What’s Killing the Honeybee?

It’s a serial murder case with vanishing dead bodies and several suspects. It may sound like the premise of a movie, but it’s actually colony collapse disorder (CCD), a phenomenon in which honeybees mysteriously disappear from their hives, leaving behind the queen and their young.

CCD first appeared in the United States in 2006, when a commercial beekeeper noticed that 60 percent of his colonies disappeared in the span of a couple months. When the media picked up the story, more reports came in: bustling hives of bees reduced to nothing in a matter of weeks. Today, about a third of all hives in the U.S. have vanished. Typically when diseases or mites kill bees, bodies litter the hive and the surrounding area. In the case of CCD, the bees simply disappear.

The disorder has also afflicted hives in France, Italy, Spain, and other European countries. The cause is unknown. A combination of factors is most likely causing CCD, said Ramesh Sagili, assistant professor of apiculture, or beekeeping, at Oregon State University: “Six years of research: we haven’t found a single pathogen or a pest that is responsible for this.”

According to Sagili, modern bees have more stressful lives than their ancestors due to commercial farming methods. This combined with a poor diet may make them susceptible to mites, viruses, and pesticides.

“There is no one cause,” said Sagili. “We think all these factors together are compromising the immune system.”


Food sources such as the 80 million acres of monoculture corn that blanket the U.S. make for a bland diet. Most commercial beekeepers bring their bees to California during the almond pollination season, and stay there for a month and a half. During that time, the 1.5 million hives of bees eat only almond pollen. The results are the same as if a person ate only chicken for a month and a half.
“The immune system gets compromised,” said Sagili.

Pesticides and Fungicides

Bees who get into crops treated with pesticides and fungicides store these chemicals in the hive where larvae and adults feed on them. This, too, can compromise a bee’s immune system, leaving it more susceptible to diseases or pests.

France has banned neonicotinoids, a class of insecticides linked to bee deaths. Currently, the U.S. is the biggest user of neonicotinoids–and the country where CCD is most prevalent. However, “I don’t think any one class of insecticide could kill bees in those numbers,” noted Sagili.

Physiological Stress

Commercial beekeepers maintain a migratory pattern, trucking their bees from Maine to Florida, Texas, and California, following a seasonal pattern. The journey itself, plus the changes in weather and temperature, stresses the bees and confuses their biological clocks.

Lack of Genetic Diversity

Honeybees are not native to North America. They were brought over from Europe in the 1600s and imported until 1922, when the Honeybee Act closed U.S. borders to bees from other countries in an effort to block diseases and pests. This law limited the genetic diversity of our bees. Each year, breeders buy their queens from a limited supply.

“Only a handful of breeders produce the queens used in the United States,” said Sagili.

Mites, Parasites, and Viruses

A mite that feeds on the blood of bees transmits several viral diseases. Hives that are not treated for mites have a good chance of being wiped out. Other parasites live in the bees’ stomachs and may make them unable to digest the protein they eat. Hungry and weak, the bees go out in search of more food.
“They go out foraging and they don’t have the energy to come back,” said Sagili, who noted that losing a thousand bees a day due to this could cause CCD in a month or two.

Life without the Honeybee

Without bees, there would be no almonds. Honeybees pollinate almost 100 different food crops. Luckily, bee colonies regenerate fairly quickly.
“Beekeepers have the ability to make up for the loss,” said Sagili. “Replacing hives is easy compared to other livestock. That’s why we haven’t felt the pinch.”

Over the next five years, the U.S. Department of Agriculture is spending $20 million on research into CCD. If we lose the bee, the potential losses are enormous: $15 billion in crops each year, and about a third of the food on our plates.

How to Help the Honeybee

Planting lavender, basil, roses, phacelia, or sunflowers in your yard helps provide bees with a balanced diet that’ll give their immune systems a boost. Or you could become a backyard beekeeper–and gain honey in return.

By Jen Matteis