I found that you always got a lot of the Ant bait/poison fluid when you bought the rather expensive ant-traps. Also, they were sometimes not really re-usable (very flimsy). I therefore designed these widgets which have a small dimple to take a few drops of the bait.

The lid just pushes on (you may need to sand a little to make sure they come off again) and prevents rain washing the bait away or larger animals getting to it.

I print in ABS but PLA should be fine too (though I would put a dab of varnish on the inner surface in that case if you plan to use them inside the house as PLA can allow fluid to seep through.

I believe you can use a Borax/Sugar solution if you don't have access to the bait fluid.

Thanks, Enjoy!