Fly Exterminators - Fly Control




Scientific Names: Muscidifurax raptorellus, Muscidifurax zaraptor, & Spalangia cameroni

Our Fly Exterminators are a predator to 95% of flies, including house flies, lesser houseflies, horse flies, filth flies, bot flies, biting stable flies, and various other fly species.

Less complete on the false stable fly, face fly, flesh fly, and horn fly since these species complete their life cycle widely dispersed in pasture.


Knowing what's bugging your animals is the first step to solving the problem.





A natural way to control flies that is people, pet, and planet safe!  

Protect your pets from fly-borne diseases with our Fly Exterminators.
Delivered in the parasitized pupae stage and ready to hatch, these nocturnal
fly predators effectively reduce pest fly populations by targeting the larval
stage of various fly species. These ant-sized insects fly inches off the ground
and do not bite, sting, swarm, or bother humans or animals.

Fly Exterminators will begin hatching 7-14 days after delivery, depending on temperature. Reduction in fly population should be noticeable approximately 3 weeks after hatching.

Dealing with a fly infestation can be stressful, unhygienic, an detrimental to your and your animals' quality of life. We offer monthly subscriptions that save your time and money.


        Cancel at any time.


      Small Animals (chickens, ducks, rabbits):

      100 Fly Exterminators per animal

      Medium Animals (goats, sheep dogs, cats):
      500 Fly Exterminators per animal

      Large Animals (horses, cows, pigs):
      1,000 Fly Exterminators per animal

      It's important to note that these introduction rates serve as general guidelines and may vary based on the specific pest species, the crop or plant being treated, and level of infestation. Proper monitoring of the infestation and the subsequent effectiveness of the released beneficial insect population is crucial for determining the success of the biological control strategy.

      Dealing with a fly infestation can be stressful, unhygienic and detrimental to your and your animals' quality of life, so start your Fly Exterminator program early! We offer monthly subscriptions that save you time and money. Plan your shipments during warm season to get ahead of a pest fly infestation.

      Keep Fly Exterminators indoors and in original packaging. Monitor daily for first signs of movement. Hatching can take 7-14 days depending on temperature. Pupae do not change in appearance after hatching. For optimal results, introduce within 24 hours of hatching.

      For maximum fly and flea control, release Beneficial Nematodes-Sc with your Fly Exterminators! Click Here to learn more!

    • Proper identification of the pest species is important. Monitoring the crop closely and introducing beneficial insects early will help in control pest populations.

    • Pesticides, even wetting agents, and spreader-stickers may adversely affect beneficial insects' survival. Broad spectrum and systemic insecticides are toxic.
      Every order includes hatching release bags to keep Fly Exterminators safely
      out of reach from birds and rodents. Our hatching release bags are beneficial
      for a number of reasons:
      • Target Application - The Hatching Release Bags are designed to ensure controlled and targeted application of the Fly Exterminators.

      • Easy Introduction - Hatching Release Bags provide a contained environment for the hatching and dispersal of Fly Exterminators. These tiny parasitoids are|smaller than an ant and can fit through the holes in the release bag after hatching.

      • No Mess - Hatching release bags are designed to minimize cleanup efforts, eliminating the need for post-application cleanup or the handling of potentially messy substances.
      Hang Hatching Release Bag out of direct sunlight. Height is not critical, but must be hung off the ground to protect from birds and rodents.
      Releasing Fly Exterminators is a simple process. We also offer subscriptions so you can stay on top of the pest fly lifecycle.


      You may see large numbers of flies around your animals, but the fly breeding area is most likely to be close to manure areas or other moist, rotting organic matter. These are the areas to release your Fly Exterminators.

      Top priority introduction sites include:

      • Barns
      • Stables
      • Kennels
      • Chicken Coops
      • Feedlots
      • Animal Straw Bedding

      Other potential introduction sites include:

      • Compost Piles
      • Garbage Cans
      • Septic Tanks
      • Near Water Sources (but not directly in water)
      Introduce monthly during warm months. Heavy infestations may require additional releases.

      Keep Fly Exterminators indoors, in original packaging, and out of direct sunlight. Monitor daily for first signs of movement. Hatching may take 7-14 days, depending on temperature, with the Fly Exterminators beginning to hatch at 70°F. Pupae do not change in appearance after hatching. For optimal results, release within 24 hours of hatching. Wait until temperatures are consistently over 50°F before releasing. These beneficial insects will self-distribute up to 100 yards.
        1. Locate fly breeding sites. Please see introduction sites above.
        2. Sprinkle Fly Exterminators near fly breeding sites and lightly cover to protect from birds and rodents.
        3. Locate other possible breeding sites and repeat.

            1. Locate fly breeding sites. Please see introduction sites above.
            2. Sprinkle Fly Exterminators in Hatching Bag (included).
            3. Secure the open edge with staples or clips to protect from birds or rodents.
            4. Hang above the ground, away from direct sunlight, near fly breeding sites. Hanging height is not critical.
            5. Locate other possible breeding sites and repeat.


            For best results, introduce immediately upon receipt. If storage is necessary, store unhatched pupae at 34-45°F for no longer than 5 days. After hatching, adults can be stored at room temperature, out of direct sunlight, for no longer than 3 days.

            Store Policies

            Please review our store policies below on Shipping & Processing, Live Delivery Guarantee, and Returns/Replacements. By placing your order, you are agreeing to these policies. Thank you!

