fly laying eggs inside a honey bee

Get involved in citizen science… help the honeybees!

While researchers have been making progress in discovering causes of Colony Collapse Disorder (CCD), we still don’t have all the answers.
Some of you may remember awhile back when I wrote about a fly called Apocephalus borealis. This fly was discovered by San Francisco State University researchers to be parasitizing honeybees.

There are a lot of questions that need to be answered before we can even think about associating the fly with CCD, and the authors of the original paper are now looking to get the public involved to help answer a lot of these questions.
I had some quibbles with the paper because I think it’s a bit of a stretch to connect the parasite to colony collapse disorder. However, there are many hypothetical ways that this parasitoid could make disease problems worse. If the fly knocks out the immune system, parasitized bees could amplify pathogens more efficiently. The fly could also move pathogens between colonies.
A lot of follow-up research needs to be done, and I think a lot of really basic questions need to be answered before it’s justified to look in that direction. Questions such as:

  • How often do honeybees leave their hives at night? Is this something only sick bees do?
  • Where does this parasitoid occur in the United States, and how widespread is parasitism in honeybees? Are there different biotypes which target honeybees specifically, or are honeybees accidental hosts? Are there widespread correlations between fly activity and colony collapse?
  • Given the geographic range, how often are pathogens implicated in CCD associated with the fly? Can they reproduce in the fly? Can they be spread by the fly somehow? Can the fly make the bees more susceptible to infection?

We currently don’t know the answers to any of these questions. Heck… there’s a lot of things we don’t know about the basic biology of the parasitoid. Or the biology of honeybees. Despite my reservations over the CCD link, I think the original Core et. al paper that I previously wrote about was a good step in the right direction, and the researchers who did the original research are starting to answer these questions.
To answer these questions, the researchers need to find honeybees infected with the flies, which can be problematic. It takes a lot of money to send researchers all over the US, and even then the sample size would be very limited due to time constraints. This is why it’s such a good idea to involve the public in this type of work as a citizen science project. You can simply cover more ground and get data more easily.

fly laying eggs inside a honey bee
A Zombie Fly laying eggs inside a Honey Bee. Image from ZomBee watch.

I really encourage anybody reading Biofortified to get involved in this research. This is a wonderful project. They have set up a website that offers some very detailed instructions on how to collect honeybees and parasitoid flies, including a tutorial on How to Become a ZomBee Hunter. Plus, who doesn’t love some zombie related science?
It won’t take much time out of your day… if you’ve got a porch light and a film canister or baby food jar, that’s all the equipment you need. Just look for honeybees that come to the light at night, save them, and send them to the researchers.
There’s a lot of good information on the website. The researchers pointed a few things out in their FAQ that I’d like to reiterate…

CCD probably is caused by multiple contributing factors including pathogens, parasites and pesticides. Honey bees parasitized by Apocephalus borealis abandon their hive, a behavior associated with CCD. One of our goals is to determine how big a role, if any, the fly plays in hive losses in various parts of North America…
…So far, Apocephalus borealis has not been proven to cause hive failures. Being infected with the fly is clearly not a good thing for honey bees, but at this point we don’t know how large an effect the fly has on hive health.

Happy hunting!


  1. My understanding is this is a native species to North America. Is it found elsewhere? If not, Id agree with you that it is unlikely to be the CCD cause.

  2. Well, the question of whether this fly could be involved is really complicated. This is a species native to North America, and as far as I know it’s not found in Europe or Asia. There are some other parasitoids that attack honeybees in these regions.
    If this fly isn’t present in all regions of the US, that doesn’t neccessarily mean it couldn’t have an indirect role in the regions where it’s present. Phorids will screw up foraging patterns of their eusocial hosts, which could prevent the hive from getting essential nutrition. Poor nutrition, higher disease susceptability.
    On the converse if these guys immunosuppress their hosts, it’s possible that parasitized bees could act as amplifying hosts for other pathogens. It’s also possible that they could spread certian infections through phoresy or their feces even if the pathogens cannot reproduce inside the fly.
    There are a number of ways this fly *could* hypothetically be involved in screwing up honeybee colony populations that are both microbial or ecological. Even though it *could* be involved, that doesn’t neccessarily mean that it *is* involved. My first thought when reading about this paper is not ‘oh, this is a major player’ but rather ‘how does this parasitoid fit in with the ecology of our economically important honeybee hives?’.
    I recently amended the article I wrote on this topic awhile back. I’ve explained more there.

