You say they only target stable flies, while I DO have stable flies, my issues are with cluster flies and black biting flies (I suppose the later would be considered stable flies?) I'm not up to date on my fly species except that they are all annoying... I have been considering fly predators but had these questions, and also of their native/non-native status which has already been addressed here. Will they take care of these flies I've listed or are they useless for that purpose. Also, I have been having an exterminator come early fall every year to spray my house and garages, how long do the fly predators live?
On another subject, any suggestions for horse/deer fly problems? Last year I had issues multiple times where I'd find my gelding soaking wet from running away from a swarm of horse flies, and when I say swarm, I'm talking about hundreds of horse flies attacking him. I had to keep him inside all day with a fly sheet on all summer. Was thinking chickens might congregate near horses legs and nab the horse flies, but I can't get them until next year. Mosquitoes were the least of my problems last year, ugh.