My name is Hadar and I live in Israel. I am the owner of the company for pest control in Israel that specializes in the extermination of ants using baits
During the last five years we are dealing with the failure of eradication of the species Plagiolepis. We've tried most types of bait offered the U.S. pesticide market without success. Needless to say that spraying pesticides is not effective at all.
We tried various baits containing borax or fipronil or abamectin B1 imidiachloropid.
The baits contain honey dew or protein. Often appears in the attraction of that work and "workers" vigorously and after a while sometimes minutes, sometimes days after the placement of abandoned ant bait
Can I get some information about the lifestyles of this ant? Such as:
What kind of diet prefers this species?
Is there more than one queen in the nest?
How to deal with this pest
This species is very common throughout the country from north to south
Unfortunately, an Israeli research on this species is not done yet
Sorry to hear that you're having trouble with Plagiolepis. Although only a few species have been studied in depth, it seems that there is evidence of polygyny (multiple queens in the same colony) in every species in which this quality has been looked for ( P. pygmaea, P. xene, P. taurica, P. schmitzii, and P. maura - data and references in Thurin et al. 2011; DOI: 10.1111/j.1365-294X.2011.05161.x).
As for what your Plagiolepis eats in the wild, it is likely that even if we did know what species you were working with, there would not be a complete, published study that would answer this question. What is more important is that you continue to experiment with baits to which this ant might be attracted that you can mix with the appropriate poisons. Invasive ant expert Cas Vanderwoude (https://www.littlefireants.com) explains:
We have Plagiolepis alluaudi here in Hawai`i. They seem fairly "skittish" and do not seem to feed on any particular food source. I think they are present in homes more for water than anything else.
My standard approach would be to offer a buffet of food items that they might feed on, add a toxicant to the most attractive item and bait with that mixture. So Hadar, try a little (1)peanut butter, (2) jam or jelly, and (3) spam or tuna or fish flavored cat food. Also, try water. Put it in a vial filled with cotton wadding so the ants can "suck" the water from the wadding. You might be surprised - it might be water they recruit to most! If that's the case, thank my friend Evan Harris for that suggestion... if water and sugar are both attractive, you can make a nice attractant out of sugar water (25% sugar) and place it in the vials mentioned previously.
Adding a toxicant is the next step. If you have fipronil it will be the most effective. The most important thing is the dose. DO NOT OVER-DOSE!!! For fipronil, use only 0.1g/kg bait mix - NO MORE! The effective range will be 0.01-0.1 g/kg active ingredient. Any more and it will take effect too soon and leave the queen(s) unaffected. Repeat baiting every 6-8 weeks."
In addition to Cas's tips, I would add that it is important to apply poison at an effective spatial scale. If you're going to poison the ants in one person's house, but they live two meters away from a large colony, there is a very strong likelihood of re-infestation. Cas's point about re-applying baits is also very important; no treatment will kill 100% the first time. Often, treatments will kill around 90% of the ants at most, so it is important to keep re-applying the pesticide at the right time intervals. Ants do not eat while they are in their pupal stage (something like the cocoon a caterpillar makes before becoming a butterfly), so re-applying pesticides while the same ants are in their pupal stages will not increase the effectiveness of the treatment.
For further information about dealing with invasive ants, I'd encourage you to check out Cas's website (above). For example, there is some information on treating potted plants for pests by submerging them in water at 45C which might be useful for some situations.
I hope this helps!
Jesse Czekanski-Moir, Cas Vanderwoude, and the AntAsk Team