  3. While the neonicotinoids are a strong suspect in CCD, even the papers in the SciAm article are not decisive links. There are other strong elements being investigated and there is a good chance that CCD is a multivariate cause.

  4. Mlema,
    Welcome to the Biofortified comments section. One of the things we really like to see is folks reading multiple articles, and asking questions about them. This means that people are interested and care about what we write. So, thanks for showing up. 🙂
    One of the things that’s really difficult about science is that there are no easy answers…and we love easy answers. The connection between neonics and CCD isn’t nearly as simple as Neonics->CCD. In areas where neonics aren’t used, there are still issues with CCD.
    We’ve done a poor job researching honeybees in the past, and we’re still discovering new honeybee pathogens in 2012. For cattle, we know about how much weight they’ll gain down to the microgram (according to a dairy science person I know) for every milligram of diet they consume. For honeybees, we don’t even know what pathogens constitute the equivalent of a cold or ebola.
    Leaving the colony is a somewhat common symptom of sick honeybees, and there are a bunch of honeybee diseases and parasites that interact in really complicated ways. Nutrition can change the bee’s ability to fight off diseases, and I know of one paper which claims that pesticides can also immunocompromise bees (but I haven’t read it, so I can’t vouch for it).
    One really good post is this one from Bug Girl’s Blog. She’s another entomologist, and she discussed this issue awhile back. The Xerces society is a group dedicated to invertebrate conservation and they put out a paper addressing this issue specifically.
    I should really do a CCD post, shouldn’t I?

  5. yes, but Bug Girl’s blog did a great job.
    personal opinion: I don’t think we need to ignore the evidence on neonicotinoids just because we know that the causes of CCD are multivariant, right?
    although “idiopathic brood disease syndrome” is, I’m sure, an important contribution, it’s just further characterization that needs more research. It seems like there are some positive steps we can take on what we already know (as suggested by bug girl)
    Hope the citizen scientist project can help.

  6. Nobody is saying to ignore evidence, but right now, there are too many confounders to make clear, informed decisions. Neonicotinoids are important protection chemicals because of their low toxicity to many other nontarget species. Replacing them with other chemistry may cause further, unanticipated issues with other species.
    With a multivariate cause, we may yet find a key component that can be addressed to stop or mitigate CCD. We may not need to stop using the entire class, we may need to avoid certain materials for certain uses. The key is to do the research to understand what is going on at an adequate level before we move on.

  7. I was thinking about labeling non-agricultural applications and reducing concentration in those products. (refer to Bug Girl’s blog) Or even eliminating them altogether. It wouldn’t affect our food supply and it could reduce toxicity for honeybees. Is this unreasonable?

  8. From Xerces Society: “Products approved for homeowners to use in gardens, lawns, and on ornamental trees have manufacturer-recommended application rates up to 120 times higher than rates approved for agricultural crops.
    Many neonicotinoid pesticides that are sold to homeowners for use on lawns and gardens do not have any mention of the risks of these products to bees, and the label guidance for products used in agriculture is not always clear or consistent.
    Neonicotinoids can persist in soil for months or years after a single application. Measurable amounts of residues were found in woody plants up to six years after application.”

