They are shipped in the pupal (cocoon) stage which are the little black things. Normally they’ll start emerging within 2-7 days after arrival in summer, (later when cooler) but it’s OK if they’re emerging on delivery. They look like tiny little ants with wings. Like this When its cool, keeping them in a warmer area (80-85°F) will speed up their emergence. When it’s hot keep them under 100°F and out of direct sunlight while in the bag.
Holding them longer than 5 days after that may reduce their effectiveness. Sometimes they are quite stinky, but that does not indicate a problem. Call if none have emerged on the 7th day after delivery in summer (14th day when high temps are 72°F or less). We guarantee live delivery and will replace if necessary.
Sprinkle them out near all areas where there is, or was, fresh manure (or other rotting organic matter) that remains moist. This is where flies reproduce and Fly Predators find and kill them at the pupal stage. Fly Predators themselves do not need or eat moist manure, so don’t leave some behind for them. It’s best to remove all manure or spread it to get it dry within 5 days.
Put some near the manure corner of corrals, the pasture rough areas, the manure pile as well as arenas and dry lots. Put them along fence lines or places where they won’t get stepped on. For the barn leave 5-10% in the bag and hang it in breezeway.
Fly Predators can travel up to 150 feet, but it’s better to get them within 50 feet of fly breeding areas. Flies can’t reproduce in dried manure or feed, so don’t put Fly Predators there. Even if you muck out daily, put some where manure was if the spot is kept moist from urine. Flies reproduce in rotting vegetation as well as manure. Put Fly Predators near any spoiled hay, feed, round bale feeders, grass clippings, etc.
Try to dry up moist areas such as near water troughs, leaky faucets, under stall mats, etc. Wetter than normal weather usually produces more flies. In that case add more Fly Predators to keep control.
All of which will eat the pupae that Fly Predators are in at arrival. If you have free range chickens or ants put the Fly Predators in open sacks hung off the ground. Hiding them in grass can help with birds.
They are much more sensitive to pesticides than pest files. If you have to spray a horse do it away from any fly breeding area; i.e. not in the stall. If you use a residual spray apply it only to pest fly resting areas (a sunny wall, ceiling rafters) avoiding pest fly reproduction areas (manure, rotting vegetation). Fly Predators will only be found in the reproduction areas.
It takes about 30 days from first release to see a difference if you start after the pest flies populations have built up. If the fly pressure is great, use double or triple the normal Fly Predator quantity for the first few months to catch up and aggressively reduce adult flies as quickly as possible. For every adult fly you see, half of them will be females who can lay 900 eggs during their 21 day lifetime. Stopping this reproduction quickly helps your Fly Predators gain back control.
These will not harm Fly Predators. Pick the right trap for the kind of flies that are bugging you. Most traps are for House Flies. If you have biting Stable Flies (found typically on legs and cause stomping) get a biting fly trap. Put attractant traps (usually water filled) away from your house or barn as these draw flies from a wide area. Sticky traps don’t draw from a wider area and are OK in barns, but need to be in bright areas. Wide area spraying is often counter productive as it will decimate the Fly Predators and other beneficials so the pest flies will build up even faster without any natural control.
so if neighbors have animals suggest they use Fly Predators too or put some of yours there.
The less manure there is on the property, the less flies you’ll have. Do the best you can to remove it, dry it or concentrate it into one area. If you see a reduction in flies, but still have too many, try 50-100% more Fly Predators for a month or two.
Flies are in our living room and one bathroom. We cleaned with bleach but they still swarm in those two rooms. Can we use fly predators inside the house?
I have been using fly predators for a couple years now. My fly problem is still bad. I have grass in my back yard along with rocks, and other plants and a veg/herb garden. I can see the flies flying around on the grass and rocks. I am a dog sitter and have max 5 dogs at a time. I pick up dog poop every day. I have fly traps from Home Depot. Please help. I do not enjoy my yard anymore.
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