Tuesday, May. 28, 2024

Effective, Eco-Friendly Fly Control Explained

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Finding the balance between effective and eco-friendly sometimes feels like a compromise. Harsh chemicals can get the job done, but at what health and environmental cost?

Jessica Starcevich, Chief Science Officer at Spalding Labs, breaks down the advantage behind natural, biological fly control and explains how to use it efficiently.

Comparing Efficiency

There is no perfect silver bullet, natural or chemical, that can solve a pest problem like an overabundance of flies. The better approach to dealing with any pest situation is through Integrated Pest Management (IPM).

“Think of IPM as a holistic approach using a combination of techniques and products in conjunction with each other so that the end result is good pest control with a minimal use of chemical controls,” explains Starcevich. “Minimizing chemical use not only helps reduce effects on non-target organisms, but also helps reduce the chance of the pest developing resistance.”

In the same way bacteria can become resistant to overused antibiotics, so too can pests like flies become resistant to overused chemicals. For fly control, this means using a combination of sanitation practices, biological control (like Spalding Labs’ Fly Predators®), traps and potentially targeted sprays.

Most horse owners’ current IPM does not include beneficial insects, making them the “missing piece” to their current fly control program and the reason they still have flies.

Targeted Natural Protection

We know that “eco-friendly” means not harmful to the environment, but what advantage does that provide when we’re talking about fly control? A big one!


Using natural fly control methods to reduce or eliminate the need for chemical control options helps reduce the harmful effects chemicals can have on non-target organisms, or animals and insects that are unintentionally affected. For example, a sprayed pesticide will kill insects such as dung beetles which help break down manure and fertilize pastures as well as pests such as flies.

“With something like Fly Predators® which are a very host-specific, biological fly control option, we eliminate that danger to the non-target organism,” continues Starcevich.

Beefing Up of Biological Fly Control

Fly Predators® are a type of tiny wasp that both feeds directly on and parasitizes the pupal stage of the fly. They’re a mix of three species (Muscidifurax zaraptor, Muscidifurax raptorellus, Spalangia endius and

Spalangia cameroni) that have performed well in the field and whose efficacy is backed by many peer reviewed studies. Each species has an important niche—the Muscidifurax species handle cooler temperatures better and search closer to the surface when seeking fly pupae. Spalangia species can handle hotter temperatures and search deeper into the substrate when seeking out fly pupae.

Fly Predators® in the Wild

Although you may not see them, the species that make up Fly Predators® do exist naturally throughout North and South America. We never notice them due to their tiny size and the fact that they spend most of their life burrowing through substrates looking for fly pupae. They look a bit like a very tiny ant and will never get any larger.

Fly Predators® are very host specific, meaning they are only able to kill and parasitize just a few species of flies, primarily house flies (Musca domestica) and stable flies (Stomoxys calcitrans). They are completely unable to harm other species such as beneficial black soldier flies (Hermetia illucens) or even other nuisance flies such as deer flies (Chrysops sp.). Fly Predators® will not harm any species of bees, including honey bees.

If domestic or wild animals eat Fly Predators®, they wouldn’t get any more than an itsy bit of extra protein. Eating a Fly Predator® is no different than if they ate something like a cricket. This makes them safe for pets, horses, livestock and wildlife in the ecosystem surrounding your barn.


Preventative Predators

“Fly Predators® help control fly populations by killing flies like house flies and stable flies before they hatch, so you can think of them as a preventative,” explains Starcevich.

Flies are important in nature because they are major decomposers of decaying organic matter, which is something our horses can create a lot of! As humans, we don’t much care for the abundance of flies. Receiving shipments of Fly Predators® regularly throughout the fly season helps force the Fly Predator® populations to remain much higher than they normally would in nature, leading to lower overall fly populations. Typically, properties with fewer than 50 large animals or the equivalent would receive shipments every three weeks for the best control.

Eyes on the Flies

Fly Predators® and improving sanitation practices can manage most house and stable fly problems. However, other factors can also play a role in success, such as proximity to other animals, unexpected weather events and changes in routine. These other factors could create a need to put some traps on a property line to intercept flies immigrating from other nearby animals, using traps to reduce adult populations blown in on storm fronts or adding extra Fly Predators® when there is a lot of rain (and thus better breeding potential for flies). An increase in the fly population usually occurs seven days after the

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extra rain, so having an extra shipment of Fly Predators® on hand to release before the increase in flies can help keep the bugs at bay.

“Having an IPM program in place can keep you prepared so that you can quickly react to any extra factors that might be contributing to your fly problem,” concludes Starcevich.

Don’t struggle with flies another season—learn more about Fly Predators and other Spalding Labs eco-friendly fly control solutions at FlyPredators.com

***Advertorial: COTH staff did not create this content***




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