Probably using fungus. They are highly sensitive. Molasses and sugars that feed the soil make their carefully maintained reproduction chambers contaminated with an overabundance of fungi and bacteria and they leave. Boric acid is a killer, but you have to plate it in a mix with sugar so as to not poison the soil, but the trace amounts they bring home actually help the soil. Then there are the interesting compounds like Spinosad for example, which is a spray but also is found as a bait.