The Colony-Killing Mistake Backyard Beekeepers Are Making

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Jonathan Garaas has learned a few things in three seasons of backyard beekeeping: Bees are fascinating. They're complicated. And keeping them alive is not easy.

Every two weeks, the Fargo, N.D., attorney opens the hives to check the bees and search for varroa mites, pests that suck the bees' blood and can transmit disease. If he sees too many of the pinhead-sized parasites, he applies a chemical treatment.

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Garaas has lost hives in his first two years as a novice beekeeper. But with nine hives now established near his home and a couple of University of Minnesota bee classes under his belt, he feels like he's got the hang of it, although it's still a challenge.

"You can get the book learning. You can see the YouTubes. You can be told by others," he says, but "you have to have hands-on experience. When you start putting it all together, it starts making sense."

Scientists wish every beginner beekeeper were as diligent as Garaas.

While experts welcome the rising national interest in beekeeping as a hobby, they warn that novices may be inadvertently putting their hives — and other hives for miles around — in danger by not keeping the bee mite population in check.

Many hobbyists avoid mite treatments, preferring a natural approach, says Marla Spivak, a bee expert at the University of Minnesota. But that's often a deadly decision for the bees, she says.

National surveys by the Bee Informed Partnership show backyard beekeepers are taking the greatest losses nationally, and those losses are often the result of an out-of-control infestation of the varroa mite, says Spivak.

Varroa mites arrived in the United States nearly 30 years ago, and they've become a big problem in recent years.

Untreated hives can spread mites and viruses to other hives within several miles, Spivak says. Healthy bees will invade a dying hive to steal its honey. When they do, they carry the mites with them back to their hives.

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"The combination of the mite and the viruses is deadly," says Spivak.

The University of Minnesota Bee Squad, a group that provides beekeeping education and mentoring in the Twin Cities, is seeing more healthy hives become rapidly infested with mites and the viruses they carry.

Fall is an especially critical season, says Rebecca Masterman, the Bee Squad's associate program director.

"That late season reinfestation means that bees are going through winter with a lot of mite pressure and it's really hard for them to come out of that and survive," she says. "It's important enough to really try to get every backyard beekeeper in the country to at least be aware of it."

Masterman says she's also encouraging commercial beekeepers to check their bees more often for surprise mite infestations. A new online mite-monitoring project lets beekeepers anywhere in the country share data on infestations that will help researchers track the spread.

A mite control experiment this summer should provide more information about how to best treat mites in bee colonies.

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Bees face other challenges beyond mites, including poor nutrition, disease and pesticides. Even veteran beekeepers say it takes more effort to keep their bees alive these days.

But the mite and virus threat to bees is something that can be controlled, says Spivak.

"I really understand why some people might not like to have to treat their bee colony for mites. It just sounds so awful. It's such a beautiful bee colony and to have to stick some kind of a treatment in there seems so unnatural," she says.

"But our bees are dying. And it's very important to help do whatever we can to keep them alive."