Exploring an enigma

Keith Delaplane leads a team of experts investigating the mystery of honey bee decline

Exploring an enigma

A queen bee (center) crawls on a section of hive at UGA’s Honey Bee Laboratory in Watkinsville. In today’s market, a queen is worth about $25.

Photo by: Peter Frey

It’s a beautiful spring morning in March, and Keith Delaplane is cracking open a hive at UGA’s Honey Bee Lab. He puffs smoke into the hive to “let them know we’re coming,” then uses a small metal tool to pry open the edges, which are sealed together with beeswax. As he lifts frames from the hive—they look like small window screens hanging inside a wooden banker’s box—he plays tour guide.

Entomology Professor Keith Delaplane directs UGA’s Honey Bee Program and leads a team of researchers working to identify the cause of honey bee decline. The lab at UGA includes 30 to 40 hives, with more located in other Georgia counties.

“There’s a baby bee just emerged,” he says. “You can tell because she’s white, kind of pale. She’s probably only minutes old.”

He uses the corner of the hive tool to scrape honey from a cell, tastes it, and then points out the pollen.

“Do you see how they layer it?” he asks. “Each layer represents one bee trip. They unpack it in there, and then they use their little heads like battering rams and pack, pack, pack.”

He points out drone brood that are turning from larvae into pupae, a thorax and abdomen becoming visible, and young larvae, white grubs that look like a letter “c.” After pulling out a few frames he finds the queen, who is noticeably larger than the rest.

“You can see all those eggs she’s cranking out,” he says. “That’s all those empty cells—the little white dot at the bottom of each one is an egg.”

Delaplane, who is not wearing protective gear, is relaxed despite just opening a hive of about 25,000 bees. The sun is shining and skies are blue at the lab, which is tucked behind the university’s horticulture farm in Watkinsville. Although he shows no signs of stress, appearances can be deceiving. Delaplane is in his fourth and final year of heading a national consortium tasked with finding the source of honey bee decline. Both politicians and beekeepers are looking to him for answers, but what they really want is a smoking gun.

A few minutes later, Delaplane finds one dark spot that mars this lovely morning.

“Oh! There’s one. See that black dot?” he asks. “That’s a Varroa mite. That is problem number one.”

A Varroa mite crawls on the back of a honey bee at the UGA lab.

In 2006 beekeepers began reporting that once-thriving colonies of honey bees were being abandoned overnight. The phenomenon that became known as Colony Collapse Disorder (CCD) was unusual because no dead bees were found outside the hives—the bees simply vanished. Beekeepers reported losing anywhere from 30 to 90 percent of their hives. Such dramatic losses spurred continuing press coverage, particularly when no single cause for CCD could be identified. But honey bees were already on the decline before CCD. The number of managed honey bee colonies has dropped from 5 million in the 1940s to 2.5 million today, according to the U.S. Department of Agriculture’s Agricultural Research Service (ARS).

This decline is significant because honey bees pollinate $15 billion worth of crops annually. That includes fruits, nuts and vegetables that humans eat as well as animal-feed crops, like clover that’s fed to beef and dairy cattle. The ARS estimates that one-third of our diet benefits directly or indirectly from honey bee pollination.

Delaplane puts it more succinctly. Look at a McDonald’s cheeseburger, he suggests.

“If you take away everything a bee pollinated, you’re not left with much,” he says.

“If you take away everything a bee pollinated, you’re not left with much.”

What’s left is the bun. No burger. No cheese. No ketchup. No mustard. No dill pickle. No onion.

We wouldn’t starve without honey bees, but our diet would be a lot less interesting, Delaplane says.

“At some level, mere survival of humanity, pollination is pretty superficial. However, once you move beyond survival, then you start invoking honey bee pollination. Let’s go beyond a bowl of rice. You don’t need bees for that,” he says. “What about the fruits and the vegetables? Well now you’re starting to talk about pollination. At this point you’re talking about the flower, which produces a fruit, and that can be anything from a succulent tomato to an almond nut.”

