I've been wondering if it would be feasible to place "artificial nests" in the environment (my and my neighbours' yards) to collect nests of difficult-to-notice species. While researching this online, I found a paper where researchers did exactly that.
They were studying cavity-nesting species, so they made small formicaria which contained two separate nests each, by drilling two holes in pieces of wood for the nest cavity, and connecting each to the edge by an entrance hole. (Both cavity and entrance diameter were controlled variables.) They glued coverslips over each hole, top and bottom, to make enclosed cavities, and then sandwiched the entire thing between other pieces of wood (secured with fishing line) to keep them dark and protect the glass.
They got an 18% colonization rate with nests placed in early spring and collected in late summer. However, I would guess that 18% would be closer to an instantaneous occupancy rate (rather than a peak arrived by slow increase during the spring and summer), since ants do move around. If that assumption is correct, I could increase my success rate significantly by collecting nests every two weeks to check for colonization, and then moving the colonized nests into outworlds if they turned out to be species I was interested in (and leaving them be if not).
Does anyone have experience with this method of collection? Also, would it work for ants that require larger nests (by making multi-chamber formicaria)?