Quick Fly Control Instructions
Wait! Don’t release your Fly Predators until you see a dozen moving around.
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.
After emergence starts, release them in the next day or twoas 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.
Release your Fly Predators where pest flies are reproducing. This is often not where you see the adult flies.
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 Fly Predators out proportionally to how much manure or rotting organic matter is in each area.
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.
Watch Out for ants, birds and chickens 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.
Keep pesticide sprays away from Fly Predators
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.
Fly Predators stop pest fly reproduction but do not affect existing adult flies.
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.
To get adult flies you can use traps, sticky paper or bait as 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.
Flies travel 1/4 mile or more so if neighbors have animals suggest they use Fly Predators too or put some of yours there.
Good manure management makes a huge difference. 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.
Tips For Dairy and Beef Operations
Controlling pest flies effectively with little or no pesticides on large livestock facilities is absolutely possible.
However it helps enormously if you know what kinds of pest flies you have, where they are coming from, their life cycle and dependencies,
to gain ongoing control with the least amount of work and expense. You don’t need to be a “fly geek” to have good results, but a little bit of knowledge goes a long way.
So please take the time to read this information. Your animals (and spouse) will thank you for it.
It sounds simple but overall sanitation is the most important and effective way to control flies. The smart thing is to clean up the 10% of the farm
that’s probably making 90% of your flies and let Fly Predators take care of the rest. You’ll spend less and get better results.
Identify the Fly. The first step is to identify the insect(s) that are plaguing you and your animals.
This is important as the variety of flies that bother your animals can come from dramatically different sources and knowing where to attack the
problem is essential. For example, House Flies primarily reproduce in moist (not too wet and not too dry) manure, but Biting Stable Flies prefer
rotting vegetation (spoiled feed and silage) over cow manure and Horn Flies and Face Flies reproduce only in pastured cattle manure that is
undisturbed. Most of the common dairy pest flies are easy to identify by simply looking at your animals. If the flies are primarily on the legs or
flanks, causing the cows to bunch and stomp, those are Stable Flies. If they are small and primarily on the back, those are Horn Flies.
House Flies can be anywhere but they will be the large ones on the face around the eyes and muzzle.
Find the Maggots. The second thing to do is look for larvae (maggots) as this will tell you where your fly breeding “Hot Spots” are.
You’ll find larvae in moist manure areas or the wet edges of a silage pile or bunker, or the bottom of a round bale feeder, the spilled material
outside a feed bunk or under a conveyer. Scratch below the surface to find them as they’ll never be on top. See a maggot or two, no big deal just
make sure there are some Fly Predators near here. But if you see lots of maggots, this is a prime hot spot to clean up quick and put more Fly
Predators near here. To control Horn Flies you will need to put Fly Predators in the pastures every 150ft.
Manage Your Manure. For most commercial livestock operations manure management is THE most important variable in any House Fly control
program simply because this is the largest single source of (from a fly’s perspective) “the good stuff”. There are two variables with manure that
you can most easily change. The first is the quantity of manure, the second is the moisture content of that manure.
Move It. Hauling manure at least a 1/4 mile away in the summer no less often than every seven days is one option.
This distance and time is important as flies generally travel no more than 1/4 mile (they can go farther) and they take at least 8 days to go from
an egg to an adult fly at summertime temperatures (85°F). So rather than cleaning out the barn and piling it right next to it
(which insures that ALL the flies coming off that manure will make it to your barn) stockpile it near where you will be spreading it far away.
Sink It. A fly larvae has to be in a medium that is between 40-60% moisture or it simply won’t complete its development.
Increase the moisture of your manure by holding it in a liquid lagoon as a fly can’t reproduce underwater. But make sure that you do not let a
solid crust form on that lagoon or you will have a huge fly factory there. The top of the cap will be too dry and the bottom next to the water
will be too wet, but somewhere in the middle will be just the perfect moisture for optimum fly production. The cost of diesel or electricity to
agitate it regularly, or adding bacteria to help keep it liquid, or installing a solids separator can be great investments in fly control.
Pile It and Compost It. In areas that receive regular summer rains collect the manure frequently and stockpile it in a pile.
When you do this the manure that is deeper than six inches from the surface becomes too hot for a fly larvae to survive due to decomposition.
So even if the pile is mountainous only the outer surface will reproduce flies. If you are not turning it, one big pile is better than a bunch of
small piles as you are trying to minimize the surface area. A compost barn that is roto-tilled daily produces very few flies. Likewise composting in
rows and turning frequently is very effective for creating great fertilizer and few to no flies.
