Possible Causes of Colony Collapse Disorder (CCD)

A colony which has collapsed from CCD is generally characterised by all of the following conditions occurring simultaneously. (i) The presence of capped brood in abandoned colonies. Bees normally will not abandon a hive until the capped brood have all hatched, (ii) The presence of food stores, both honey and bee pollen, which are not immediately robbed by other bees and which when attacked by hive pests such as wax moth and small hive beetle, the attack is noticeably delayed, (iii) The presence of the queen bee. If the queen is not present, the hive died because it was queen-less, which is not considered CCD.

Precursor symptoms that may arise before the final colony collapse are (i) Insufficient workforce to maintain the brood that is present, (ii) The workforce seems to be made up of young adult bees, and (iii) The colony members are reluctant to consume provided feed, such as sugar syrup and protein supplement.

The mechanisms of CCD are still unknown, but many causes have been proposed as causative agents: malnutrition, pathogens, immunodeficiencies, mites, fungus, pesticides, beekeeping practices (such as the use of antibiotics, or long-distance transportation of beehives) and electromagnetic radiation. Whether any single factor or a combination of factors (acting independently in different areas affected by CCD, or acting in tandem) is responsible is still unknown.

Click on the links below to get more information about the potential effects of pesticides, pathogens, electromagnetic radiation and migratory bee-keeping on colony collapse disorder.
    In March 2013, two studies were published showing that neonicotinoids affect bee long term and short term memory, suggesting a cause of action resulting in failure to return to the hive. Growth in the use of neonicotinoid pesticides has roughly tracked rising bee deaths.

    In 2013, researchers collected pollen from hives on the east coast and fed it to healthy bees. The pollen had an average of nine different pesticides and fungicides. Further, the researchers discovered that bees that ate pollen with fungicides were three times more likely to be infected by parasites. Their study shows that fungicides, thought harmless to bees, may actually play a significant role in CCD. Their research also showed that spraying practices may need to be reviewed because the bees sampled by the authors foraged not from crops, but almost exclusively from weeds and wildflowers, suggesting that bees are more widely exposed to pesticides than thought.

    In April 2013, the European Union voted for a two-year restriction on neonicotinoid insecticides. The ban will restrict the use of imidacloprid, clothianidin, and thiamethoxam for use on crops that are attractive to bees. Eight nations voted against the motion, including the British government which argued that the science was incomplete.

    In March 2013, professional beekeepers and environmentalists jointly filed a lawsuit against the United States Environmental Protection agency for continuing to allow the use of neonicotinoids in the United States. The suit specifically asks for suspension of clothianidin and thiamethoxam. The lawsuit follows a dramatic die off of bees in the United States, with some beekeepers losing fifty percent of their hives. The EPA responded to the suit by issuing a report blaming the Varroa mite for the decline in bees and claiming that the role of neonicotinoids in bee extinction has been overstated. Meanwhile Congress is considering the Save America's Pollinators Act of 2013 (H.R. 2692). The proposed act, spearheaded by Representatives John Conyers (D, MI) and Earl Blumenauer (D, OR), and co-sponsored by Rep. Lucille Roybal-Allard (D, CA) and Rep. Carol Shea-Porter (D, NH), asks that neonicotinoids be suspended until a full review of their impacts has occurred. The Save America's Pollinators Act was drafted immediately following the largest documented die off of bees in the United States which took place in the parking lot of a department store in June 2013. The neonicotinoid Safari, which had been sprayed on linden trees, was suspected of killing the bees.
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    Varroa Mite

    According to research done in 2007 at the Pennsylvania State University: "The magnitude of detected infectious agents in the adult bees suggests some type of immunosuppression". These researchers initially suggested a connection between Varroa destructor mite infestation and CCD, suggesting that a combination of these bee mites, deformed wing virus (which the mites transmit) and bacteria work together to suppress immunity and may be one cause of CCD.

