Why do fire ants often build their mounds close to the sidewalk?

[raccoon]

Is it because it's warmer?

[GodlessBiker]

1. How else do you expect them to walk to the grocery store?

[IndianaGreen]

16. LMAO! n/t

:rofl:

[Captain Hilts]

2. Protected from rain?

[Lerkfish]

6. actually, I think its the opposite

the edges of a sidewalk provide rain runoff. ants need moisture.

[Marksbrother]

3. Yes, I think so.

Either that, or it's a tactically superior location offering quicker access to enemy ankles and heels.

[Buzz Clik]

4. I've wondered the same thing about turtles and highways.

Why do turtles insist on crossing the highway? Miles of open country where they came from, and they just can't fight the urge to be crushed by a truck.

Why do squirrels run under my wheel? Why do bugs think they can land on my windshield when I traveling over 50 mph?

Don't get me started about moles ... but why do those little bastards absolutely have to burrow in my lawn?

[Tuesday Afternoon]

5. Why do birds suddenly appear every time you are near?

[Lerkfish]

7. just like me... they long to be....

[FiveGoodMen]

11. ... within bombing distance when nature calls

[cpompilo]

8. Fire ants also build their nests on the south sides of trees.

I'm guessing that's for warmth.

[panzerfaust]

9. It is because of the cell-phone towers?

If you notice, they also build next to flat rocks, and the tops of fire-ant nests - even those that are mounds in fields - are crusty and hard so it might have something to do with protection?

Fire ant nests are complex burrows going down up to 3 feet, and they have widespread foraging tunnels leading out - over 50 feet - from the mound. My thought is that sidewalks tend to have moisture, provide a protective cover for part of the nest, and are often right next to a good food source.

The good thing about fire ants is that they seem to have killed off all the ticks, and many rattlesnakes; the bad is that they are very aggressive, really do sting, and also like to make nests in outdoor electrical boxes. The worst is that they have also killed off all the red ants and horny-toads (not a toad, but a very attractive, small, harmless and easily caught lizard - ones which many a child delighted in spending hours watching horny-toads eat ants).

[zipplewrath]

10. Do they?

It may be due to the brief nature of your question, but there are multiple variations of that question that could illuminate several different possible answers.

1) Do Fire ants MORE OFTEN build their mounds close to sidewalks?

2) Why do we often build sidewalks in places fire ants tend to build their nests.

3) Is temperature a consideration in where fire ants build their nests.

4) When we build sidewalks, do we alter the geography such that it attracts fire ants?


Technically, in logic circles, your question indulges in the "logical fallacy" of "begging the question". I.e. it presumes something to be true, which has yet to be established. "Do you still beat your wife?". In the courtroom dramas, you'll see the objection "the question presumes facts not in evidence". In scientific circles you'd be expected to frame your question in this manner.

"Is there any relationship between where fire ants build their nests, and where we build sidewalks?" Only after addressing that fundamental question, would any peer reviewed paper be allowed to even discuss possible hypotheses about causes for the relationship.


Oh, but to answer your question, they probably don't. You probably just tend to notice them more when they are.

[panzerfaust]

12. True, in a sense

In absolute numbers MOST fire ant nests are (in the USA), I am sure, mounds in the middle of fields, and are NOT found along sidewalks.

However, in US yards, most (based on a recent study ( N=1, vide infra)) are, in fact, found along side walks. Though they also favor sites adjacent to, or under flat rocks (they do not seem to like to be next boulders as much - but then, boulders are more rare than flat rocks in most yards, so I will not argue this point), or inside any outside electrical connection box - even if it is NOT on the ground.

A quick survey of my yard: 8 along sidewalk, 3 next to flat rocks bordering garden, two mounds in lawn.

Oh, and the sidewalks here in the South were not built where "fire ants tend to build their nests" since the "fire ant" in question is NOT a native fire ant, but a species (Solenopsis invicta{1}) introduced to the US in the early part of the last century from South America, and so would be expected to build nests somewhere in South America, and not in our yards at all.

In short, far from being riddled with "logical fallacy", the observation made, and question posed, by the OP is one often on the minds of those who live in RIFA{2} country. Especially when actively standing in such a nest ... when one only meant to go out and look at the stars.

The common name for these ants is one of the most accurately descriptive names ever given to a creature {3}: "fire ant" being the name in most countries where they occur, and "wash foot ant" (formiga lava-pé, as well as the usual formiga de fogo (fire ant)) in Portuguese; the one name referring to what it feels like to be standing in a nest, and the other to the only way to really get them off!

Notes:
{1} Aka Solenopsis wagneri to pedants
{2} RIFA: Red Introduced Fire Ant
{3} Personal communication from God

[zipplewrath]

13. Higher correlation

"A quick survey of my yard: 8 along sidewalk, 3 next to flat rocks bordering garden, two mounds in lawn ."

I'm seeing a pattern here of very high correlation. I only mention this because along my sidewalk here in RIFA, I have zero mounds near my sidewalk, but then again of the 85 feet, only 5 feet has any lawn. Get rid of the "lawn". It's as foreign as the fire ants.

[panzerfaust]

14. we are trying to do so, have mostly xeroscape

... and actually most would not consider ours a "lawn" at all, as it is Bermuda Grass {1} (no, we have no neighbors who would come lynch us).

Notes:
{1} Cynodon dactylon, which, of course is not native to either Berumda or N. America. But, come to think of it, neither are humans.

[panzerfaust]

15. Actual Answer. One advantage to being at a university ...

... is that when your email ends in ".edu" other academics are likely to write back to you.

So, I wrote a fire-ant expert about this question (fire-ants next to rocks and sidewalks). Gave my opinion of why (moisture, protection, close to food). Also asked about what to me seems a clear correlation between the disappearance of ticks, horny toads, and near disappearance of rattle-snakes (in parts of Texas), with the in-migration of the RIFAs and wondered if these events were causally related.

Here, in part, is his reply:

You are correct about moisture and protection...thermal buffering is probably a factor also.

There is little doubt that many arthropods, including ticks, are knocked back by fire ants. Horned lizards and other egg-laying herps probably lose eggs to fire ants and certainly the latter lose favored food (harvester ants, termites) to fire ants. Rattle snakes do better than other snakes because they bear live young but their food (rodents) are reduced by fire ants.

So, I think it safe to say that RIFAs do prefer (because of moisture, protection, and thermal buffering) to live next to rocks and sidewalks - instead of in the open.

[joshcryer]

17. That's very cool. You guys' discussion is fascinating.

Now why do the buggers evacuate their nest at times and have practically their whole population scattered across the sidewalk.