mystery illness linked to bee losses may be stress

There is a buzz among the nation's beekeepers, but it's not the result of the annual spring awakening of their bee colonies.

Beekeepers in 22 states have reported the collapse of large numbers of honey bee colonies as warmer temperatures prompt the beekeepers to examine over-wintered colonies for the first time in spring.  In some cases no adult bees were found in the colony, and few if any dead bees had built up in front of the colony.  Colony collapses were first reported in 2006, and already reports are rolling in for the 2007 season.

University of Tennessee Extension cautions against panic, however.  We do not know if Colony Collapse Disorder is present in Tennessee at this time. Some beekeepers have discovered losses higher than normal, while others have lost only a few colonies from definable causes.

Some experts are even questioning the existence of the disorder.  There is much confusion about this disorder because no causative agent has yet been discovered.  It's been labeled a "mystery killer" and the "AIDS" of beekeeping, but this statement only stirs emotions without justification."

Honey bees play an important economic role in agriculture.  Nationally, the insects serve as pollinators of numerous crops valued in excess of $14 billion annually. In Tennessee, Skinner says the value is more like $67 million. Crops include fruits and vegetables - practically everything from apples to blackberries, pumpkin, squash, cucumbers and beans.  Commercial beekeepers offer pollination services by transporting their colonies to contracting farms.

Many growers and even home gardeners have realized that by adding colonies of

honey bees during bloom of their crop, they can increase yields substantially. CCD was first reported by a migratory beekeeper who annually moves 3,000 colonies of bees from Florida up the east coast to pollinate oranges, apples, blueberries, cherries and pumpkins.  An average colony can include as few as 6,000 individuals in the winter, but populations swell to more than 50,000 in the summer months.  In October, 2006, the beekeeper discovered he had inexplicably lost two thirds of his bee colonies.

About the same time, beekeepers from other states started to report unusually large colony losses, too.  Up to and exceeding 50 percent of their colonies were gone.

Researchers and regulatory agencies are looking for a causative agent or for a combination of agents.  Possibilities including bacteria, fungi, protozoa, viruses and other cumulative stresses. While you can't discount the possibility of a new disease, we may just have an over-stressed bee population.

In some cases of collapsed or collapsing colonies, the presence of tracheal and Varroa mites has been verified.  If you add stresses due to frequent moving, fluctuating temperatures, and the presence of chemical contaminants that may have accumulated over time in the wax comb, then the picture is not clear. Multiple stresses can cause colony mortality.

Earlier this year a group of scientists and apiculturists formed a working group to study CCD. They agreed on symptoms for the disorder and together with Bee Alert Technology, Inc (BATI), the group is asking beekeepers to report suspected instances of CCD.  Beekeepers wishing to participate in the survey, should visit the Web site: www.beesurvey.com                   

Tennessee beekeepers should watch their colonies' activities and monitor for Varroa mites using ether/sugar rolls or sticky board traps.  "They should also be feeding colonies that lack sufficient honey stores.

Tennessee keepers wishing to monitor for microscopic tracheal mites should take a sample of quick-killed bees (60+), placed in 70% rubbing alcohol (enough to cover), and sealed in leak-proof, unbreakable container to the local county UT Extension office. The sample will then be sent to the bee laboratory at the University of Tennessee. The cost per sample is $15.  Please call (865) 974-7138 before sending the sample.

Beekeeping in Tennessee (Extension publication 1745) is available on the Web at http://utextension.tennessee.edu/publications/pests/default.asp#beekeeping.  Interested parties may download it for free or purchase a printed copy for $10.