“That’s what’s at stake. It’s not human survival—that’s melodramatic. But it is the quality of food that we enjoy and the quantity of it. If you don’t have pollination to produce those things, you’re going to see supply go down and prices go up.”

Honey bees are not the only pollinators available, but they are the best option for an industry that requires enormous input. Consumers expect fruits and vegetables to be available all the time, so every year commercial beekeepers haul their colonies across the country to pollinate everything from almonds in California to blueberries in Maine.

“Because we have such high concentrated food production needs, you’ve got to have high concentrated pollination inputs as well,” Delaplane says. “The honey bee remains the only pollinator that we can manage at a factory scale.”

But large-scale pollination means intermingling and potential exposure. Whatever honey bees are exposed to is taken back to their hive, making them vulnerable.

“It’s just a perfect recipe for disease transmission,” he says.

Keith Delaplane was a 13-year-old boy growing up on an Indiana farm when his father bought him a beekeeping kit. It was an out-of-character move for the farmer, who expected his son to spend time helping with the corn, soybeans and hogs they were raising.

“The bees arrived, and I got totally caught up with it,” Delaplane says. “He could never understand why I’d be wanting to ‘fool around with them bees.’ He had more important work he needed me to do.”

But it was portentous, Delaplane says, because the bees came from Georgia.

“It was a sign,” he whispers conspiratorially, with a smile.

Delaplane earned a bachelor’s degree in animal science at Purdue University, then studied entomology at Louisiana State University, earning both a master’s degree and a Ph.D. In 1990 he arrived at UGA, where he is a professor of entomology and director of UGA’s Honey Bee Program.

Beverly Sparks, associate dean for extension at UGA’s College of Agricultural and Environmental Sciences, has watched Delaplane build a strong program that provides help for beekeepers in Georgia and beyond.

“He just stays right out there on the forefront of the problems, and then comes up with solutions for them,” she says.

ARS Research Scientist Jay Evans says Delaplane is well respected by scientists but also by the beekeeping community.

“Very few bee researchers and professors have been able to pull off a book [First Lessons in Beekeeping, published in 2007] that’s interesting for the beekeepers themselves,” he says.

Delaplane is the national director of the $4.1 million Managed Pollinator Coordinated Agriculture Project (CAP), funded by the USDA’s National Institute of Food and Agriculture. The team involves 17 cooperators and institutions from coast to coast, a consortium of scientists and educators working to reverse honey bee decline.

He jokes that he’s the “janitor” of the project, spending all of his time on budgets and writing reports, but Evans—who’s a member of the CAP team—says that Delaplane conceptualized the project, pulled the team together and continues to guide the big picture.

Beekeepers Ben Rouse (left) and Nicholas Weaver split a hive at UGA’s lab. Splitting hives prevents them from overpopulating and keeps bees from swarming to a new home.

“It’s pretty tough to corral 20 scientists into doing something together, and I think he’s got a good gift for doing that,” he says.

And Delaplane easily describes some of the teams and their assignments. At the University of Maine is the epidemiologist who’s coordinating all the experimental data and putting it into models. Researchers at the University of Massachusetts are looking at other pollinators, investigating the possibility of cross-species infection. Pennsylvania State University is handling the genetics of the Nosema parasite and taking the lead on toxicology. Purdue University is working on genetic selection for resistance to the mite known as Varroa destructor. The University of Tennessee is taking the lead on the project’s Bee Health website, a one-stop shop for the latest information.

Now in the final year of this project, Delaplane feels the weight of expectations.

“It’s expected that we will come out with answers to actually help the beekeeping industry,” he says, but adds that the answer is likely to be just as complicated as the problem.

“From the beginning we knew that this was not going to be a smoking gun, single cause, simple model,” he says.

Delaplane believes that we’ve been conditioned by the medical field to expect a linear process—symptoms, causation, cure. But investigating honey bee decline, on the contrary, has led to the growing awareness of a multiplicity of factors.

“It’s still important for us to pick that puzzle apart, and that’s what we’ve been doing,” he says. “But it is inherently longer and more difficult to do those kinds of investigations.”