            Thank you for shopping with us! No recommendation on pesticide use has been made by, or provided to, by the seller concerning the use of the pesticide covered by this website. Purchaser claims is for home use only and "not for commercial use".
            Shipping & Processing:
            Please allow 1-3 business days to process your order. At Natures Good Guys, we offer a variety of shipping methods for you to choose from when checking out after your purchase to give you flexibility. Overnight shipping and Second day are shipping services that we offer, however, choosing those services does not mean your order will ship the same day your order was placed. Overnight and second day shipping starts at transit time NOT when the order is placed.  While every effort will be made to expedite your order, we cannot guarantee same day order processing. Orders are shipped as quickly as possible and according to the availability of the product. Tracking information for UPS, USPS and FedEx deliveries will automatically be sent to your email if and when that information is available. 
            Harvest Delays:
            Please note that while we make our best attempt to keep all of our products in stock, nature sometimes thinks differently! We need to work with the natural reproductive cycles of living organisms, which means that on occasion your order will be delayed. Certain insects are harvested on specific days only, and sometimes our harvest will be delayed. In such a case, we will make our best attempt to send your order as soon as possible, or notify you through email or phone if there will be a significant delay.
            Overnight Shipping:
            We ship Overnight orders from Mon-Thurs and Second day orders from Mon-Wed (excluding holiday weeks/schedule varies), in order to prevent bugs from sitting in warehouses all weekend long and to assure their viability upon arrival. Second day orders will ship on Thursdays but only those whose address is Saturday deliverable. We do NOT ship Overnight and Second day orders Fri-Sun. USPS orders ship from Mon-Fri. Our cutoff time is 12 PM (pacific time). Please provide an email and phone number when placing your order, in case of a delay we will notify you to inform you about the delay and when to expect your order.  We DO NOT ship to PO boxes. We reserve the right to withhold shipments due to weather extremes or holidays.

            Due to the high volume of orders we process, we kindly ask that you notify us within 30 minutes of placing your order for any changes or cancellation requests. If you reach out to us after the order has already entered production, we will make our best efforts to accommodate your request; however, we cannot guarantee its feasibility at that stage.
            Live Delivery Guarantee:
            At NaturesGoodGuys, we are committed to providing you with the highest quality beneficial insects to enhance your gardening experience. Our Live Delivery Guarantee means that if you receive insects that are not viable upon delivery, you can contact us for a resolution.Simply email us at, providing your order number and a detailed description of the issue you encountered. We may require photos of both the insects and the packaging they arrived in. Our dedicated team will work diligently to address the problem and find a suitable solution.

            Please note that our Live Delivery Guarantee pertains specifically to the condition of the insects at the time of delivery and does not cover instances where insects may perish at a later stage.   We will exercise our discretion to assess whether your situation falls within the time frame qualifying for our policy. Factors such as the insect species, hatching time, temperature conditions, and other relevant considerations will be taken into account to determine the applicability of the guarantee. For non-hatching insects, you must contact us within 48 hours of delivery in order to be considered for the guarantee. Replacements will only be processed/shipped on Wednesdays & Thursdays.

            Upon receiving your package from NaturesGoodGuys, we highly recommend opening it immediately and checking for a sticker indicating the need for refrigeration. It's crucial to carefully read the instructions included for specific storage information to ensure the well-being of your beneficial insects. We are not responsible for replacements due to incorrect storage methods.

            One important thing to note is that we do not expect ice packs to remain frozen or cold upon delivery. Ice packs serve as a temporary measure to help maintain moisture and temperatures during transit.Please keep in mind that some insects may require time to adjust and recover from transit before they become active. If you don't observe immediate movement upon opening the package, this doesn't necessarily mean they are not viable. Give them a little time, and monitor for signs of activity as they settle into their new environment. Most of our insects are difficult to see without magnification.

            Some species/quantities do not have multiple shipping methods to choose from because they require short transit time for viability. For those who have concerns about the well-being of their insects during transit, we suggest selecting overnight shipping. This ensures that your beneficial insects spend minimal time in transit, reducing stress and maximizing their chances of arriving in optimal condition.
            If you have received an item that is damaged, defective or incorrect, please contact us immediately when you receive your shipment to resolve the problem. We do not typically ask for dead insects to be sent back to us, but replacements can be scheduled if the order is qualified, which is determined by customer support (please read our Live Delivery Guarantee). Please note that while we will happily replace packages that have been damaged, incorrect, or lost, we are not responsible for dead insects in the following situations:

            1. Customer input the incorrect shipping information: If the customer contacts our help line BEFORE their order has been processed to correct an address error we will be able to perform this change for you so that you can receive your order.
            2. Customer did not follow the instructions included with the shipped item: All of our items including our beneficial insects are shipped with instructions on proper use and storage (this can also be found on our website). Failure to follow the printed instructions or using a product other than for its intended uses will result in unsatisfactory results. Each case of unsatisfactory results are unique, therefore a customer service agent will help assess if the instructions were followed before any further actions can be taken on a claim.
            3. Customer's inability to receive the shipment in a timely fashion after delivery. If a customer is not home to accept the package when it is delivered, it is either taken back to the post office or left exposed to the elements in your yard or mailbox and this will cause stress to the insects, potentially resulting in insect death. Make sure that when you place an order you arrange a convenient time to be home to accept the shipment when it is delivered. We provide tracking information on all shipped orders so that the customer can be aware of when they should be expecting their order. Do not place an order you do not think you will be home to accept as we will not replace packages that die out of customer negligence.