    According to a 2007 article, the mite Varroa destructor remains the world's most destructive honey bee killer, due in part to the viruses it carries including deformed wing virus and acute bee paralysis virus, which have both been implicated in CCD. Affliction with Varroa mites also tends to weaken the immune system of the bees. Dr. Enesto Guzman, an entomological researcher at the University of Guelph in Canada, studied 413 Ontario bee colonies in 2007–08. About 27% of hives did not survive the winter, and the Varroa mite was identified as the cause in 85% of the cases. As such, Varroa mites have been considered as a possible cause of CCD, though not all dying colonies contain these mites.

    Nosema Disease

    Some have suggested that the syndrome may be an inability by beekeepers to correctly identify known diseases such as European foulbrood or the microsporidian fungus Nosema. The testing and diagnosis of samples from affected colonies (already performed) makes this highly unlikely, as the symptoms are fairly well known and differ from what is classified as CCD. A high rate of Nosema infection was reported in samples of bees from Pennsylvania, but this pattern was not reported from samples elsewhere.
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    In 2004, an exploratory study was conducted by investigators at the University of Landau on the non-thermal effects of radio frequency ("RF") on honey bees (Apis mellifera carnica). The investigators did not find any change in behaviour due to RF exposure from DECT cordless phone base stations embedded in them, operating at 1880–1900 MHz [reference]. In 2006, these same investigators extended this study and this time suggested that the close-range electromagnetic field ("EMF") may reduce the ability of bees to return to their hive; they also noticed a slight reduction in honeycomb weight in treated colonies. In the course of their study, one half of their colonies broke down, including some of their controls which did not have DECT base stations embedded in them. In April 2007, news of this study appeared in various media outlets, beginning with an article in The Independent, which stated that the subject of the study included mobile phones and had related them to CCD [reference]. Though cellular phones were implicated by other media reports at the time, they were not covered in the study. Researchers involved have since stated that their research did not include findings on cell phones, or their relationship to CCD, and indicated that the Independent article had misinterpreted their results and created "a horror story" [reference].

    In October 2011, a review study was published by the Indian government's Ministry of Environment and Forests that looked at 919 peer-reviewed scientific studies investigating impacts of EMF on birds, bees, humans, animals/wildlife, and plants [reference]. Only 7 of the 919 studies involved honey bees, and 6 of these claimed negative effects from exposure to EMF radiation, but none specifically demonstrated any link to CCD. The review noted that according to one study [reference], when active mobile phones were kept inside beehives, worker bees stopped coming to the hives after ten days. The same study also found drastic decrease in the egg production of queen bees in these colonies and goes on to claim that "electromagnetic radiation exposure provides a better explanation for Colony Collapse Disorder (CCD) than other theories". In view of evidence from this and several other studies, the review authors concluded: "existing literature shows that the EMRs are interfering with the biological systems in more ways than one" and recommended recognising EMF as a pollutant. However, they also noted that "these studies are not representative of the real life situations or natural levels of EMF exposure". They concluded that more studies need to be taken up to scientifically establish the link, if any, between the observed abnormalities and disorders in bee hives such as Colony Collapse Disorder (CCD).

    The video below is present by Starling W. Childs, M.S., geologist and forestry consultant, and adjunct faculty member at the Yale School of Forestry and Environmental Studies. He claims that it’s clear to him that bees, which operate within the natural background field of electromagnetic energy that the earth produces, locate their food sources by following a natural lay line are being confused and completely cross modulated by electromagnetic frequencies made by us for our technological advance. Is he correct? Is more research required on this subject? You decide.

    Commonwealth Club 11-18-10. Panel I - Starling W. Childs, M.S. from ElectromagneticHealth.Org on Vimeo.

    Environmental effects of electromagnetic radiation (EMF)
    Migratory Bee Keeping
    Since U.S. beekeeper Nephi Miller first began moving his hives to different areas of the country for the winter of 1908, migratory beekeeping has become widespread in America.

    Bee rental for pollination is a crucial element of U.S. agriculture, which could not produce anywhere near its current levels with native pollinators alone. U.S. beekeepers collectively earn much more from renting their bees out for pollination than they do from honey production.

    Researchers are concerned that trucking colonies around the country to pollinate crops, where they intermingle with other bees from all over, helps spread viruses and mites among colonies. Additionally, such continuous movement and re-settlement is considered by some a strain and disruption for the entire hive, possibly rendering it less resistant to all sorts of systemic disorder.