Like the undead in a horror movie, zombie bees are known for their distinctive lurch. The honeybees were first discovered in California in 2008, and now have been spotted in Washington state.

Zombie bees are regular bees infected with a parasitic fly that changes its host’s behavior and eventually leads to death. The parasitic fly attacks the bee by using a sharp appendage to pierce the bee and lay an egg inside it. When the egg hatches, the maggot feeds on the bee’s organs. Infected bees are likely to fly after dark, unlike normal bees, which return to their hives when the sun sets. The zombie bees are also drawn to lights, and as the infection progresses, they begin to fly erratically and eventually lurch on the ground.

Earlier this month, a beekeeper discovered that the zombie bees had spread to Washington. The beekeeper collected samples of the insects, and is one of many citizen scientists sharing data with, a website run by San Francisco State University biologist John Hafernik. Hafernik hopes to discover more about how the parasite is spreading, and determine if it is contributing to the collapse of bee colonies.

Bee populations have been dropping rapidly since 2006. Researchers have various theories about the causes of Colony Collapse Disorder, including cell phone use and pesticides. The problem is particularly serious because of honeybees’ important role in pollinating crops. Bee pollination is responsible for more than $15 billion in crop value. The parasitic fly is likely worsening colony collapse, though it’s not yet clear if it has a major impact.

In the San Francisco Bay Area, nearly 80 percent of hives are infected with the parasite. Infected bees have also been found in other parts of California, Oregon, and now, in Washington. Anyone who discovers a suspicious bee is encouraged to report it to ZomBeeWatch.

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