Best biting fly traps?

My horses are over run with biting flies. They are getting bitten in the sheath area/bellies. They are not the HUGE horse flies but black, sleek/thinner looking flies. Swat on the underside helps but I am now considering an Epps or other biting fly trap. Do any really work?? I already use fly predators. They are biting like it’s August and it’s only May!

I love my Horse Pal traps.
You can move them around if you’re not catching much in one area.
The biting flies you trap become dried out husks, so no stink when you empty it.
Right now I’m trapping deer flies and those awful crotch biters.

Biting flies are untouched by fly predators because the biters breed in a different environment.

We get a few green heads and the odd black “cruise missile” horsefly. We tried a horse pal trap and got little with it. I’ve been other places where they are non-stop. Biting flies are simply a stage of hell in some places.