Beekeepers worry about parasites killing their bees

SPOKANE – Bob Arnold’s bees move fast in the warm weather, buzzing from flower to flower and then back to their hive.

The insects’ bodies are covered in pollen as they gorge themselves on clover and other flowering plants.

Dressed in white coveralls, Arnold wades into a cloud of bees on a farm a few miles north of Deer Park. The beekeeper doesn’t bother with screens and other anti-stinging gadgets: “They’re too busy to care about me right now,” he says, calmly checking his hives.

The honey is beginning to come in, an exciting time for beekeepers. But Arnold has concerns, too, for his industrious little workers.

He keeps millions of bees, as he has done for more than 30 years. But the business keeps getting more difficult and expensive because of two parasites that are killing off honeybee populations across the United States.

“They’re getting the best of us,” Arnold sighed.

As Arnold lifted a bee-covered flat from a white bee box, he brushed some of the bees away and set it on the bed of his pickup.

He sliced into a honeycomb cell and removed a larva that would have emerged a drone, a male honeybee with the single-minded purpose of mating with the queen.

Trouble with mites

A closer look at the creamy white larva wriggling on Arnold’s leathery hand revealed the problem: It appeared to have a freckle.

This reddish-brown spot was actually a mite of pinhead size that has been ravaging honeybee populations for two decades and threatens important crop pollination across the U.S.

Honeybees pollinate a third of the human diet – more than 50 crops valued in excess of $20 billion, according to the U.S. Department of Agriculture’s Carl Hayden Bee Research Center in Tucson, Ariz.

That includes almonds, apples, peaches, pears, cherries – most things that are grown to eat besides grains and potatoes.

There are two types of mites wreaking havoc.

One is the tracheal mite. It was discovered in Europe and arrived in the U.S. from Mexico in 1984. It crawls into the throats of honeybees to lay eggs, and the hatch feeds on the bee’s blood.

The other, such as the one Arnold pointed to, is the varroa mite. It was first identified in Java a century ago and was believed to have arrived in the U.S. in 1986 in a smuggled colony of Asian bees.

Widespread problem

It has been the most devastating, wiping out both wild honeybees and European honeybees in alarming numbers across all 48 contiguous states. Its spread has been aided by the migratory nature of beekeeping, which begins when beekeepers deliver bees to orchards in Southern states and then steadily haul them north. These mites live in the bee hives, attaching themselves like ticks to larvae and adult bees alike.

Ted Swenson, a longtime beekeeper in Spokane, said some commercial beekeepers have to replace most of their hives every year because of the varroa mite’s destruction. This past winter, Swenson said 50 percent to 70 percent of honeybee hives in Washington state and the rest of the country were lost.

Now, beekeepers are being hit with a double-whammy: the varroa mites are transmitting a virus.

The story of mites in the honeybees is nothing new. And beekeepers face many of the same pressures as others involved in agriculture. Costs are going up; the price of honey is abysmal, below $1 a pound; and low-cost imports from other countries offer tough competition.

But honeybees, with their six-week life span, are especially fickle.

During the warm months, they go and go until their wings wear out, building the waxy comb for the queen to lay her eggs, guarding the hive and producing honey.

Although beekeepers have learned to treat their hives for mites, the varroa parasites have shown a quick ability to adapt.

Treatments have included pesticide strips placed directly in the hives. Called Apistan, the pesticide strips have worked well, but not perfectly. Now, the few mites that have survived have passed on a resistance to the treatment, making the strips less effective.

Scientists at research laboratories, including at Washington State University in Pullman, have developed new treatments, including the use of formic acid. It works well killing mites, but it’s also hard on the bees, said Swenson.

“Everyone is careful about using it because it can affect the honey or kill the bees, and that’s not acceptable,” he said.

Swenson holds out hope for breeding resistance into bees to combat the parasite. Though African bees show a greater resistance to the mites, they are much more aggressive, making them difficult to handle, and frankly, less tolerated by the public.

Learn to deal

He doesn’t think the mites will ever be eradicated.

“Like any insect, they won’t be wiped out. You have to learn to live with them,” he said.

The mites’ toll on honeybees has led to worry in California’s important almond industry. This year, for the first time, there weren’t enough bees to pollinate all of the almond blooms, so honeybees from Australia were imported to finish the job.

It’s estimated that there could be 750,000 acres of almonds in California within five years. Pollinating that much acreage would require more than half of all the working honeybees in the United States.

As the mites take their toll on domesticated honeybees, they have also devastated the population of wild honeybees, the reliable friend of gardeners and farmers.

The number of native bees has dropped by 90 percent, according to some estimates, because of the mites and viruses.

While frenzied stories of African killer bees attacking people and pets make compelling headlines, it’s the plight of honeybees that has the potential to affect most people, from orchardists to backyard gardeners.