Researchers confirm first 'zombie bee' discovery in Canada

Vancouver Island finding adds to mounting evidence that phenomenon is prevalent coast to coast

SAN FRANCISCO, Aug. 15, 2016 — "Zombie bees" have crossed the border, as researchers at San Francisco State University have confirmed the first discovery of parasitized honey bees in Canada. The finding, made on Vancouver Island, was announced this week by ZomBee Watch, a project based at the University.

SF State Professor of Biology John Hafernik and his colleagues first reported parasitized honey bees in 2012 in an article in the journal PLOS ONE. After being infected with a fly parasite, the bees abandon their hives to congregate at night near lights, dying after a bout of disoriented, "zombie-like" behavior. Hafernik and other researchers are tracking the phenomenon with the help of almost 3,000 citizen scientists who report possible parasitized bee sightings to ZomBee Watch.

Early "zombee" sightings were mostly limited to the U.S. West Coast and South Dakota, but the latest discovery adds to the mounting evidence that the phenomenon is widespread across North America. Parasitized bees were found for the first time in New England in 2013, followed by the mid-Atlantic region and upstate New York in 2014 and 2015, respectively. Earlier this summer, researchers confirmed the first zombie bee discovery in the southern United States, in Virginia.

"The important next steps are to determine how common the phenomenon is in Canadian honey bees, whether it might be spreading and increasing in intensity and how serious it is for the health of honey bee colonies," Hafernik said.

In order to do that, Hafernik is urging more individuals to join the zombee hunt to help researchers collect more data regarding the spread of zombie bees. He and his team have developed a series of videos to help new hunters get started, and Hafernik says now is the ideal time to get involved.

"We expect that infection rates will rise during the summer and peak in the fall," he said. "We are already receiving reports of honey bees being hard hit this year in the Hudson Valley of New York, and of course we got confirmation earlier this summer that zombie bees are present in the U.S. South. More than ever, we need citizen scientists to join the ZomBee Watch team, to be on the lookout for honey bees acting strangely in their area and report their observations."

The Canadian bees were discovered by Vancouver Island beekeeper Sarah Wallbank in July, after just three months as a new beekeeper. She knew something was up when she started noticing some of her bees flying toward – and even into – a light.

"My hive is quite close to my house, and there would be a handful of bees that would ping their little brains out against the glass," said Wallbank, who lives in Nanaimo, British Columbia. "I thought, 'This is not normal.'"

A Google search led Wallbank to the ZomBee Watch project, and she collected her samples and uploaded photos of them to the ZomBee Watch website. Brian Brown, a phorid fly expert at the Natural History Museum of Los Angeles County confirmed that they had been infected by the Apocephalis borealis fly, the parasite behind the zombee infestations. The fly infects a honey bee by depositing its eggs into the bee's abdomen. A few days after the bee dies, fly larvae burst out from between the bee's head and thorax.

Beekeepers who find their hives are infected should stay calm and use the best beekeeping practices to keep their hives as healthy as possible, as it is most likely that healthy hives are better able to survive infections from the phorid fly or any other pathogen, according to Hafernik.

"The success of ZomBee Watch demonstrates the power of citizen scientists to make significant contributions to answering important scientific questions,"  Haferniik said. He and his colleagues from the SF State Department of Biology, the SF State Center for Computing for Life Sciences and the Natural History Museum of Los Angeles County launched in 2012 to encourage citizen scientists to report cases of parasitized bees, which were first discovered on the SF State campus. Since then, more than 200,000 people have visited the project's website and more than 2,800 zombee hunters have submitted some 886 samples to be tested for infestation. Roughly 25 percent of participants are beekeepers, and the rest are interested citizens doing their part to help track this new threat to honey bees.


San Francisco State University makes things happen. Founded in 1899, it is the only master's-level public university serving the counties of San Francisco, San Mateo and Marin. Its nationally acclaimed programs span a broad range of disciplines. Nearly 30,000 students enroll at the University each year, and its more than 236,000 graduates have contributed to the economic, cultural and civic fabric of San Francisco and beyond. Through them -- and more than 1,600 world-class faculty members -- SF State proudly embraces its legacy of academic excellence, community engagement and commitment to social justice. For more information, visit