Dear Jessica, I keep seeing ads for fly predators in horse magazines, but I'm a "check it out" kind of person and I don't know anybody who uses them. We have a lot of flies even though I clean stalls daily and pick out the paddocks and the pasture twice a week. I have six horses on six acres. The people in the ads all seem to be very happy about the results they get, but you can never tell if ads are for real. My neighbors on both sides of me have a couple of horses each and they are interested in the fly predators too. Can you tell me if they really work and if they are worth the money? I usually print out HORSE-SENSE for my neighbors because they aren't computer people, and they are big fans of yours. If you say that fly predators are worth buying then they will buy them too. They are the only neighbors with horses, nobody else out by us has horses but about three-quarters of a mile down the road there is a cattle farm. I don't think we get flies from there, it is a very clean place with about a dozen cattle, but if we did get fly predators (if they even work) would they still work if there is a farm that near by that doesn't use them? I get the impression that they are kind of like the feed-through wormers, they only work if everybody in the area uses them, but is that right or am I getting things mixed up? I have one more question (sorry), I have seen ads from two different companies for the fly predators, can you tell me which one is best? Anyway I will stop now and let you answer my questions which I hope you do. Thank you. Arlene
If the dozen cattle three-quarters of a mile away are the only other livestock in your area, and their owner keeps that property clean as well, then I don't think you need to worry about "visiting" flies. One of my neighbours has a dozen or so cattle that live about half a mile away from my horses, and there's never been a problem.
I don't think it really matters which company you patronize. As long as you get timely shipments containing a large number of live fly predators, you should be able to create a dramatic reduction in your farm's fly population.
Here are a few suggestions based on my own experiences with fly predators:
1. When you're calculating how many and what size shipments you'll need, be generous. If you have a severe fly problem, or if you have a lot of other horses or cattle nearby, you may want to get larger shipments, at least for the first year or two. Similarly, don't try to save money by being too precise with your scheduling. If your weather usually becomes hot sometime during June and your flies appear around that same time, and you schedule your first shipment of fly predators to arrive in early June, consider the possibility that your weather may become hot and your flies active in mid-May. It's hard to "catch up" when the flies have a chance to become well-established, so you may get better results if you get your first shipment several weeks or even a month before you would "normally" need it. (Has anyone else noticed that "normal" weather seems to be in short supply everywhere?) That earlier shipment is cheap insurance. If you have lots of flies, the fly predators can get to work. If you only have SOME flies, the fly predators can get to work on ALL the larvae - and you may have an even more dramatic drop in the fly population! Hot weather can arrive early, and it can also linger... so it may be equally useful for you to tack on an extra shipment at the end of the season, just in case. Again, it's cheap insurance.
2. Be sure that any helpful person who says "I'll dump the fly predators for you" understands where and how to "dump" them, and knows that they need to be released where there is manure, and that it's best to kick a bit of manure over them once they've been released.
3. Don't be discouraged if you've used fly predators all summer and just haven't noticed a big reduction in flies. By the end of NEXT summer, you will probably notice a big reduction, and an even bigger one the year after that, etc. If your summer weather began early and your winter arrived late, you may want to improve your odds for next year by changing your order: start a little earlier, end a little later, buy more fly predators. You may also find that changing the delivery schedule helps - on my own farm, I get much better results with shipments every three weeks than with shipments every four weeks.
4. Don't be discouraged if, at the end of your second summer, you're still not sure that you're seeing a big difference. It may be that you're having a really horrible year with high temperatures, high humidity, and many more flies than usual - in which case it's entirely possible that the fact that you haven't noticed a huge INCREASE in flies is proof that your fly predators are working. Before you decide to give up, go and visit someone in your area who has a similar setup in terms of environment and number of horses, but who DOESN'T use fly predators. If you are horrified at the incredibly high number of flies on that person's property, then go home and relax because you don't have anything like that number of flies, you may realize that you actually ARE getting good results. And if you want even better results, see suggestions #1 and #3.
5. You may want to use a few methods of fly control in addition to your fly predators - but be careful. Not all fly larvae are consumed by fly predators - just ones that on the ground (e.g. in the corners of the stalls, on the manure pile, and wherever your horses eat, drink, or eliminate). If you have some types of flies that deposit their larvae elsewhere, you may want to invest in fly traps as well. Traps are generally preferable to sprays, because not only do they target the adult flies, they target ONLY the flies themselves, whereas many fly-spray products will kill the fly predators as well as the flies! Some products won't harm them, but if you're in any doubt, it's best to call or e-mail the company and ask which products you should and shouldn't use.
6. WATCH YOUR MAILBOX. If you have a farm, chances are that your mail is delivered to your mailbox out by the road, and not to your door. It's important for you to know when your mail is delivered, and be sure to check it immediately, whenever you're expecting a new shipment of fly predators. In extremely hot weather, spending a few (or many) extra hours in a hot black mailbox in full sun can COOK the poor little predators.
7. If, in spite of your best efforts, your fly predators don't show signs of life (follow the company's instructions for monitoring their condition and knowing when to distribute them), it's very possible that they were "cooked" in transit - when the temperatures are in the 90s and a shipment sits in a hot truck or on a hot siding, fly predators may die. Call or write the company as soon as possible, and ask for a replacement shipment. Both of the major fly predator suppliers, ARBICO and SPALDING, have been very quick and cooperative on occasions when fly predators have been DOA.
8. Finally, whatever you do, don't give up too quickly. I didn't notice a huge change in our fly population after the first year, but there was an obvious reduction in the second year, and a greater reduction every year since then. I wasn't sure what to expect when I first ordered fly predators, but now I can't even imagine NOT using them.
Back to top.
Jessica Jahiel's HORSE-SENSE is a free, subscriber-supported electronic Q&A email newsletter which deals with all aspects of horses, their management, riding, and training. For more information, please visit www.horse-sense.org
Please visit Jessica Jahiel: Holistic Horsemanship® [www.jessicajahiel.com] for more information on Jessica Jahiel's clinics, video lessons, phone consultations, books, articles, columns, and expert witness and litigation consultant services.