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Wildlife & Habitat Protection 3/10/2009 4:32:07 PM EST Some reasonable evidence exists that honeybee colony collapse disorder is the result of malnutrition Partner, Ropers Majeski Kohn & Bentley
Prior posts have noted the phenomenon of honeybee colony collapse disorder (CCD) and the various theories that have been proposed to explain it, including moving the bees around too much (aka stresses), pesticides, genetically modified crops, mites, fungus, and a recently introduced virus (from the Middle East to Australia to the U.S.). It is now increasingly being recognized that managed bees need food supplements. In some places, a decline in the area of pasture land on which bees can forage, the loss of weedy borders, and the growth of monocultures mean it is hard for bees to find a wide enough range of pollen sources to obtain all their essential amino acids. [For an article noting many of the vitamins in honey, and that they vary enormously with each colony, see http://jn.nutrition.org/cgi/content/abstract/23/6/581.]
In extreme cases they may not even find enough basic protein. The working hypothesis is that poor nutrition has weakened the bees' immune systems, making them more vulnerable to viruses and other parasites. Feeding bees supplements, rather than relying on their ability to forage in the wild, costs time and money; many beekeepers therefore try to avoid it. Anecdotal evidence, however, suggests that those who do pay for and feed their colonies appropriate supplements find that their colonies are far more resistant to CCD. See http://www.beeculture.com/storycms/index.cfm?cat=Story&recordID=628.
To date, there has been a dearth of studies that colonies of wild bees are collapsing any more frequently than they used to; this would appear to support the thesis that the problem for commercial colonies is one of nutrition. Although it is true that many species of butterflies, moths, birds, bats, and other wild pollinators are in retreat, their problems are far more likely to mirror broader declines in biodiversity that be the result of well-known phenomena such as habitat loss and the intensification of agriculture. As such, those who try to draw an analogy between these species and commercial bee populations have not made their case. Create an account or login to post comments.
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