Animal Blog

Animal Blog

Zom-bees Take Flight

If you were looking for more evidence of apocalyptic doom in the early days of 2012, listen for a buzzing noise.

San Francisco biologists published findings Jan. 3 revealing that more than three quarters of honey bee hives sampled in the San Francisco Bay area tested positive for a deadly parasite; the fateful Apocephalus borealis fly was also detected in commercial hives near Bakersfield and as far away as South Dakota.

The parasite, a small fly, embeds its eggs into a bee's abdomen. Then a week after the infected bees die, larvae hatch and emerge from their bellies, adding to the self-propagating zombie-like dimension of this narrative.

Infected bees, which media reports have dubbed "zom-bees," become extremely disoriented. They abandon their hives—often at night although bees aren't normally noctural—and flutter toward lights, where they remain stranded until they die. Researchers first found infected, stranded worker bees within light fixtures on the campus of San Francisco State University.

Infected bees also lost their equilibrium, and became unable to stand on their legs or began walking in circles, according to the study, published in the scientific journal PLoS ONE.

Researchers say it's probable that the parasitic flies have long been present at low levels in hives, but speculate that "something has happened recently that has increased density making [the flies] an emerging threat."

The study could provide a key piece of the puzzle in explaining Colony Collapse Disorder, which has decimated some hives across the country, with beekeepers reporting losses of 30 to 90 percent over the past five years. There's no recognizable cause to the disorder, but scientists have been scrambling to find an explanation—and a solution—since honeybees add an estimated $15 billion in value to agricultural products, particularly almonds, berries and fruit. The U.S. Department of Agriculture reports one in three mouthfuls of food are dependent on honey bee pollination.

There are some 2.5 million managed honey bee colonies in the country today, about half as many as there were in the 1940s.

Next steps for researchers will mean identifying how widespread the parasite is, as well as exactly how and where it's happening before there's a recommended solution. "We don't know the best way to stop parasitization, because one of the big things we're missing is where the flies are parasitizing the bees," lead researcher John Hafernik Hafernik, a San Francisco State biology professor, said in a statement. "We assume it's while the bees are out foraging, because we don't see the flies hanging around the bee hives. But it's still a bit of a black hole in terms of where it's actually happening."

Photo by Mark Blevis, courtesy of Flickr.