Utilizing Parasitoids for Fly Management

You’ve little doubt heard the outdated adage, “battle fireplace with fireplace.” An analogous line of pondering can be utilized for utilizing parasitoids for fly management by combating bugs with bugs.

Also called organic management, this idea makes use of the pure tendency of 1 insect species to assault one other at particular phases of improvement. For instance, there are parasitic wasps that lay their eggs within the pupae of sure flies. As these eggs hatch, the wasp larvae feed on the creating flies within the pupae, killing them.

Additionally known as parasitoids, these tiny wasps are discovered within the wild, however naturally occurring numbers aren’t often sufficient to make a big dent within the fly inhabitants, which is why corporations promote parasitoids particularly for fly-control functions.

Erika Machtinger, Ph.D., assistant professor of Veterinary Entomology at Pennsylvania State College, has been working with parasitic wasps for a decade and refers to them as “the ninjas of the fly management world.”

These nocturnal, gnat-sized bugs don’t chew or sting animals or people, however they’re lethal to creating flies.

Getting Began

In the event you’ve had a fly downside prior to now and are decided to strive one thing completely different this yr, it’s essential decide the fly species you’re coping with earlier than utilizing parasitic wasps.

“These parasitoids will truly [attack] many alternative species of flies, together with fruit flies, however normally, they’ll primarily assault what we name ‘filth flies,’ which embody secure and home flies,” explains Machtinger.

Black flies, deer and horse flies, biting midges, and mosquitoes don’t develop in manure and waste materials like filth flies do, so parasitic wasps gained’t management them. In addition they aren’t efficient towards face flies, as a result of face flies have calcified pupae that the parasitoids can’t get into.

Earlier than you start, be sure the goal flies are creating in your property, not your neighbor’s. Some flies can journey 2 to eight miles from their improvement websites, so for those who dwell close to a poultry or cattle operation, your fly downside could also be coming from these farms. If that’s the case, releasing parasitic wasps in your property gained’t be efficient.

Firms advertising parasitoids usually promote a number of species within the genera Muscidifurax and Spalangia. If you contact an organization, they’ll decide which species will likely be simplest in your space and arrange a cargo schedule.

“Within the wild, one genus known as Spalangia are discovered extra within the South, and Muscidifurax extra within the North, however usually most of those parasitoids can work wherever they’re launched,” notes Machtinger. “There are some which can be presently marketed known as Nasonia that don’t work for controlling filth flies, so it’s vital to ask your provider what they’re promoting.”

Launch

Timing and launch are key to success when utilizing parasitoids for fly management. Ideally, it is best to time your first launch of parasitic wasps previous to fly season.

“This provides the parasitoids time to assault any flies which can be presently creating and stop an outbreak,” says Machtinger. “When you have a bunch of flies already, it’s possible you’ll want extra than simply parasitoids to assist scale back the inhabitants.”

When you join with a industrial supplier, you’ll obtain your order periodically all through fly season, akin to each two to 4 weeks.

Grownup parasitoids wouldn’t survive delivery and dealing with, so the businesses ship them as they’re creating. You’ll obtain a sealed bag of sawdust containing home fly pupae which were parasitized. As a result of they arrive from the laboratory, there’s no concern of flies rising from any of the pupae.

Comply with the particular directions that include your order.

Maintain the bag at room temperature away from direct daylight. By holding the bag as much as mild, you’ll be able to inform when the grownup wasps begin rising, which must be inside a pair days.

Launch in accordance with offered instructions, avoiding scorching mid-day temperatures, and windy or wet circumstances. The supplier usually instructs that they be launched on or proper round manure areas.

“You have to be sure to are releasing them the place flies develop since they aren’t good fliers,” says Machtinger.

One Piece of the Puzzle

Parasitoids are completely pure and non-chemical, however you’ll be able to’t depend on them alone to regulate flies, as flies have a a lot increased reproductive charge. Nevertheless, they are often an efficient a part of your fly administration plan when mixed with such sensible measures nearly as good sanitation and common manure elimination.

“I wouldn’t go a summer season with out them; it’s made an enormous distinction,” says Kathryn Wade, who has two horses and a donkey on her 5½-acre property exterior Tucson, Ariz.

“It helps to contain horse-owning neighbors close by so you’ll be able to all use them,” provides Wade, who has been utilizing parasitoids for six years.

She notes that manure administration can be essential. Wade cleans her corrals day by day and hauls manure off the property weekly.

Watch Insecticide Use

Clearly, parasitic wasps are bugs, making them susceptible to pesticides. Since they spend most of their time within the habitat the place flies are creating, they need to be protected until you instantly apply pesticides to the realm the place they’re launched.

Some farms make the most of spray techniques to mechanically disperse misting insecticide within the barn, however it’s possible you’ll need to rethink this technique.

“I strongly advocate towards computerized sprays within the barns, even these utilizing ‘pure’ compounds,” cautions Machtinger. “Not solely do these not work to kill flies, they assist promote insecticide resistance and expose animals and other people to chemical substances within the setting.”

This text about parasitoids for fly management appeared within the March 2021 difficulty of Horse Illustrated journal. Click on right here to subscribe!