the bee apocalypse

bee-vanish

Since 2006 honey bees responsible for pollinating more than 100 crops—from apples to zucchini—have been dying by the tens of millions, as reported by the US Department of Agriculture (USDA).  Scientists have been struggling to understand the causes of so-called Colony Collapse Disorder (CCD) leading so many bees to death (an estimated 10 million beehives, worth $2 billion, have been estimated to have died over the past six years). Recently, a new study has outlined some of the probable causes of bee die-off. Suspects have included pesticides, disease-bearing parasites and poor nutrition. Scientists at the University of Maryland and the USDA have identified a mixture of pesticides and fungicides contaminating pollen that bees collect to feed their hives. The findings break new ground on why large numbers of bees are dying though they do not identify the specific cause of CCD, where an entire beehive dies at once. The results of the research have been very recently published on the Journal PlosOne.

Pettis JS, Lichtenberg EM, Andree M, Stitzinger J, Rose R, et al. (2013) Crop Pollination Exposes Honey Bees to Pesticides Which Alters Their Susceptibility to the Gut Pathogen Nosema ceranae. PLoS ONE 8(7): e70182. doi:10.1371/journal.pone.0070182

Recent declines in honey bee populations and increasing demand for insect-pollinated crops raise concerns about pollinator shortages. Pesticide exposure and pathogens may interact to have strong negative effects on managed honey bee colonies. Such findings are of great concern given the large numbers and high levels of pesticides found in honey bee colonies. Thus it is crucial to determine how field-relevant combinations and loads of pesticides affect bee health. We collected pollen from bee hives in seven major crops to determine 1) what types of pesticides bees are exposed to when rented for pollination of various crops and 2) how field-relevant pesticide blends affect bees’ susceptibility to the gut parasite Nosema ceranae. Our samples represent pollen collected by foragers for use by the colony, and do not necessarily indicate foragers’ roles as pollinators. In blueberry, cranberry, cucumber, pumpkin and watermelon bees collected pollen almost exclusively from weeds and wildflowers during our sampling. Thus more attention must be paid to how honey bees are exposed to pesticides outside of the field in which they are placed. We detected 35 different pesticides in the sampled pollen, and found high fungicide loads. The insecticides esfenvalerate and phosmet were at a concentration higher than their median lethal dose in at least one pollen sample. While fungicides are typically seen as fairly safe for honey bees, we found an increased probability of Nosema infection in bees that consumed pollen with a higher fungicide load. Our results highlight a need for research on sub-lethal effects of fungicides and other chemicals that bees placed in an agricultural setting are exposed to.

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5 thoughts on “the bee apocalypse

  1. Dr. Thomas E. Ferrari MS, PhD says:

    It is often erroneously reported that “Since 2006 honey bees responsible for pollinating more than 100 crops—from apples to zucchini—have been dying by the tens of millions.” Actually, the sudden loss and disappearance of honey bees from a hive or apiary has been plaguing beekeepers for more than a century. This age-old disorder predates virtually all herbicides, pesticides, many diseases, pests and honey bee management protocols. “Evaporation,” “Disappearance Disease,” “Dwindling Disease,” “Autumn Collapse,” May Disease” and “Colony Collapse Disorder” (CCD) are names used throughout history to describe the same observation: an unexpected, abrupt and severe loss of adult honey bees from a colony and apiary. The phenomenon has been re-discovered and re-documented periodically around the world for more than a hundred years.

    • Dear Thomas,

      Thanks for your comment. As you say, correctly, the phenomenon has been known for centuries with different names (e.g. disappearing disease, spring dwindle, May disease, autumn collapse, and fall dwindle disease) and described and reported in science papers as well as popular articles. It is also true that the same phenomenon seems to be way more serious now (in the last decade or so) than what it used to be in the past, especially if we consider its geographical extent and the contemporaneity of the phenomenon itself in areas quite apart from each other (North America & Europe as an instance). Now, the potential causes of the CCD (or whatever we want to call it) are several as recently reported by the European Food Safety Authority in its last review (EFSA Journal, 2013, 11(1):3066), with the single causes difficult to identify and a synergistic effect of all the causes with a potential detrimental impact to be the most likely cause of concern (as always…). Interesting, the last published paper puts some more light onto the problem and tries to give a more comprehensive view of the issue (that’s my personal opinion, indeed). Finally, to comment on the main point of your message (… honey bees have always died, and the current mortality should not me a big surprise… – i apologize if my paraphrase is incorrect) my thought is, you’re probably right but is always better to keep an eye or two on what is going on; probably the great concern arises from the fact that the tremendous die-off is worth billions of dollars which are getting lost by the corporations.

  2. More than honey – a recent documentary by Markus Imhof, who’s grandpa was a bis big style beekeeper. Astonishing images and revealing stories from around the world, from t million $ US industrial beekeeping to chinese pollinators where bees are gone completely to swiss mountain beekeepers, Watching the film I stumbled upon an former university collegue who now studies the “last healthy bee colonies” in a Noah ark like situation on remote australian islands. What comes after the die offs is also looked at….
    Sylvan

    • Thanks Sylvan for your comments. Apologies for late replay but was flying around the Med for field work. Still traveling at the moment with limited internet access. I’ll watch the videos ad soon ad I can. But from your description they sound interesting already.

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