Keep in mind, Bt infects ALL butterflies and moth caterpillars. I maintain my garden as butterfly sanctuary and plant nectar and larval food plants so Bt is almost last resort in my garden.
Neem can kill off the predatory insects as well as the pests.
It's really hard to get rid of the leafminers once they get an infestation going. I'm having trouble with them for the 2nd winter -- I clip off parts and entire infested leaves. They are easier to spot once they get big enough to see -- I cut them in half inside the leaf -- though I sometimes find a leaf with multiple teeny tiny clear spots and microscopic larvae.
I have some plants positioned several containers deep on the "bench" and the furthest ones are nearly impossible to inspect. Since I have to turn the pots periodically anyway, I try to inspect after each turn and try to get all that I can see from that angle.
I have tried destroying them inside the leaves with most of the leaves intact, but that just gets confusing for spotting later infestations, so I remove any part or whole affected leaves as I find them.
My tools of choice are : pruners, dissection scissors, paper hole punch, bamboo skewer and toothpick.
I encourage spiders among my plants (even indoors) and orb weavers do catch some moths and I think the stalkers get some of the larvae, but pheromone traps might be effective for determining level of infestation?
I was looking up predatory insects for the tomato leafminers, and it seems they are researching Podisus nigrispinus (predatory stinkbugs) for the purpose.
https://onlinelibrary.wiley.com/doi/10.1 ... x/abstract
I couldn't find any source listing in my cursory search so I guess its not an established protocol.
It was intriguing to discover this bit of info because I had managed to introduce pretty bad leaf miner infestation to my summer garden because I was unable to eradicate them from my winter indoor tomatoes last year. ...And this summer I saw one -- a predatory stinkbug. I didn't know what it was and I had one of those rare moments when on seeing an unknown bug I DID NOT catch and ID but actually killed it Felt so bad about it that I remember it clearly -- it looked exactly like the brown Marmorated stinkbugs that are such a garden pest around here, except it had these dangerously pointy shoulders and didn't have the banded legs.
I'm really hoping that wasn't the only one and a new member has joined my Garden Patrol (my name for creatures that hunt and eat the garden pests) . I'm going to go search for more info -- I hope they are indigenous to this area and will be back next season. This summer, the Garden Patrol seemed to keep the leafminers sufficiently in check so that the tomatoes stayed ahead of the infestation.
After some more search, he predatory stinkbug I posted about above was a Brazillian species: https://www.cabi.org/bni/FullTextPDF/200 ... 071083.pdf
The one I saw in my garden was probably our native Spined Soldier Bug....
https://www.stopbmsb.org/stink-bug-basic ... e-insects/
...this link at the bottom of this page was REALLY interesting too even though it's from Ontario...
https://www.biology.ualberta.ca/bsc/ejou ... mmm_24.pdf
Spined Soldier Bugs seem to be readily available:
https://www.google.com/search?q=spined+s ... s+for+sale
Of course in Hawaii the native species is probably different. Is there any research being done by the university there?