The bees in the above video aren't dead, but they're about as zombified as bees could be. They're suffering from just one of the many ailments putting honey bee colonies under pressure: a devastating parasite.

When the parasitic fly Apocephalus borealis crosses paths with certain species of bee — increasingly, the european honey bee — it aggressively pursues the bees and lays its eggs inside them. You probably don't need me to tell you that having another species grow and hatch inside you is no good. As the larvae grow, they feed off of the muscle and nervous system of their host bee, eventually destroying the brain. After a few weeks, they bust their way out of the bee's body by making a split between the head and the thorax. 

Besides being eaten from the inside out by fly larvae, the zombees will exhibit unusual behavior: They'll wander around in circles, leave their hives to fly around at night, and get disoriented by following bright lights. 

The attack of the zombie flies seems to be spreading. Honey bees were first recognized as targets in California back in 2008, and beekeepers in New England spotted zombified bees as well in 2014. Just weeks ago, there was a report of a parasitized bee in New York for the first time.

Keep bees? Then you can help keep an eye out. Join ZomBee Watch, a Web site that lets beekeepers and nature lovers help scientists track the problem.

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