Sunday, January 8, 2012

The Parasitic Honey bee Fly

Parasitic fly penetrating the body of a honey bee. 
     Apocephalus borealis, a parasitic fly was recently discovered by John Hafernik, a biology professor at San Francisco State University to parasitize the bodies of honey bees.  This fly was previously known to parasitize bumble bees and paper wasps but not honey bees.  To this point it is a localized phenomena as it has only been found in the San Francisco area (77% of sites tested) and commercial hives in California's Central Valley and South Dakota.  
     This phorid fly lays eggs in the bee's abdomen and several days later the affected bee leaves the hive disoriented, often at night and may fly towards a light source.  Within a short period of time the bee dies and as many as 13 fly larvae crawl out of the bee's neck.  The parasite affects mostly foraging bees and may be a carrier of several diseases like deformed wing virus and Nosema ceranae (found in parasitized bees).  The nocturnal abandonment behavior of the affected bees may be a behavior manipulation by the parasite similar to that found in parasitized fire ants and gypsy moths.  The host behavior manipulation may be an adaptive evolutionary strategy for the benefit of the parasitic larvae.  The possible desire being for the larvae to leave the bee's body in safety away from the hive.  It may also be that the affected bee leaves the hive, knowing it is affected and dying, to save the hive.  The selfless, altruistic behavior of bees in defense of their hive has been well documented.  
     As stated before this phenomena is very localized and should be treated as such (no immediate cause for alarm).  Of the hives studied in the San Francisco area only 5-15% of the hive was affected.  Not enough to decimate the hive as the varroa mite will do.  Of greater concern may be the viruses carried by the parasitic fly.  Hopefully, Apocephalus borealis is not as mobile as the varroa mite.  The immediate concern would be for the massive California agricultural industry. Affected hives mean reduced pollination which means diminished agricultural production.

Parasitic larvae leaving the neck of a dead honey bee. 
     I believe the problems of the honey bee today (Colony Collapse Disorder) are directly related to the problems of our environment.  The two cannot be separated. You cannot have a healthy bee population and an unhealthy earth.  Recently a single grain of pollen taken from an agricultural area of France was found to contain more than 50 different types of pesticides, fungicides and herbicides. Scientists have discovered that these toxins, along with industrial and household toxins remain in our environment for many years (much longer than they thought). The accumulation factor has dire consequences for the honey bee's relatively weak immune system.  The honey bee has one third the number of genes involved in it's immune system than that of a fruit fly.  As such it is a good indicator species (canary in the coal mine) for the health of our environment.  The weakening effects of these environmental toxins amplifies the effects of otherwise manageable pathogens and pests.  The answer, simple, a clean earth and hygienically bred bees. 
     This news video describes the effects of the parasitic honey bee fly.    


     Please visit and sign the petition to the United Nations to ban the use of neonicotinoid pesticides which are toxic to bees (


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