There are a number of people—politicians wielding purse strings and beekeepers with their livelihoods on the line—waiting impatiently for Delaplane and his team to come up with answers. His father is not one of them. “He still, to this day, doesn’t really understand what I do,” Delaplane says, chuckling.

“He still thinks bees are kind of foolish.”

The presence of Varroa mite in the hive opened this morning seems, to borrow Delaplane’s word, portentous. Because he believes there is no one single cause for honey bee decline, but he’s convinced that Varroa mite is at the top of the list of problems. He’s not alone. At least three international symposia on this topic have been called in the last 16 months.

Varroa destructor spreads and activates viruses, compromising the honey bee immune system. It’s native to Asia, but has been in the United States since 1988.

“I call it the snowball that starts the avalanche. It’s always at the top of the list,” he says. “If there was one thing I could wave my magic wand and cure, it would be Varroa mite. If we could get rid of Varroa mite, I think the headlines would cease.”

Some members of Delaplane’s CAP team are working to address Varroa mite by using RNA silencing technology, the process of inserting genetic material that blocks the production of proteins or other materials needed to live—killing the organism.

Others are narrowing down a list of viruses that may be problematic. They started with 10 and have narrowed it down to four. And the Nosema parasite, once thought to be a significant factor in honey bee decline, has been downgraded.

One of the team’s most significant findings involves what happens when hive chemicals—added by beekeepers to control parasites—interact with agricultural pesticides. One particular hive chemical is deadly when combined with a common agricultural fungicide.

“Both of these chemicals by themselves are innocuous to the honey bee, but you put the two together and this horrible synergy happens that’s just lethal to bees,” he says.

Here’s the question that keeps Delaplane up at night: What if his colleague had picked another chemical combination to test?

“What other combinations are out there that we’re blissfully ignorant of? That’s what we’re up against—trying to look at all the possible permutations in nature and agriculture and make this into some kind of recommendation,” he says. “It’s more like forensic science than experimental science. It’s more like Sherlock Holmes on the scene of a crime than it is a scientist in a white lab coat.”

When he was young, Delaplane read and enjoyed James Herriot’s books known collectively as All Creatures Great and Small. The stories were semi-autobiographical tales of an English veterinarian’s experiences caring for patients of every size in the Yorkshire countryside. In May, he traveled to York for a six-month study leave at England’s national honey bee lab.

It’s “almost like a pilgrimage to go back and see it,” he says.

While in York Delaplane is studying diagnostic techniques for viruses, catching up on the genomics revolution that has happened since he finished grad school. And he continues to lead the CAP team toward a resolution that he suspects will be unsatisfying and even frustrating for some.

Delaplane points out details of a hive to SPC Carl Chandler and Command Sgt. Maj. Randall Parker, members of the Agribusiness Development Team from Fort Gordon, Ga., during the Georgia National Guard Agricultural Training in February 2011.

“When I talk in front of crowds, especially beekeepers, I say, ‘Well, you know, it’s a multifaceted issue,’ and you can just see their eyes glaze over,” he says. “And I can appreciate that. Just because something is hard and multilevel doesn’t get us off the hook.”

Ultimately the answer to honey bee decline is going to be addressing a number of big issues like Varroa mite and viruses, but also making policy changes at the level of the Environmental Protection Agency (EPA), he says.

“We still have farmers that’ll go out and spray a crop that’s blooming. If it’s blooming the bees are coming from everywhere, and you get these massive die-offs,” he says. “Well, that’s an education issue, but it’s also an EPA issue—we’ve got to get that language on the label to make it unlawful to spray while a crop is blooming.”

And Delaplane knows that those kinds of changes won’t be easy.

“Changes like that… They’re very slow, very institutional,” he says. “It’s just not the stuff that a quick fix is made of.”

Get More

UGA Honey Bee Program http://www.ent.uga.edu/bees

Managed Pollinator CAP’s Bee Health website http://www.extension.org/bee_health