Dry It. For areas that receive little moisture during the summer a good choice is to dry the manure. Best is daily collection and spreading
manure thinly on crop areas or a concrete pad. Running a harrow or screen drag around your pens and pastures to break up the pats into smaller
faster drying pieces can be very effective. Keep in mind that you are in a race with the flies as you want that manure to be less than 40% moisture
by the 5th day from new. This is because at the optimum temperature of approximately 85°F it takes at least 5 days for a pest fly to pupate
(form its cocoon) which is a really critical time for the moisture level. If it’s drier than 40%, the fly’s puparium (cocoon) doesn’t form properly
and that particular fly is toast.
Clean It. Do the best you can to clean stalls, corrals, paddocks, pens, drainage areas, loafing sheds, calf barns and hutches, feeding aprons,
spilled feed and other decaying organic matter at no more than a seven day interval. If you remove the pupae before the flies have emerged, (8 days minimum)
the difference can be enormous.
Don’t Overlook Spoiled Feed. The Biting Stable Fly prefers rotting vegetation, not cow manure. So if you have these bad boys bothering your
cows look for maggots in the wet spoilage at the outer base of a silage pile or on the front edge of the bunker, in a bedded pack barn by the fence,
in calf hutches and pens bedded with straw, spoiled feed in front of or behind a feed bunk, the old feed at the bottom of round bale rings or the bottom
of square bales. The best way to fix this is to spread out that spoiled feed and dry it. If you can, bed your calves.
Detailed Fly Control Instructions
Factors To Consider Before The First Release
Existing Fly Problem Fly Predators attack the fly’s pupa (cocoon) stages only.
They do not attack the adult pest flies. Thus, the adult flies currently existing
must either be removed by supplemental methods or tolerated until they live out
their short life span of about 21 days.
Remember, it is always better to start your releases of Fly Predators early in the fly
season and prevent a buildup of flies, than to have to remove the adult flies after they
have attained intolerable levels. Although the quantity of Fly Predators recommended are
generally suited for most situations, occasionally larger quantities are needed for severe
fly problem areas.
At the height of the fly breeding season you may need an extra shipment or two so that the
Fly Predator population can keep up with the pest flies which reproduce up to 9 times faster.
(That’s why we provide Bonus shipments). The female Fly Predator lays about 75 eggs with 14
to 20 days to emergence while each pest fly female can lay 500 eggs with as few as 8 days to
emergence. It is due to this large reproduction capacity of the pest fly that the Fly
Predators are not self-sustaining to a degree high enough to maintain full fly control and
thus need to be supplemented each month of the fly season. Some of the Fly Predators will
overwinter just as the pest fly does in the cocoon stage and each year they will become better
established, thus control improves with time.
Ants If you have many ants in the area where you are going to put the Fly Predators,
it is best to eliminate them first, as they will eat the Fly Predators.
Birds Fly Predators inside the pest fly pupa are very appealing to birds. If birds
or chickens are eating the Fly Predators before they emerge from the fly pupa, do not
spread the Fly Predators in the manure but leave them in the opened pouch hung above
chicken level on a nail or thumb tack. This way they will fly to the manure as soon as
they emerge. In about a week or 10 days pour the remaining contents out. Another method
of protecting your Fly Predators until they emerge is to cover the fly pupa lightly
with leaves, dry manure or dirt.
Insecticides Unlike pest flies which can often be only slightly affected by insecticides,
Fly Predators are very susceptible to these. Thus, if sprays are currently being used and
the over spray will fall on a large part of the manure inhabiting Fly Predators, the sprays
should be discontinued.
Generally, feeding internal larvicides to your animals will not adversely effect the
Fly Predators. Occasionally manure will have enough poison residue left in it from past
heavy spraying to completely kill your beneficial insects. The only solution here is to
clean out and start over again.
Storage Procedures For Fly Predators
If you need to store your Fly Predators before releasing them, simply keep them in their
pouch which is sealed, but breathable. They will keep this way for 3 days after they
start emerging without any adverse effects. If absolutly necessary to hold for a
longer period of time put the pouch containing the Fly Predators in the refrigerator
as soon as it arrives. Their productivity slowly decreases if kept longer than
about 5-7 days. Do not allow them to freeze.
Integrated control
Integrated control is the augmenting of biological control with other methods which
gives the highest degree of fly control that will not harm your beneficial insects.
Several of these methods that have been used successfully with Fly Predators are
traps, sugar based fly baits, fly papers, electric and black light fly traps, and
spraying non-manure areas where flies congregate, such as rafters in the evenings,
fence rails and barn sides in the morning sunshine, shady places in the heat of
the day, etc.
