Night of the Living ZomBees

By R. Gary Raham:

I’m old enough to remember the original Alien movie. An arthropod-style alien attacks crew member, Dallas, by latching onto his face. Dallas seems like a goner for sure until the alien releases its grip and dies (I think). Dallas recovers, seemingly no worse for the wear. But wait. While eating a meal, Dallas gets sick and falls dead onto the table. An alien creature then pops out of his chest and scurries away.

Yuck. But I remember thinking at the time (being a biologist), Wow, that’s a lot like what wasps do to caterpillars. Mother wasps lay their eggs on the larvae of an unsuspecting moth and the wasp larvae eat their prey from the inside and eventually emerge as a young wasps.

Mother Nature can be cruel playing the survival game. Turns out she can also be devious. A variety of parasites from arthropods to fungi to worms and viruses can not only parasitize other creatures but zombify them as well. They change the behavior of their host to maximize the chances for their own progeny.

One example is a bee parasite called Apocephalus borealis, who can turn both native bees and now honeybees into ZomBees. A. borealis used to just attack native yellow jacket wasps and bumblebees. At some point in the early 2000s it adapted to attack honeybees—as if they didn’t have enough problems already.

Honeybees didn’t exist in North America until 1622 when they were imported by European farmers. A California entomologist named John Hafernik, professor of biology at San Francisco State University, first made the discovery when he was searching for bugs to feed some praying mantises he was using in his research.

To find bugs, Havernik searched near outdoor lights at night. At one lamppost he discovered honeybees wandering around in circles. He captured some in a vial and left them unattended for several days in his lab. When he remembered and recovered the vial it contained dead honeybees and the small brown pupae of A. borealis, a type of phorid fly.

A. borealis laying eggs in a honeybee

Phorid flies are wee beasties smaller than fruit flies—not to mention quick. A. borealis can insert her ovipositor into the abdomen of her host and lay eggs within 2-4 seconds. The young larvae that hatch from her labors can munch on a bee’s muscles and perhaps nervous system. Seven days later they are ready to perform their own alien-style exit from the host and form pupae. Nearly a month later adult flies emerge from the pupae to complete the parasite’s life cycle.

While larvae are interacting with the bee’s nervous system, however, behavior of the host also changes. Honeybees leave their hives at night and search for a light source. Once there the bees act like drunken sailors, stretching their legs out, wandering around and falling over. They officially become ZomBees!

Bee on the lookout!

Citizen Scientists are now on the lookout for ZomBees. You can join the crew, if so inclined. The website is www.zombeewatch.org. The map they provide shows that Colorado is either not currently infected or people are still collecting data. It’s easy to sign up to be a bee watcher. They provide a tutorial about the equipment you need, how to handle still living ZomBees, and the kinds of things to record and photograph. Another great resource, especially if you are a beekeeper, is coloradobeekeepers.org.

Are ZomBees the cause of Colony Collapse Disorder (CCD)? They certainly don’t improve a honeybee’s health and welfare, but at the moment it seems that this parasite is only one of many contributing factors to CCD. Scientists are also still ignorant about the precise mechanisms this tiny fly uses to zombify her hosts. A. borealis may somehow interfere with circadian rhythms or light sensitivity.

If the whole idea of zombies and mind control activates your fascination meter, Mindy Weisberger has written a great book called Rise of the Zombie Bugs. Depending on your tolerance for yuck and living dead story lines, you might want to read the stories in daylight with an empty stomach. But if biology is your thing, as it is mine, I think you will find it an entertaining and informative read.

A critical issue with this new threat to honeybees is that this parasite’s assault could soon spread around the globe because hives are transplanted easily and often for commercial purposes. Please be aware of, and perhaps take the more active step of becoming a citizen scientist, if you can. The welfare of our friendly pollinator the honeybee is tied intimately to our own comfort and survival.

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Gary Raham is a biologist who writes both science fact and science fiction. HIs book, Not Quite Dead Geniuses at Large on an Angry Planet, is a 2024 Colorado Book Award Finalist.