohol is associated with rotting fruit, and rotting fruit is where they like to lay their eggs.

This, by the way, is why you catch more flies with vinegar than with honey. See also.

Ah, and in that case, I know where they came from.

So if I leave little bowls of tequila all around the place, am I more likely to drown them all, cause a population explosion, or just make a lot of after hours work for the fruit fly police?

Yeah, they’ll have trouble flying in a straight line.

“Sir, I want you to touch your wing-tip to your proboscis.”

That’s why whenever I have fruit fly problems, I buy cheap beer and make a fruit fly trap using the beer instead of fruit. Catches wayyy more. It’s only slightly more messy, and that’s only if you aren’t careful when setting it up or taking it down.

I get the best results with a quarter cup of cheap fruit-flavored vinegar (our grocery has a nasty raspberry one for a couple of bucks a bottle, enough for a year or two) with a few drops of unscented liquid soap in a cruet (we lost its lid years ago). It doesn’t go “bad” – it keeps smelling like raspberry vinegar, not rotten fruit and old beer – so it doesn’t bother me, but the fruit flies think it’s very tasty. They can’t get out of the cruet on their own; no need for the plastic wrap or anything, and when enough flies drown, I can dump the liquid down the drain, run the cruet through the dishwasher, and start over. The cruet lives next to the bowl where we keep bananas out on the counter.

I have not tried baiting the trap with tequila, though. Sounds like the nuclear option.