  9. Mlena,
    There are a lot more things to take into account here. While the rates of neonic application in urban environments are higher it’s not known if this means that the bees are exposed to these environments as much as agricultural environments. Most large apiaries, the beekeepers that pollinate crops, are located in rural areas. If urban gardeners are slathering their gardens with insecticides, that won’t mean much if the bees from the large commercial apiaries never get into those gardens.
    In ornamental plants the Xerces paper clearly states that we do not know how much of the neonics makes it into the parts of the plant, the pollen and nectar, that the bees fed upon.
    One of the graphs that Bug Girl copied from the paper is almost entirely blank, and more or less states that we do not know how many neonics affect the bees.
    I read the Xerces paper soon after it came out and at virtually every possible opportunity, the Xerces paper says that we do not have a full understanding of how neonicotinoids affect bee biology. The paper also says that we don’t have a full understanding of how often their use results in negative effects on bees. Thus, it is too early to say that neonics are the sole cause of CCD as you originally indicated.
    Nobody has said that neonicotinoids are good for bees, or that we should ignore any potential effects. Instead, as Bug Guy pointed out, there are a lot of other things that we need to take into account. There’s a lot of diseases that cause bees to abandon their colonies, and these are often highly correlated with colony collapse. There are also some serious deficiencies in our understanding of honeybee nutrition that need to be addressed.
    Claiming that neonics are the sole cause of CCD with our paltry understanding of the data isn’t helping anybody. Instead, it’s just inventing a quick-fix solution that ignores an infinite number of equally likely culprits. They certainly need to be studied, but so does the role of diet, stress and disease. In reality, diet, stress, disease and pesticides all probably interact to cause the problem.

  10. In fact, the Xerces white paper even comes out and says exactly what The Bug Guy and myself were saying on Page 13 when discussing the topic of Neonicotinoids and CCD. They say it several times in several different ways, which I’ve quoted below.
    I would very strongly recommend reading the entire study as opposed to merely quoting parts of it. It’s definitely shocking how little we know about the subject, but at the same time there’s no way we can honestly know how involved with CCD neonicotinoids are.

    The failure of foraging bees to return to their hives has led many people to suggest that a link exists between CCD and the behavioral disruptions observed with sublethal exposure to neonicotinoid insecticides. As of yet, no single insecticide or combination of insecticides have been linked to CCD, though many chemicals have been found in hives. Researchers that compared gene expression in honey bees from healthy colonies and from collapsed colonies found no link between expression of genes that code for proteins associated with the detoxification of insecticides and collapsed colonies (Johnson et al. 2009). This suggests that insecticide exposure, whether to neonicotinoids or another class, is not a primary factor in CCD.

    While neonicotinoids and other agrochemicals do not appear to be the direct cause of CCD, they may be a contributing factor to already stressed colonies. It is increasingly important that future studies focus on interactions of multiple factors suspected of contributing to CCD.

  11. As others have mentioned, the probable exposure of honeybees to these non-agricultural uses is probably low, with the possible exception of hobbyist beekeepers, whom, I understand, have not been as affected by CCD as commercial beekeepers. I agree that some of the application rates could be lowered. Overkill is not needed.
    I operate a household hazardous waste program and anecdotally, I see few neonicotinoids in comparison to other classes of insecticides. This may be an indication that these products are not used as much as things like organophosphates and synthetic pyrethroids, which I see far more often.

  12. I support everything you’re saying and it’s very important to get to the bottom of this. I’m just the sort of person who looks to do what can be done when it can be done. I hope I will be able to help. It would certainly be time better spent than I often spend it now 🙂

  13. Actually, I’m sort of hoping I don’t find any zombees – although I’m not sure whether that would be a good indicator of a lesser problem or not. (thanks)

  14. Mlema,
    I have tried to participate in this study, and the problem is that I don’t encounter a whole lot of bees where I’m at. Some of my friends who live on the outskirts of town have given me bees (n=6 so far) they find at lights, and I’ve dissected them. I’ve yet to find a single phorid fly maggot, which leads me to believe that they’re not common around here. I could be wrong on this…6 bees is a miniscule sample.
    There are a few sources of information I’d like to steer you towards. The first is a website called Extension, and this site is basically an amalgam of articles written by extension entomologists across the country:
    The other thing I’d like to direct you towards are the annual reports put out by the USDA annually which serve as an update for the research that’s going on in this area:
    This is the most recent report as far as I know, and it summarizes the important research published in the year 2011. It gives a good overview on what we know about the roles of pesticides, pathogens and nutrition on honeybee health. Unfortunately, we’re still very much in the dark and will be for awhile. I think the next one comes out this summer.

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