My experience has been, that you have to sneak up on them. The slighest vibration will cause them to scatter, and they are fast! I've always had luck by just sraying them with the fast attack method, before they get a chance to run.
Is Raid an "on contact" spray? The opening of the mailbox is plenty of motion to cause them to sense danger, and flee.

Now Susan, tell us, were the ants there BEFORE the bottle of wine with lunch, or AFTER?
Bwaaahahaha!
I'm sorry. I just couldn't resist!

Wish I could help you but all I know about ants is Terro works great!

I am no expert, but when they are in the house I just wash the scent trail off and that stops them without poison. Try hosing down you mail box and post. Since you have eggs it may take poison because of the hatching. Be sure and spray in the crevices. They could have a nest at the base of the mail box. I would try flooding the area around the post to see if any come out of the ground.

Maybe they are mind-reading ants, and knew what you had in store for them. Sorry to make light of your dilemma, it sure sounds like a mystery.

Thanks, folks!

Dotmom, it wouldn't surprise me one bit to learn that ants can read minds. I'm laughing, but I'm serious, too! I think there's so much we don't know.

However, I think Foggy's explanation is probably the one that makes sense in this instance. I was hoping not to have to kill them........after all, this is their turf as much as it is mine, and they're not really hurting anything (although the mailman might disagree with that assessment).

Maybe spraying the interior of the mailbox with perfume would discourage them from coming back, you think? I have an old bottle of Chanel No. 5 hanging around.....

I tried posting a link, but it won't let me. It's from the "Cleaning Tips" forum. Go to other forums, choose cleaning tips, then search: ants
I got several answers. Hope this helps.

My best guess is, you disturb the ants, then they grab the eggs and run. When your mailbox is undisturbed for a day or so, they think it's OK to move back in. Then you disturb them again. Cycle repeats.
I have found that rubbing mints leaves across the ant trail confuses their sense of scent so they lose the trail. If you don't want to kill them, perhaps if you wait unti; they're out again and then rub the supports of the mailbox with mint they'll stay out.

I don't like to kill them either. They're so hardworking. As long as they stay outside, I try not to harm any insect.

I understand not wanting biting ants in your mailbox. One way to get rid of them is to sprinkle some Diatomaceous Earth inside the mailbox. It is non-toxic and completely harmless to humans. You will never seen them again. Really. It works.

You can also sprinkle some at the base of the mailbox to keep them from crawling up into the box but DE is ineffective when wet from rain so make sure you use it inside the mailbox too if you are using it at the base of the mailbox.

You could spray Windex on the mailbox pole to keep them from crawling up into the box but they might be going up inside the pole if it is hollow, so this may not work well.

I understand the quick response to use Raid inside the mailbox, but I personally would not want my mail coated with inceticide reside getting on my mail and then my hands. DE is safe and non-toxic.

I have lots of ants in and around my garden and property. I also try to avoid kiling them......I am going to link to a funny article but worth reading and it will explain why I like having them in my garden.. DE doesn't work if it is wet.

Here is a link that might be useful: ants in the garden

Quick Susan - don your Nancy Drew persona and call in Bess and George. This is a job for super sleuths. I can visualize the frontispiece now - a black and white drawing of 3 attractive young ladies huddled around a mysterious rural mailbox peering inside to discover the secret clue that will reveal the cause of the puzzling disappearance.

I like the mint suggestion maybe you could even plant some around the pole.

Maire

Thanks, everyone! Good point about the Raid, Dilly Dally. That's the sort of thing I usually think about, but didn't this time.

Colleen, I have tons of mint! I'll definitely give that a try. Might even dig up some and move it to the base of the mailbox as Maire Cate suggested.

The post is actually two posts placed together. I suspect there's a space between them, and that's where the ants are traveling.

Maire, that's hilarious! I was a big reader of Nancy Drews. I was always surprised how many times she was kbocked unconscious by bad guys but never seemed to have brain damage. Was her roadster red or blue?

Jannie - Oh how I loved Nancy Drew and her books. So much more exciting than the Trixie Beldon or Cherry Ames stories. I'm so thankful my library thought they were worth purchasing. I'm sure that's what encouraged me to become a big reader.

But here's a great little article on all of Nancy's various roadsters, convertible and coupes! Quite interesting.

Here is a link that might be useful: Nancy Drew's cars

Oh, that was fun! I'll have to tell my son-in-law that Nancy would not have been happy with his bright yellow car. :-)

Boric Acid powder is also a sure-fire way of getting rid of ants, fleas, cockroaches and other similar pests.

It works a little differently from DE. Boric acid is similar in that it is a very fine white powder but the way it works is by expanding inside the pest after ingested to the point where the bug explodes. Yow!

When we got a rescue dog years ago it came loaded with fleas. The rescue society, the breeder, our vet and a good friend of mine all told me about boric acid. Flea Busters uses a similar product and charges you lots of money. You can go to Home Depot or similar store and buy a pound of Roach Prufe for under $8 and be rid of all kinds of vermin. And it's safe for pets and small crawling kids. You sprinkle it on your carpet, and any cracks and crevices on your floors and brush it in. We bought a new soft bristle drive-way broom to do the deed and then enjoyed its services outside for many more years.

Anyhow, in the 15 years we owned that flea-bitten, ridden dog, we only had to treat our home twice.

It is just as effective I've read for ants (and of course roaches).

Jodi-

Boric acid is a poison and no, it does not make bugs "explode". LOL.

It is very effective. But you must use caution when using it just like any other product with potential for harm.

Here is what the National Institue for Health says about it and it sounds scary:

http://www.nlm.nih.gov/medlineplus/ency/article/002485.htm

The EPA has very recently downgraded the classification of boric acid from 'highly toxic' to 'moderatly toxic' and require special warnings on packaging. In Europe it is still regarded as highly toxic.

I have used boric acid in my home for fleas but I don't have any children to worry about.

http://www.epa.gov/oppsrrd1/REDs/factsheets/0024fact.pdf

Note both these links are .gov sites and not an amature discussion board.