Sometimes the degree of fly control achieved is not as high as desired due to flies
migrating in from neighboring breeding areas. Pest flies are hardy fliers and easily
migrate up to a quarter mile a day, sometimes up to one half mile. We often see people
who are very conscientious about fly control on their property but are surrounded by
neighbors who do little or almost nothing on those lines. In these cases a high degree
of fly control is almost impossible to achieve (regardless of the methods used) unless
the neighbors also participate. We will gladly supply fly control information to
your neighbors if desired.
Manure Management Tips
The most ideal manure management program is to clean frequently and spread the manure
thinly on fields where it will dry quickly. The pest flies larvae are highly susceptible
to this drying and will not pupate (form their cocoon) properly unless the medium they’re
in is moist. If frequent cleaning is not practical and the manure accumulates to more
than 2 or 3 inches deep, it should be stacked in a large pile. This will reduce the
surface area and the heat generated in the core of the pile will force the pest fly larvae
to the outside 6 or so inches.
Fly Predators live their entire life on or near manure and are partially transported
wherever it goes. Cleaning will disturb the adult Fly Predators and they will fly off
and migrate to new manure deposits. You may lose someof the next generation of Fly
Predators that have not yet emerged from the fly pupa, but they will travel along to
wherever the manure is taken and give control to that area. Often it is best not to
clean down to the ground, but leave an inch or two of manure, this will also help your
natural population of beetles and mites which also help control pest flies.
One important fly-breeding site that is often overlooked is moist decaying vegetable matter.
Rotting hay and straw spilled behind feeders and even lawn clippings offer an excellent
breeding site for pest flies. This vegetable matter should either be removed or spread
out so that it will dry.
Another fly-breeding site that is often a problem is where livestock urinate on their manure,
keeping it moist. If removal is not practical then sprinkle with hydrated lime (available
from farm supply houses). This prevents flies from breeding and helps the odor. In fact,
it is a good practice to put lime on all sites where your livestock urinate, but do not put
it on manure where Fly Predators will be.
How To Recognize The Fly Predators And How Long Until They Are Established
When you see the emerged Fly Predators in their shipping pouch that is their full
adult size. When the Fly Predators have emerged, the fly puparium, in which they are
shipped, will still be intact, but with a little hole in it about 1/32” in diamater.
One can inspect for the escape holes in the pest fly pupal case to determine if the
Fly Predators have emerged.
When Fly Predators become established you will be able to see the tiny Fly Predators
on moist manure piles. Although there are many small gnat like insects commonly found
on the manure, the body shape, color and behavior of Fly Predators allows an experienced
eye to detect them. One common misconception is that the smaller flies found around manure
are “baby flies”. They are not baby flies, but different species of pest flies.
Like butterflies, Fly Predators and pest flies develop through a complete metamorphosis,
from the egg, to the larval stage, and then emerging from the pupal or cocoon stage as
full sized winged adults, remaining that same size for life. The pest fly’s egg and larval
(maggot) stage are spent in the manure, but just before entering into the pupal stage the
larva crawls up to 10 feet away from the manure and digs itself into the soil if possible
to undergo its metamorphosis. It is the pest fly’s pupal stage that the Fly Predators attack.
The female Fly Predator digs down and lays one or more of her eggs in the buried pest fly
pupa. The female Fly Predator’s egg quickly hatches into a larva and starts feeding on the
immature pest fly pupa. Then it undergoes its metamorphosis from pupal stage into full size
adult. All of this takes place within the pest fly pupal case and the Fly Predator emerges
to start the cycle over again. The time it takes to establish biological control is often
longer than expected, but it is well worth the wait. It is not unheard of for biological
control to take a season to become fully effective, but once Fly Predators are established,
pest flies will never build up to nuisance levels.
Live Delivery Guaranteed
Your Fly Predators should emerge within 3-10 days after delivery if they are maintained at
approximately 80ºF. Often their emergence will be delayed as their development time is very
temperature dependent and they are often kept at temperatures lower than 80ºF during shipping.
If at 14 days past the arrival date they still have not emerged we will gladly send you
another shipment. Please call customer service at 1-888-562-4241.
Due to the minute size of Fly Predators, we measure their numbers by the volume of the pupa
cases they are delivered in. Since one to seven Fly Predators will emerge from each pupa case,
depending upon the species, the volume of your shipment may vary from time to time, although
the number of Fly Predators enclosed will be the same. Normally we enclose more Fly Predators
than ordered to insure live delivery of the quantity requested.
Copyright Spalding Laboratories, Inc. 2010 FLY PREDATORS is a trademark of Spalding Labs