To Treat or Not to Treat for Varroa Mites

Varroa mites (appropriately classified as Varroa destructor) are nasty little parasites that attach to bees’ bodies and weaken them by sucking out body fat. Varroa mites are a vector for a least five debilitating bee viruses. 

These mites were first discovered in the United States in 1987 and quickly caused panic among both beekeepers and researchers. Their fears were well-founded. Eradication proved ineffective, and the mites inexorably spread to almost every beehive across the continent. Without any innate resistance or tolerance, even the most organic-minded beekeeper turned to pesticides to save their hives. 

Varroa mites are so prevalent that many beekeepers now categorize hives containing four types of insects: queen, workers, drones, and mites. 

But amidst the myriad of advice, pesticides, invasive treatments, and other methods for treating varroa mites, a hardy group of pioneers stands out: Those who refuse to treat the mites at all. 

What, Are You Nuts? 

The thought of leaving varroa mites untreated strikes many commercial beekeepers as crazy. For this reason, it’s the non-commercial beekeepers who are most likely to travel this unorthodox path. 

Consider Dave and Dezi, small-time apiarists in Northern Idaho who currently have 55 hives. They’ve been keeping bees for ten years and have learned a tremendous amount — including questioning the practice of treating varroa mites. They have not treated for the last five years. 

Dave and Dezi scientifically came to their decision. During their first year as beekeepers, they had eight hives. They treated four with oxalic acid, and the other four they left untreated. “There was no difference,” Dave concluded. 

Oxalic acid — a natural, organic antibiotic compound found in many plants — is one of the more popular varroa mite treatments and is generally applied as a vapor. The vapor is released into the hive, where it adheres to the inside surfaces as it cools. Mites come into contact with the acid, and there is usually a high death rate within the first two days. 

There are many other management techniques available for varroa mites, including natural treatments such as dusting with powdered sugar or essential oils, but nothing is guaranteed to work. Varroa mites are here to stay whether or not beekeepers like it — or whether or not hives are treated. 

Dave and Dezi did not want to be dependent on oxalic acid or any other treatments for the survival of their hives. Instead, they began selecting for hives that survived untreated and started splitting those healthy hives to increase the natural resistance of their populations. 

“Survivability continued to get better,” Dave said. “At first, we had 60% losses, then 40%, then it dropped into the 20 to 30% range.” In short, Dave and Dezi’s hives still have varroa mites, but not as many hives succumb to them. 

To Treat or Not to Treat 

Dave admits there are some repercussions for beekeepers who do not treat. “Definitely, they’ll grow their business more slowly,” he says. “You have to build your own genetic strain of bees that can survive in your own climate. Initially, it will be a struggle.” 

Dave and Dezi understand that struggle. It took them several years to build up to a healthy 55 hives. They breed their own queens and control their own strain. 

“We focus on genetics,” Dave says. “We look for traits that will survive the winter. We don’t necessarily breed for docile hives. We prefer cranky bees that will survive over docile hives that won’t.” 

This attitude of maverick backyard apiaries encompasses the heart of what’s called “natural” beekeeping methods. These apiarists are more interested in raising bees that can thrive, not bees that are artificially propped up with miticides or oxalic acid or other treatments. 

As Michael Bush at Bush Farms (bushfarms.com/beesfoursimplesteps.htm) puts it, “[U]ntil you quit treating, you can’t breed for survival against whatever your issues are. As long as you treat, you prop up weak genetics, and you can’t tell what weaknesses they have. As long as you treat, you keep breeding weak bees and super mites. The sooner you stop, the sooner you start breeding mites adapted to their host and bees who can survive with them.” 

Advice for Backyard Beekeepers 

When asked what advice Dave and Dezi would give to backyard beekeepers, Dave had firm opinions. “Learn to raise bees. Don’t learn to harvest honey,” he emphasized. “You can buy honey anywhere. But for the first four or five years, let the bees keep all the honey, especially in colder climates.” 

Dave says the days of having just one or two hives are gone. “With pest pressure — especially Varroa mites — one or two hives aren’t enough. I have yet to see a beekeeper with one or two hives survive. They’re buying bees year after year.” 

Instead, he advises backyard beekeepers to keep between six and 10 hives, which gives both a product and some wiggle room when there is a 50% loss. “Split and rebuild your hives,” he advises, then repeats: “Learn to raise bees, not honey.” 

Speaking for cold-climate beekeepers, Dave urges apiarists to run three deep brood chambers. “Try to get hives up to 100,000 bees. A queen that can lay 800 to 1200 eggs per day needs that deep brood, and it leaves them with 80 to 100 pounds of honey per year. It’s a slow, painful, and expensive project, but first, learn to raise bees. Then the honey will follow.” 

At this stage, the decision not to treat varroa mites is considered controversial and unorthodox, maybe even radical. It’s the maverick backyard beekeepers who are at the forefront of this trend. Usually, commercial beekeepers can’t afford to take the risk. 

In this regard, perhaps it’s the backyard beekeepers who are the future of beekeeping. They’re the ones who may provide the means for the industry to handle varroa mites without treatment. 

Originally published in the August/September 2021 issue of Backyard Beekeeping and regularly vetted for accuracy.