What could be killing all these ants?

[Megan73]

Freaking a bit - I just noticed today that a spot outside our front door was littered with hundreds of large, dead and dying black ants. I swept them up this afternoon and there are dozens more there now. Some appear confused - for an ant, anyway, walking in circles and "wrestling" each other (or maybe carrying away the dead, which I've seen ants do)?
WHAT is going on? I haven't used pesticides beyond Borax.

[InchByInch]

Borax is often used as an ant killer. Perhaps it was that?

[Megan73]

Thanks but I doubt it - we used Borax traps inside without apparent effect. And aren't the ants supposed to take the borax back to the colony and die there?

[Three~Little~Birds]

Weird.
I don't have the answer, but I am noticing 'slow' and dead ants around my house, too. I am currently using some traps, too. Some of the ants (big black kind) are wandering around, very slowly, seemingly confused, too. It is more like a dozen, though, not hundreds!!
Freaky!

[TexasG]

Not sure, but did they have wings? I know that we had swarmers before and they come out and die very quickly. Termites are the same way--wings too.

[Megan73]

Originally Posted by Three~Little~Birds

Weird.
I don't have the answer, but I am noticing 'slow' and dead ants around my house, too. I am currently using some traps, too. Some of the ants (big black kind) are wandering around, very slowly, seemingly confused, too. It is more like a dozen, though, not hundreds!!
Freaky!

It IS FREAKY and of course my fear is that there's some toxin killing them that could hurt us, too. But I feel better that it's happening to you, too. I probably exaggerated when I said hundreds

Originally Posted by TexasG

Not sure, but did they have wings? I know that we had swarmers before and they come out and die very quickly. Termites are the same way--wings too.

They're not winged. In my Googling I discovered that the winged ants can have "mating swarms" where you see a ton of them.

[deditus]

We had small ants coming in our house this spring and going to a hunk of something - either wood filler or floor wax - in our floor where there is a piece of wood missing, apparently eating it and dying. There were scads of them then coming in to pick up their dead. Strange, but perhaps they are eating something poisonous to them but not necessarily harmful to you.

[bigteamug]

Ants can go all over foraging - is it possible that one of your neighbors sprayed for ants? I would find a cheap/old (disposable) broom to sweep them up and get rid of any you see before the kids get into them. Toss the broom, too, when the issue is gone.

They might be carpenter ants.